Public health Flashcards
Implied consent
Exposing part of the body
(assumptions)
* Blood pressure
* Examination
verbal consent
- Intimate examinations (all
examinations?) - Examination for teaching purposes
- Low risk procedures (local agreement)
- Record in the notes
when is written consent used
- Higher risk procedures
- Local requirements
- Legal requirements
- Research
- Emergencies
- Recording information
- Duration of written consent
Special circumstances with consent
- Mental capacity
– Assessment; involving others - Age
- Advanced care planning
Definition of public health
Developed as a discipline in the mid 19th century in UK, Europe and US.
Concerned more with national issues.
Data and evidence to support action, focus on populations, social justice and equity, emphasis on preventions vs cure.
What is international health?
Developed during past decades, came to be more concerned with
the diseases (e.g. tropical diseases) and
conditions (war, natural disasters) of middle and low income countries.
Tended to denote a one way flow of ‘good ideas’.
What is global health?
More recent in its origin and emphasises a greater scope of health problems and solutions
that transcend national boundaries
requiring greater inter-disciplinary approach
Why do people start smoking?
Usually in teenage years- psychosocial motives
Influence of background- smokers around them, deprived areas ect
Why do people keep smoking?
Nicotine addiction
Habit/cues
Social, economic, personal, and political influences all play an important part in determining patterns of smoking prevalence and cessation
Physical and psychological effects of smoking
Nicotine has pervasive effects on brain chem
Activates nicotinic acetylcholine receptors in the brain and causes dopamine release in the NAcc
Stimulant
Tolerance and withdrawal
Describe the relationship between smoking and social inequality
Smoking has been identified as the single biggest cause of inequality in death rates between rich and poor in the UK
Smoking prevalence among unemployed adults was 35% compared with 19% of adults who were in employment in 2011 (General Lifestyle Survey 2011)
What is the impact of smoking?
Greatest single cause of illness and premature death in the UK
About 100,000 people in the UK die each year due to smoking.
Deaths mainly due to cancer, COPD and heart disease
1/2 of all smokers die from related diseases
What is the economic impact of smoking?
Costs NHS around £2.4bn
Smokers spend around 3.4k per year on cigarettes
Loss of productivity and absenteeism costs £13.17bn and 1.3bn respectively
Describe the 1951 British doctors study
A questionnaire on smoking habits was sent to all British doctors included in the medical register and survivors have been contacted at regular intervals since 1957.
The 40-year study (1994) showed that 80 per cent of non-smokers survived to age 70 and 33 per cent to age 85 whereas only 50 per cent of heavy smokers survived to age 70 and 8 per cent to age 85.
“It now seems that about half of all regular cigarette smokers will eventually be killed by their habit.”
Other smoking studies
American Cancer Society Nine State Study- Concluded that 22% of ischemic heart disease in men and 19% in women was attributed to smoking.
The Canadian Veterans Study-Found those who had ever smoked were 25 times as likely to die from lung cancer than those who had never smoked.
The American Cancer Society Twenty Five State Study-It showed that smokers of cigarettes had a death rate of 9.2 times the rate for those who had never smoked.
Describe some other health problems that can be influenced by smoking
-Cardiovascular problems
-Other cancers
-Stomach ulcer
-Impotence
-Diabetes
-Oral health -Cataracts
Describe smoking cessation practices
Once a person knows they want to stop they can enrol onto a smoking cessation programme
This means receiving support to stop smoking (e.g. NHS Stop Smoking Services)
If they get such support they can also access nicotine replacement therapy (NRT), other medication, or an e-cigarette
What support do stop smoking services provide?
The NHS Stop Smoking Service uses a combination of support, advice, cognitive and behavioural strategies and pharmacological aids (NRT, bupropion, varenicline)
One-to-one or group, online and telephone support
The Stop Smoking Service works on the principle that it is only possible to help people to quit who want to quit
Technically this is the “Stages of change theory/ Transtheoretical Model”
If someone is motivated to stop smoking the Ready, Steady, Stop plan can help
Describe the ready steady stop method
Ready - be prepared and aware, understand the process
Steady - set a quit date, throw away your lighter and ashtrays
Stop - set a plan for the day, avoid triggers, reward yourself
What are some pharmacological interventions?
Nicotine replacement therapy (NRT): available on prescription if you are part of an NHS scheme or available to buy from pharmacies
Patches, gum , nasal spray, microtab, lozenge, inhalator
Non-nicotine pharmacotherapy: bupropion and varenicline, are licensed in the USA and Europe
Varenicline (Champix)
Bupropion (Zyban)
Electronic cigarettes
Describe brief advice that can be given to smokers
Brief advice should be delivered opportunistically during routine consultations – guidelines recommend doing this once a year
1%-3% of patients who receive brief advice (≤5 min) from a GP stop smoking for ≥6 months
Can trigger motivation to quit
What are the 3 A’s of brief advice
Ask – Establish smoking status
Advise – Advise on the most effective way of stopping smoking
Act – Provide options for support and access to medications – e.g. make a referral to the Yorkshire Smokefree Sheffield Service
What is screening?
A process which sorts out apparently well people who probably have a disease (or precursors or susceptibility to a disease) from those who probably do not.
Why?
To make a real difference to health
It is not intended to be diagnostic (diagnostic tests are different).
It is a process, not simply a test
What are the main purposes of screening?
Secondary prevention
and
Primary prevention
What is secondary prevention?
Aim – detect early disease in order to alter the course of the disease
e.g. screening by mammography for breast cancer in order to treat it early
WHat is primary prevention?
Aim - prevent a disease from occurring
screening to identify people with risk factors and reduce risk factor levels
WHy screen?
Reduce the risk of developing disease
Provide treatment
Provide information
E.g. pre-natal screening for genetic disorders
What is sensitivity?
Sensitivity – the proportion of people with the disease who are correctly identified by the screening test
a / a+c
What is specificity?
Specificity – the proportion of people without the disease who are correctly excluded by the screening test
d / b+d
What is PPV?
Positive predictive value – the proportion of people with a positive test result who actually have the disease
a / a+b
What is NPV?
Negative predictive value – the proportion of people with a negative test result who do not have the disease
d / c+d
Why is the positive predictive value so different between high and low prevalence?
Predictive values are dependent on underlying prevalence
(Sensitivity and specificity are not)
What are the Wilson and Junger criteria for the condition?
The condition
The condition sought should be an important health problem
The natural history of the condition should be well understood
There should be a detectable early stage
What does the treatment have to be like to fit the criteria for screening?
There should be an accepted treatment for patients with recognized disease.
Facilities for diagnosis and treatment should be available
Adequate health service provision should be made for the extra clinical workload resulting from screening
What does the test have to be to fit the criteria for screening?
A suitable test should be devised for the early stage
The test should be acceptable
Intervals for repeating the test should be determined (not a one off)
What do the risks and benefits have to be to fit the criteria for screening?
Risks and benefits
There should be an agreed policy on whom to treat
The costs should be balanced against the benefits
Additionally
The risks, both physical and psychological, should be less than the benefits
How should we evaluate screening?
Ideally by RCT
individual
cluster
Could use other methods but potential for bias
Well recognised biases
Selection bias
Lead-time bias
Length-time (or length) bias
What is selection bias?
People who choose to participate in screening programmes may be different from those who do not
May be at higher risk
e.g. women with family history of breast cancer more likely to attend
May be at lower risk
e.g. women in higher socioeconomic groups (lower risk of cervical cancer) more likely to attend
What is lead time bias?
What is length time bias?
What are the types of screening?
Population-based screening programmes (“mass” screening)
-Thailand, national diabetes and hypertension screening
Opportunistic screening
-Prevention and control of substance abuse
Screening for communicable diseases
-Heaf test?
Pre-employment and occupational medicals
-Vision test for commercial drivers?
Commercially provided screening
-Screening is more than a test, it is a
programme
What is the social definition of disability?
It is the loss or limitation of opportunities to take
part in society on an equal level with others due to
social and environmental barriers.
* A disabled person is a person with an impairment
who experiences disability.
* Disability is the result of negative interactions that
take place between a person with an impairment
and her or his social environment.
* Impairment is thus part of a negative interaction,
but it is not the cause of, nor does it justify,
disability.
What are some disability barriers?
- negative cultural representations;
- inflexible organisational policies, procedures
and practices; - segregated social provision;
- inaccessible information formats;
- inaccessible built environment and product
design.
Describe the negative cultural representations of disabled people
Images and assumptions that medicalise, patronise,
criminalize, and dehumanise people with impairments.
How do inflexible organisational policies,
procedures and practices affect people with disabilities?
- Many deaf people or those with a hearing impairment were
forced to make contact with their GP using a method that was
not the best for them - 90% of GP surgeries in Wales did not offer suitable
alternatives for making appointments.
What is the definition of a learning disability?
- Significant impairment of general cognitive
functioning acquired in childhood that is lifelong. - Leads to difficulty with everyday activities, e.g.
household tasks, socialising or managing money. - People with a learning disability tend to take longer
to learn and may need support to develop new skills,
understand complicated information and interact
with other people.
Describe the epidemiology of learning disabilities
About 4% of population- in 2011 1.2 million ppl in the UK
2.5% of children
Boys more likely than girls
More common in poorer/ less educated households
What are some factors that affect the presence of a learning disability?
-genetic factors
– maternal use of alcohol, drugs and tobacco during
pregnancy
– complications during pregnancy
– and environmental toxins, such as cadmium and lead
What are the differences between the prevalence of physical disorders in disabled and non-disabled people?
Higher prevalence of many disorders such as CHD, respiratory disease, visual impairment, msk impairments and constipation
Lower prevalence of death from cancer
Outline down syndrome
One of the commonest causes of LD
* ~ 40,000 persons with DS in England and Wales (prevalence of
~6 per 10,000)
* More than two thirds are adults.
Average life expectancy for babies with DS born in 2011 was
now 51 years (median of 58 years).
What does having down syndrome increase the risk of?
– dementia,
– thyroid problems,
– visual/hearing impairment
– and other associated long term medical conditions.
What are some social factors of having a learning disability?
- more likely to be economically disadvantaged
– Less than 7% in some form of employment in 2010/11 - have communication, numeracy , literacy and memory
difficulties - have personal health risks and behaviours;
- experience deficiencies in access to and the quality of
healthcare provision. - have increased risk associated with specific genetic and
biological causes of learning disabilities
What are some barriers for disabled people accessing healthcare?
-Failure to provide adjustments
-Discriminatory attitudes
-Failure to provide accessible info
-Diagnostic overshadowing
-Can’t make appointments alone
-Problems with reading appt letters or info leaflets
-Might not trust doctors bc of past trauma
What are some health promotion issues for people with learning disabilities
- Low uptake of health promotion or screening activities among
- Access to health promotion considerably poorer for people
with more severe LD
Describe the annual health check scheme for people with LD
Adults with LD should have annual health checks but the offer
and uptake is poor.
* Health checks are effective in identifying previously
unrecognised health needs, including life threatening conditions
* UK studies report that 88% of persons with LD had specific
health needs identified through a health screening process.
* Annual health checks in primary care for these adults may not
alter overall emergency admissions, but may reduce
preventable emergency admissions by ~18%
Health consequences of mistreatment of people with LD
Premature mortality- due to a failure to diagnose and treat illnesses
Inappropriate use of DNAR orders
Poorer mental health- over prescription of antibiotics
What do we need to do to be good doctors for ppl with learning disabilities?
– Registration with a GP is important in accessing screening
programmes
– Primary care mandated in GP contract to offer people
with learning disabilities an annual holistic health check.
– Easy read formats for patient information leaflets
– Patient champions
– Be aware and mindful of their needs!
WHat is the difference between health inequalities and inequities?
Why is environmental health important?
Individual and population health influenced by
Housing
Sanitation
Food safety
Water quality
Environment quality
Often the poorest groups are most exposed and vulnerable to environmental hazards
What are some traditional environmental health problems?
Water, sanitation and drainage
Garbage collection and waste disposal
Housing structure
e.. ventilation, infestations
Air pollution
Nutrition
House sites
hazards e.g. accidents, floods, illegal occupation
Health services
access
What are some of the vectors of disease?
Breeding of vectors of disease e.g.
Mosquitoes
Transmit diseases such as malaria, dengue fever, Japanese Encephalitis B, yellow fever, Chikunguya
Flies
Transmit foodborne disease such as Typhoid fever, dysentery and cholera
Rats
What is risk transition?
Move from traditional hazards to modern hazards
What are traditional hazards?
Related to poverty & insufficient development:
- Lack of safe drinking water,
Inadequate sanitation,
Indoor air pollution,
Inadequate waste disposal
What are modern hazards?
Related to development that lacks health & environmental safeguards, & to unsustainable consumption of natural resources:
- Environmental contamination
Urban air pollution
Climate change
Describe water pollution
Microbiologically contaminated drinking water can transmit diseases such as diarrhoea, cholera, dysentery, typhoid, hepatitis A, and polio
Causes ~505,000 diarrhoeal deaths each year.
Also risks from chemical pollutants in drinking water e.g. arsenic
What is cryptosporidium?
Intracellular parasite
Commonest non-viral cause of diarrhoea worldwide
Prevalence ~ 1% - 4.5% of population in North America/Europe. (3% - 20% in developing countries)
80% of the population has had cryptosporidiosis.
Peak age of incidence 1-5 years, marked reduction over 35 years.
Describe transmission and the risk groups
Faeco-oral transmission
Person-to-person spread
Nurseries
Food handlers
Animal contact
MSM
risk groups for cryptosporidium
Occupational risk groups
Vets
Animal handlers
Farm workers
Waterborne transmission of cryptosporidium
Transmitted in surface run-off water contaminated by calf faeces.
Incidence seasonal and related to rainfall.
Manure fertilizers
Waterborne
Oocysts are resistant to standard chlorination or many disinfectants.
Unboiled tap water
Swimming pools
What is the clinical manifestation of cryptosporidium?
Self-limiting in most healthy individuals
Low infectious dose
Symptoms: watery diarrhoea lasting 2-4 days, abdominal cramps, fever, vomiting, anorexia.
Likelihood of recurrence in cases (auto-infection).
Can lead to malnutrition from malabsorption, gall bladder infection
Can get chronic cryptosporidiosis in patients who are immunodeficient (e.g. AIDS)
Difficult to treat.
Describe prevention of cryptosporidium
In general, good hygiene & handwashing is essential, especially after handling animals.
Avoid ingesting water if swimming in lakes, rivers or swimming pools.
You should not swim in a swimming pool for 14 days after your symptoms have cleared. This is because cryptosporidium can still be present in your stools during this time.
Food handlers should stay away from work until 48 hours after the last episode of diarrhoea or vomiting.
Water companies routinely test for it
Drink only treated water
Immunocompromised persons should drink boiled water.
Describe sources of arsenic in the water
naturally present at high levels in the groundwater of a number of countries, e.g. Argentina, Bangladesh, Cambodia, Chile, China, India, Mexico, Pakistan, USA.
industrial processes: e.g. as an alloying agent, processing of glass, pigments, textiles, paper, metal adhesives, wood preservatives, hide tanning, pesticides, and pharmaceuticals.
tobacco
What can long-term exposure to arsenic cause
Long-term exposure to arsenic can cause
Skin lesions
Cancers of the bladder, lungs and skin,
Arsenic-induced myocardial infarction
Diabetes
Adverse outcomes in pregnancy
Also affects cognitive development
Describe lead poisoning
Exposure to lead can affect multiple body systems and is distributed to the brain, liver, kidney and bones.
No level of exposure to lead that is known to be without harmful effects.
Young children are very vulnerable and can suffer profound and permanent adverse health impacts, particularly on brain and central nervous system, and can lead to acute encephalopathy, coma, convulsions and even death.
Causes long-term harm in adults, including increased risk of high blood pressure, cardiovascular problems and kidney damage.
Exposure of pregnant women can cause miscarriage, stillbirth, premature birth and low birth weight.
How do people get lead poisoning?
People can become exposed to lead through occupational and environmental sources:
inhaling lead particles generated by burning materials containing lead (e.g. during smelting, recycling, stripping leaded paint and plastic cables containing lead) and leaded fuel
ingesting lead-contaminated dust, water (from leaded pipes) and food (from lead containers) and from hand-to-mouth behaviour (e.g. pica) due to lead paint.
What is used to manage, treat and prevent lead poisoning?
Key management action is to removing the source of exposure!
Some patients may require chelation therapy
Prevention: phasing out of lead-containing fuel, lead in paint
What are some health concerns about slum areas?
Diseases like hypertension, diabetes, intentional and unintentional injuries, tuberculosis, rheumatic heart disease, leptospirosis and HIV infection exist in slums
Late complications of these diseases seen
Issues of poverty and disadvantage, that affect access to healthcare and good health
Also limited access to key services e.g. clean water, sanitation etc…
What are some concerns with food hygiene and safety?
Almost 1 in 10 people in the world fall ill after eating contaminated food and 420,000 die every year.
Foodborne illnesses usually infectious or toxic in nature and caused by ingestion of food contaminated with bacteria, viruses, parasites or chemical substances.
Food hygiene refers to the practices used to minimize the risks of foodborne illnesses caused by bacterial contamination.
Involves proper food handling, transport, storage, processing/preparation of food
What is autonomy?
Emmanuel Kant’s Categorical
Imperative, that you should treat others
as ends in themselves and not merely
as a means to an end.
* Subsumes informed consent before
treatment, confidentiality, honesty (lack
of deceit) and good communication
What is beneficence?
Doing the right thing for patients
* A Subset of respect for autonomy in
many ways
* Also incorporates empowerment;
helping the patient to make appropriate
decisions for themselves
What is non-maleficence?
Not doing the wrong thing to patients
* Not harming patients intentionally or
inadvertently where ever possible.
* Means evidence based practice
* And keeping up to date
* Again, it is a subset of respect for
autonomy
What is justice?
The moral obligation to act on the
basis of fair adjudication between
competing claims
* Distributive justice - Fair distribution of
scarce resources
* Rights based justice - Respect for
people’s rights.
* Legal Justice - Respect for the Law
What are some behaviours related to health?
Sleep
Smoking
Eating
Exercise
Ways to categorise health behaviours?
Health damaging/impairing
Health promoting
What are soem damag9ing health behaviours
Smoking, alcohol and substance abuse, risky sexual behaviours, sun exposure, driving without a seatbelt
Health promoting
Exercise, healthy eating, attending health checks, medication compliance, vaccinations
What are some modifiable risk factors?
(things we can potentially change)
Diet/ Excessive weight, Smoking, Alcohol, Physical activity, Sleep, Stress
What are some non-modifiable risk factors?
(things that we cannot change)
Sex, Age, Genetics/ Family history
Why is it important to know about behaviour change?
➢Important from both an individual and population perspective
➢ Overwhelming evidence that changing people’s health behaviour can have
an impact on some of the largest causes of mortality and morbidity
What is population level intervention?
➢Health promotion
*The process of enabling people to exert control over the
determinants of health, thereby improving health
What is individual level intervention?
➢Patient centred approach
*Care responsive to individual needs
Effects of intervention (using the example of alcohol)
*Individual’s behaviour (level of alcohol consumption, individual health
outcomes, or incidence of domestic violence)
*Local community (local alcohol sales, alcohol-related crime or accident and
emergency [A&E] events)
*Population level (for example, national alcohol sales and consumption,
national statistics on alcohol-related crime and A&E events, or demographic
patterns of liver cirrhosis)
What is unrealistic optimism when it comes to risky health behaviours?
Individuals continue to practice health damaging behaviour
due to inaccurate perceptions of risk and susceptibility
What are perceptions of risk influenced by?
- Lack of personal experience with problem
- Belief that preventable by personal action
- Belief that if not happened by now, it’s not likely to
- Belief that problem infrequent
What are some models and theories of behaviour change?
- Health belief model (HBM)
- Theory of Planned Behaviour
- Stages of change (transtheoretical) model
What is the health belief model?
Individuals will change if they:
➢ Believe they are susceptible to the condition in question (e.g. heart disease)
➢ Believe that it has serious consequences
➢ Believe that taking action reduces susceptibility
➢ Believe that the benefits of taking action outweigh the costs
Health belief model applied to breast cancer screening
The HBM predicts that an individual will attend the screening programme if:
They perceive themselves at high risk or susceptible to breast cancer, that
breast cancer is a serious threat to their health/ life, that the benefits of
screening are high, and that the costs of such actions are low.
What is the theory of planned behaviour?
Proposes the best predictor of behaviour is ‘intention’ e.g. I intend to give up
smoking
Intention determined by:
* A persons attitude to the behaviour
* The perceived social pressure to undertake the behaviour, or subjective
norm
* A persons appraisal of their ability to perform the behaviour, or their
perceived behavioural control
What is perceived behavioural control?
Someone’s belief that they can change their behaviours
Theory of planned behaviour applied to smoking cessation
Attitude – I do not think smoking is a
good thing
Subjective Norm – most people who are
important to me want me to give up
smoking
Perceived Behavioural Control – I
believe I have the ability to give up
smoking
Behavioural Intention – I intend to give
up smoking
What is the stage models of health behaviour theory?
Stage theories see individuals located at discrete ordered stages, rather
than on a continuum
Each stage denotes a greater inclination to change behaviour
Transtheoretical model, or Stages of change model
Proposes 5 stages of change: precontemplation, contemplation,
preparation, action, maintenance
Transtheoretical model applied to smoking cessation
Precontemplation – no intention of giving up smoking
Contemplation – beginning to consider giving up, probably at some illdefined time in the future
Preparation – getting ready to quit in the near future
Action – engaged in giving up smoking now
Maintenance – steady non-smoker,
i.e. state of change reached
Routine health data
Regularly collected
Data to describe the population health status, health care and factors influencing it
Why do we collect health data?
- Monitor population health
- Generate hypothesis of causes of ill health
- Inform planning of services and policy
- Evaluate and assess performance
-Generate research statistics
Types of health information collected
- Mortality
- diseases
- Use and quality of health care
- Health status/ quality of life
- Individual lifestyle ( health relates behaviour)
- Wider determinants ( socio-economic, cultural and environmental conditions)
- Population (demographics)
Mortality statistics- how they are recorded and analysed
- Dr completes certificate of cause of death
- Informant takes certificate to local registrar and registers death
- Copy of reg sent to ONS when cause of death are coded
- Causes of death are analysed
WHO cause of death recording
Disease of injury that initiated the train of events leading to the death
The
Quality of data CART
C
A
R
T
How does greenspace provide health and
well-being benefits?
- mitigation of harm
- restoration of depleted capacities
- building new capacities
- microbial diversity
Mitigation of environmental harm on health
- Reduce Air pollution
- Noise reduction
- Temperature regulation
How does natural area restore depleted capacities?
- reduction of stress - Improved relaxation
and restoration - increases in positive emotions
- facilitation of recovery from attentional fatigue
Building new parks
- Community and Social cohesion
- physical exercise
Effect and mechanism of Microbial diversity
3 pillars of public health
Health improvement
Health services
Health protection
science of public health
Epidemiology
The who, what, when and where of disease
Statistics
Making sense of big numbers
Health economics
Ethical rationing
Costs vs benefits
The art of public health
Changing the status quo requires:
Influence
Leadership
Relationships
Authenticity
Partnership working / collaboration
Patient and public engagement
What is intersectionality?
Intersectionality is a concept for understanding how aspects of a person’s identities combine to create different and multiple discrimination and privilege.
What are health inequalities?
Health inequalities are unfair and avoidable differences in health across the population, and between different groups within society. Health inequalities arise because of the conditions in which we are born, grow, live, work and age. These conditions influence our opportunities for good health, and how we think, feel and act, and this shapes our mental health, physical health and wellbeing.”
Health inequality factors
Socioeconomic factors- Education, employment, income, family and social support, community safety- 40%
Physical environment- Housing, access to green spaces, air quality - 10%
Lifestyle factors- Diet and physical activity, tobacco use, alcohol use- 30%
Healthcare- Access to good quality health care services, experience of care and patient satisfaction- 20%
Medical history causes of cardiovascular disease
Male
Family history
Past medical history of CVD
Hypertension
Raised lipids
Smoking
Lifestyle factors that increase risk of CVD?
Smoking
Obesity
Sedentary lifestyle
Physical inactivity
Excess alcohol
Stress
Poor diet
Social causes of the causes of CVD?
Loneliness
Unemployment
Poor housing
Fear of crime
No access to green space
Food poverty
Pollution
Social inequality
Social determinants of health
Non-clinical factors that impact physical and mental health
Some links between social factors and mental health
Poverty- can cause or be caused by mental health problems
Childhood adversity- esp abuse and sexual abuse
Social capital- how ppl can draw on their social networks and value ascribed to them
Education- school a place for social support
Healthy aging
Inequalities- greater inequality is linked with higher mental health
Give an overview of BMI
Body mass index (BMI)– weight divided by the square of height (kg/m2)
Overweight: BMI 25-30
Obese: BMI 30 or higher
Morbid obesity: BMI over 40
Excess weight umbrella term for BMI over 25
BMI is not a perfect measure, not appropriate for all groups and other measures are
used – waist circumference, waist-hip-ratio
Food environment as a driver for ill health
Deprived areas have up to five times as many fast-food outlets – influences food choice
(Brandkvist et al. 2019)
Food restriction limiting availability:
* Foods deserts – areas of poor access to healthy food options, poverty premium
* Food swamps – areas of greater provisions of unhealthy, nutrient poor, caloricdense food and drinks
Commercial determinants of health: negative impact of commercial activities
* Increased exposure to advertisements (Ziaudden et al. 2018, Penney et al. 2018)
* Promotions in supermarkets, portion sizes, front of pack labelling, SSB taxes
People living in deprived areas more likely to experience food insecurity.
Outline food insecurity
What is it?
A major public health challenge
How is food insecurity defined?
Experiencing one or more of the following:
1. Having smaller meals than usual or skipping meals due to being unable to afford
or get access to food.
2. Being hungry but not eating due to being unable to afford or get access to food.
3. Not eating for a whole day due to being unable to afford or get access to food
What is the socio-ecological model of health?
How diverse aspects of the
host, agent and
environment are implicated
in multifactorial aetiology of
disease
Situates all behaviours in
the social context
Prevention is not just about
public health interventions
in the health care system
but about the wider
determinants of health that
can only be changed
through more widespread
social action
Causes of child mortality
Diarrhoeal disease
Acute Respiratory Infections
Malnutrition
Vaccine Preventable Diseases
e.g. Measles, pertussis, etc.
Neonatal causes
Medical causes of maternal mortality
Haemorrhage
Obstructed labour
Puerperal sepsis
Eclampsia
Social causes of maternal mortality
Too young
Too soon … after the last child
Too late … to access healthcare
Too many
Leading causes of death in HICs
- CVR disorders
- Cancer
- Resp disorders
- Nervous system disorders
- Digestive disorders
Leading causes of death in LICs
- Lower resp infections
- HIV/AIDS
- Diarrhoeal diseases
- Stroke
- Ischaemic heart disease
- Malaria
- Preterm birth complications
- TB
Determinants of disease
- Close contact
- Overcrowding
- Smoking
- Indoor air pollution
- Delayed health seeking
- No access to care
Determinants of outcomes
- Ease of access to care
- Affordability of care
- Reliability of care
- Stigma/taboo
- Lack awareness & understanding
- Mental wellbeing
- Gender
- Socio-economic deprivation
- Migrant status
Definition of global health
“health problems, issues, and concerns that transcend national boundaries, may be influenced by circumstances or experiences in other countries, and are best addressed by cooperative actions and solutions.”
Why is global health so important?
Massive disease burden in the world‘s poorest nations poses a huge threat to global wealth and security.
Millions around the world die of preventable and treatable infectious diseases because they lack access to basic medical care and sanitation.
Potential to save millions of lives each year, but only if wealthy nations provide the poorer ones with the requisite services and support.
Why is global health relevant for doctors?
Previously, medical schools had little on global health in their curricula but that is changing
Health is a growing global problem, with chronic diseases being the main killer worldwide
By learning about global health, medical students will be better equipped to face future challenges
Outline changing age distribution in populations
Previously, medical schools had little on global health in their curricula but that is changing
Health is a growing global problem, with chronic diseases being the main killer worldwide
By learning about global health, medical students will be better equipped to face future challenges
Wildcard
have a biscuit!
Poverty and health
1.3 billion people live on less than $1 a day, more than half the world lives on less than $2 a day
20% of the world population have no access to modern health services.
6 billion people have no access to improved sanitation facilities in 2006
In low-income countries, 65% of the population face health risks because of inadequate sanitation
Source: WHO World Health Statistics 2008
Explain the holistic conceptualisation of sexual health
Sexual (& reproductive) health:
* is about well-being, not merely the absence of disease.
* involves respect, safety and freedom from discrimination and violence.
* is relevant throughout the individual’s lifespan, not only to those in the reproductive years.
* is expressed through diverse sexualities and forms of sexual expression.
* is critically influenced by gender norms, roles, expectations and power dynamics
What is included in sexual health?
Sexual (& reproductive) health:
* is about well-being, not merely the absence of disease.
* involves respect, safety and freedom from discrimination and violence.
* is relevant throughout the individual’s lifespan, not only to those in the reproductive years.
* is expressed through diverse sexualities and forms of sexual expression.
* is critically influenced by gender norms, roles, expectations and power dynamics
Why is SRH important?
Estimated to account for 20% of global burden of ill-health among women and 14% among men
Even more significant among the poor; some countries 5/10 leading causes of lost DALYs relate to SRH
Determinants closely linked to socio-cultural, economic and political aspects of society. Increasingly portrayed as a human rights issue
Social and economic impacts huge. Priority public health area in the UK and globally
What place is unsafe sex in the list of causes of burden of disease?
High mortality developing subregion- 3
Low mortality developed subregions- 9
What are SRH trends in the UK driven by?
-Changing patterns of mortality and morbidity
-Technological and medical advances
-Wider socioeconomic and cultural changes in society
-Shifting social norms, values and attitudes
-Inter-play between these elements
What are the SRH trends in the UK?
Rising gap between sexual debut, cohabitation and childbearing
Fall in teenage pregnancy rates
Older age childbearing
Change in significance of HIV/AIDS
Reduction in prejudice based on sexual orientation
Increasing expectations of sexual fulfilment at older ages
Increased treatment for infertility
‘Normal birth’; choice
Visibility of sexual violence and exploitation
Diversifying population; growing inequalities and vulnerable groups
Current UK SRH policy priorities
- Fall in unwanted pregnancies, esp. those resulting in terminations
- More HIV testing in high-risk groups; reduced late stage diagnosis
- Access to free condoms; knowledge to prevent STIs
- Protecting children from sexual abuse and exploitation
- Continue to eradicate prejudice based on sexual orientation
- Build confidence and ability to say ‘no’ as well as ‘yes’
- Build knowledge and resilience in young people
- Women-centred maternity services; social models of care; choice; continuity
- Improve service access; tackle inequalities; vulnerable groups
Some key concerns to do with SRH locally and globally
STIs including HIV/AIDS
Maternal mortality and morbidity
Female genital mutilation
Outline STIs
- Caused by more than 30 different bacteria, viruses and parasites
- Spread predominantly by sexual contact, including vaginal, anal and oral sex
>1 million people acquire STI every day - Majority are asymptomatic
- Some STIs increase risk of HIV infection 3-4x
- Consequences include infertility, mother-to-child transmission and chronic diseases
- Nearly 1 million pregnant women infected with syphilis in 2016 resulting in >200,000 stillbirths and newborn deaths
- Drug resistance, especially for gonorrhoea
Common STI’s
Chlamydia
Gonorrhoea
Syphilis
Trichomonas Vaginalis(TV)
Chancroid
Donovanosis
Herpes Simplex Virus (HSV) - “Cold sore virus”
Human Papilloma Virus (HPV) – “Wart virus”
Hepatitis A, B & C
Human Immunodeficiency Virus (HIV)
What helps drive the STI epidemic?
- Poverty/social deprivation
- Migration
- Rapid urbanisation
- Economic & political instability / war
- Absence of diagnostic and treatment services for STIs
- Early sexual debut
- Multiple partners
- Absence of visible symptoms
- Unprotected sex
- Substance misuse
- Lack of public awareness
- Lack of training of health workers
- Stigma
- Sex tourism
SRH in adolescents in young adults
More likely to have multiple sexual partners (sequential or concurrent) rather than long-term sexual relationships
May have difficulty using barrier methods that would offer protection from STIs
May be more likely to have higher-risk partners
May have less access to STI care because of different factors:
Lack of awareness
Non disclosure of sexual activity
Fear of being found out by parents/carers
Restrictive policies of clinics
Lack of money to pay for care – not an issue in the UK but relevant in other parts of the world where you pay for health care
Absence of symptoms does not mean absence of infection
- Up to 70% of women & 50% of men with Chlamydia have no symptoms
- Helps drive the epidemic
Risk factors of STIs
Several partners
Frequent partner change
Unprotected sex
Consequences of poor sexual health
Serious implications for both individuals and society
poor reproductive and maternal health
STIs are the main preventable cause of infertility especially in women.
Post infection tubal damage responsible for 30-40% of female infertility
10-40% of untreated women with genital Chlamydia develop Pelvic Inflammatory Disease (PID)
40-50% of ectopic pregnancies can be attributed to previous PID
Consequences of poor sexual health on newborns
Could also lead to poor newborn health:
Eye infections in the newborn
Chlamydia, Gonorrhoea
Could lead to blindness
Congenital syphilis
Angiogenital cancers
Some strains of HPV can lead to cancer of the cervix, anus, vulva, penis
How does STIs affect the transmission of HIV?
The presence of untreated STIs increases the risk of acquiring and transmitting HIV by up to 10 times
Outline SRH in England today
Diagnoses of STIs on the increase
Highest among young people, some minority ethnic groups and men who have sex with men
Recent rise also among those >45 yrs.
Sexual ill health disproportionately affects vulnerable groups e.g.
young people
minority ethnic groups
those affected by poverty and social exclusion
Outline the HIV/AIDS as a public health issue
HIV continues to be a major global public health issue, having claimed 36.3 million lives so far.
There is no cure for HIV infection.
Increasing access to effective HIV prevention, diagnosis, treatment and care, including for opportunistic infections, has made HIV infection a manageable chronic health condition
~37.7 million people living with HIV at the end of 2020, over 2/3 of whom are in the WHO African Region.
In 2020, 680,000 people died from HIV-related causes and 1.5 million people acquired HIV.
Key messages of HIV prevention
Individuals can reduce the risk of HIV infection by limiting exposure to risk factors.
Key approaches for HIV prevention, which are often used in combination, include:
male and female condom use
testing and counselling for HIV and STIs
testing and counselling for linkages to tuberculosis (TB) care
voluntary medical male circumcision (VMMC)
use of antiretroviral drugs (ARVs) for prevention
harm reduction for people who inject and use drugs
elimination of mother-to-child transmission (MTCT) of HIV
treatment as prevention
But only 73% of people living with HIV were receiving ART in 2021!
Outline chlamydia
Most commonly diagnosed STI in the UK
Prevalence of infection is highest in young sexually active women (15 to 24 year olds), and is approximately twice the prevalence in 16 to 44 year olds (3.1% compared to 1.5% in women)
May have long-term implications including infertility.
Of those women with untreated chlamydia 10 to 17% will develop PID. 35% of PID in women aged 16 to 24 attributable to chlamydia
National chlamydia screening programme, targeting especially young women under 25 yrs
What is involved in primary prevention of STIs?
Goal is to inhibit the development of disease before it occurs
- Counselling and behavioural interventions
- Interventions targeted at key populations
- Immunisation e.g. Hepatitis A & B, HPV
Outline STI interventions targeted at key populations
E.g., comprehensive sex education, safer sex/risk-reduction counselling, condom promotion - when used correctly & consistently, condoms are one of the most effective methods of protection against STIs
Counselling can improve people’s ability to recognize symptoms of STIs and increase likelihood they will seek care or encourage a sexual partner to do so
Immunisation as a way to prevent STIs
In UK, initially only in girls aged 12-18. Now also in men who have sex with men
Secondary prevention of STIs
Goal is to identify and detect disease in its earliest stages, before noticeable
STI screening
HIV testing – e.g. universal testing at GU clinics, antenatal clinics, etc
Especially useful for the diagnosis of asymptomatic infections
Hinges heavily on accurate diagnostic tests which may not be readily available in resource poor settings
Rapid/point of care tests very useful
A good way of achieving this is by integrating STI services into existing health services e.g. reproductive health services
Tertiary prevention of STIs
Involves actual treatment of the disease
Prompt & effective treatment is given
To cure the disease
To prevent and limit complications/sequelae
To prevent transmission
Single dose regimens if possible to aid treatment compliance
Prevent re-infection: abstinence till completion of treatment, identification and treatment of contacts
Surveillance of STI
Surveillance is an integral part of any STI control program
To obtain information on the burden of STIs in the population
To determine the demographic and geographical distribution of STIs and trends
Outline GUM clinics
Confidentiality & non-judgemental attitude to encourage attendance
Open access
Accurate diagnosis & effective treatment (preferably on the day of presentation)
Screen for concomitant infections – often asymptomatic
Free treatment – single dose & oral preferred
Contact tracing
Outline cervical cancer
Cervical cancer is the 4th most common cancer among women globally
~604 000 new cases and 342 000 deaths in 2020.
~90% of new cases and deaths worldwide in 2020 occurred in LMICs
Two HPV types (16 & 18) responsible for nearly 50% of high grade cervical pre-cancers
HPV mainly transmitted through sexual contact
Most people are infected with HPV shortly after the onset of sexual activity.
Women with HIV 6 times more likely to develop cervical cancer than women without HIV
HPV vaccination and screening and treatment is cost-effective to prevent cervical cancer.
Cervical cancer can be cured if diagnosed at an early stage and treated promptly.
Comprehensive cervical cancer control includes
primary prevention (vaccination against HPV),
secondary prevention (screening and treatment of pre-cancerous lesions),
tertiary prevention (diagnosis and treatment of invasive cervical cancer)
Outline maternal health
99% of all maternal deaths occur in developing countries
Lifetime risk of dying as a result of pregnancy or childbirth 1 in 6 in the poorest parts of the world vs 1 in 30,000 in Northern Europe
Common causes:
Post-partum bleeding
Unsafe abortion
Pregnancy-induced hypertension
Postpartum infection
Obstructed labour
Can lead to long-term morbidities and disabilities
Significant inequalities in maternal mortality and morbidity in the UK
UK inequalities in maternal health
Confidential Enquiries into maternal deaths (CEMACH/CMACE)
5x higher risk of maternal death in Black African compared to White women
Likelihood of severe maternal morbidity significantly associated with non-White ethnicity
Black African and Black Caribbean highest risk (Linquist et al. 2013; Knight et al. 2008)
Also, poorer birth outcomes (prematurity, low birth weight, infant mortality) and lower satisfaction among minority ethnic groups
Sub-standard care contributes to these inequalities
Outline the need for contraception
Family planning allows people to have desired no. of children and to determine the spacing of their pregnancies.
Prevention of unintended pregnancies lowers maternal ill health and pregnancy-related deaths.
Health benefits of delaying pregnancies in young girls who are at increased risk of health problems from early childbearing, and among older women who also face increased risks.
By reducing unintended pregnancies, also reduces need for unsafe abortion. Also benefits education, employment, etc
In 2017, 214 million women of reproductive age in developing regions have an unmet need for contraception due to
limited access to contraception
limited choice of methods
a fear or experience of side-effects
cultural or religious opposition
poor quality of available services
gender-based barriers.
Outline female genital mutilation
Sometimes referred to as female circumcision
Procedures that intentionally alter or cause injury to the female genital organs for non-medical reasons
Some communities believe it is a necessary custom to ensure that a girl is accepted within the community and eligible for marriage
Perceived health benefits, preservation of the girl’s virginity, cleanliness, rite of passage, status in the community, protection of family honour, perceived religious justifications.
It is illegal to perform or arrange for FGM to be carried out on a girl in the UK or to take a girl abroad (FGM Act 2003; Serious Crime Act 2015)
Has a negative impact on a person’s dignity, physical, psychosocial and moral integrity and development, participation, health, education and economic and social status.
What are the signs that girls could be at risk of GFM?
- Mother has undergone FGM
- Mother has requested re-infibulation following childbirth
- Has older sibling or cousin who has undergone FGM
- Parents/elder relatives consider FGM integral to cultural/religious identity
- Girl/family has limited level of integration within UK community
- Girl withdrawn from PSHE/SRE
- Girl makes references to FGM in conversation, or confides she is to have a “special procedure” or attend a special occasion to “become a woman”
- Parents state the child will be taken out of country for a prolonged period and are evasive about why
- Girl is to be taken out to a country with high prevalence of FGM (especially during the summer holidays which is known as the cutting season)
Global prevalence of FGM
At least 200 million girls and women alive today living in 30 countries have undergone FGM (UNICEF)
Africa (almost universal in Somalia, Guinea, Djibouti)
Middle East (e.g. Iraq, Yemen, Oman, UAE, Saudi Arabia)
Asia (e.g. Indonesia, Malaysia, India)
UK
areas with communities of first generation immigrants, refugees and asylum seekers: London, Cardiff, Manchester, Sheffield, Northampton, Birmingham, Crawley, Reading, Milton Keynes, Slough, Oxford
Key challenges to SRH intervention
Deep seated hierarchies and inequalities difficult to address; e.g. gender and poverty
Closely linked to religious and moral understandings: - opposition from churches and other religious leaders - personal views of healthcare providers, teachers etc. powerful - policy decisions influenced by public opinion
Stigma, discrimination, confidentiality concerns, compounded by legality issues
Wide range of providers; disjointed: general practice, community services, acute hospitals, pharmacies and the voluntary, charitable and independent sector, schools
Data gaps and inadequate evidence on what works for different groups and in different settings
What factors go into food consumption regulation?
- Homeostatic mechanisms to protect against excessive food deprivation
- Gene-environment interaction
- Habitual, social, stress/ emotional eating behaviours – “passive” overconsumption
- Hedonic mechanisms (pleasure and reward)
Direct controls of meal size
All factors relating to the direct contact of food to the gastrointestinal mucosal
receptors.
Indirect controls of meal size
All factors relating to the direct contact of food to the gastrointestinal mucosal
receptors.
Become clear that indirect controls have the capacity to override direct controls
What is satiation?
What brings an eating episode to an end
What is satiety?
Inter-meal period
What is satiety cascade?
Satiety cascade showing the
relationship between satiation
and satiety and some mediating
psychological and physiological
processes.
Increase of hunger-> eat -> increase of fullness until satiation then fullness for a while satiety
What are the characteristics of food?
- Energy density (ED; Kcal/g)
- Liquids versus solids
Outline energy density
- Energy density (kcal/g)
- People tend to keep volume constant when consuming food (Rolls et al. 2002, 2004)
- Large portions of energy dense food facilitate overconsumption
- Reductions in ED are associated with reduced energy intake (Bell et al. 1998, Stubbs et al. 1998,
Rolls et al. 1999) - Altering ED allows individuals to keep portions constant but consume fewer kcal
whilst maintaining satiety.
How can we reduce energy density of diets?
- Incorporating water - Fruits and vegetables
- Air (industry)
- Reducing fat/ sugar (individual/ industry)
- Method of cooking
How does liquid versus solid food affect energy compensation?
Energy compensation is the adjustment of energy intake following the
ingestion of a particular food
Energy compensation is lower with liquids than solids
Exception of soup!
➢Textural properties e.g. short oral residency time, speed of consumption,
water content also cognitive aspects e.g. drinks related to thirst not hunger
Role of alcohol consumption in excess energy intake
- Consumed in liquid form
- Least satiating macronutrient
- Efficiently oxidised at the expense of
fat - Additive to total daily energy intake –
passive overconsumption - Stimulates intake – active
overconsumption - Associated with poorer food choices –
interaction with type of beverage
consumed - Pattern of consumption is important
What are the characteristics of the food environment?
- Variety
- Portion size
- Distraction
What is the effect of variety?
- Variety often improves dietary quality – incorporated in the NHS eat well guidelines.
- Variety can promote energy intake.
Exposure to a variety of foods undermines development of meal satiation.
Following the consumption of a food, there is a reported decrease in the
pleasantness of the appearance, smell, taste, & texture of that food, whilst
other foods remain pleasant. - Named “Sensory-specific satiety” (Rolls, 1986) or satiation (SSS)
- Sensory = taste, smell, sight, texture
Outline portion size effect
Evidence consistently demonstrates that consumption of large
portion sizes of energy dense (ED) food facilitates over
consumption – Portion size effect (PSE)
In the absence of compensatory effects, large portion sizes of
ED food may be contributing to the increased prevalence of
overweight and obesity
Synergistic effect between portion size and ED.
Portion size effect persists over days/ weeks in children and adults.
Can we improve diet through portion sizes?
- Mathias (2012): serving larger portion sizes of F&V to pre-school children increased
intake but did not affect intake from the rest of the meal - Savage et al. (2012): reducing the portion sizes of children’s meals promoted intake
of fruit and vegetables - Rolls et al. (2010): serving more vegetable at a meal reduced energy intake in adults
What is the effect of distraction?
Watching TV:
* Hetherington et al. (2006) reported a 14% increase in intake when
participants watched TV whilst eating versus eating alone.
Eating with others: Social facilitation
* Food intake can increase between 40 – 70% (De Castro 1990, 1991, 1994)
* Increased perceived pleasantness (Bellise & Dalix 2011)
* Ruddock et al. (2019) eating with others increases
food intake relative to eating alone. Effect is
moderated by the familiarity of co-eaters.
What are the psychological factors of eating?
- Dietary restraint
- Stress
- Sleep
- Reward sensitivity
- Weight stigma
Effect of dietary restraint on eating behaviour
Disinhibited eating behaviour (opportunistic eating) is
not only associated with weight gain and obesity, less healthful food
choices
What is the effect of stress on eating behaviours?
Stress and eating behaviours in children and
adolescents; systematic review and meta-analysis.
* Impact of stress on eating behaviours occurs around ages 8-9 yrs
Effect of sleep on eating behaviours
Insufficient sleep duration and quality associated with increased risk of
obesity, insulin resistance and T2DM
* Sleep restriction led to changes in appetite regulating hormones and
increased hunger.
* Sleep restriction led to increased insulin resistance and elevated diabetes
risk, through multiple mechanistic pathways.
* Behavioural sleep extension and sleep quality improvement may help
reduce obesity and diabetes risk.
- Beaver et al. (2006): Correlation between sensitivity to reward traits and
neural responses to palatable food images - Burger et al. (2011): Increased body weight associated with enhanced
responsiveness to visual images of food
How did Sweden increase healthy life expectancy?
In 2003 the parliament in Sweden adopted a new public health policy “to create the social conditions for good health, on equal terms, for the entire population”
Instead of using treating diseases as paradigm they use determinants as starting point
Determinants are factors in both the structure of society and people’s living conditions and lifestyles that are either good or bad for health.
What is multimorbidity?
Presence of two or more chronic conditions
> 50% of those aged over 65 have multimorbidity
10M have multimorbidity
Multimorbidity is the leading cause of service use
£7 in every £10 of the total health and social careexpenditure are on chronic conditions
What is frailty?
Accumulation of deficits across organ systems
Impaired ability to respond to an adverse event
25-50% of the over 80s
1.7M in UK are clinically frail, due to double by 2045
A patient with frailty costs
2x GP in appointments.
4x hospital admissions
10X in social care
What is geroscience?
A new discipline to meet the challenge of an ageing population
Studies ageing
What is biological ageing?
Accumulation of damage to cells and tissues leading to progressive loss of function
What is senescence
What can increase healthspan
Exercise
What is system medicine
The concept behind systems medicine is that there are common genes and pathways among diseases and diseases appear in clusters,
Each cluster is underpinned by a common mechanistic origin.
These clusters radically change what we call a disease.
The underlying causal molecular mechanism becomes the disease definition
Drugs are developed targeting the molecular mechanism for specific clusters of diseases.
Size of problem
Effectiveness of intervention
Whether there are alternatives
Whose “fault” is the disease?
Is this a health problem?
Is the NHS responsible for this problem?
Special population - e.g. preterm babies
Is there a large payback from treatment?
Is this disease population particularly “deserving”?
Priority setting and the NHS constitution
The NHS provides a comprehensive service, available to all
Access to NHS services is based on clinical need, not an individual’s ability to pay
The NHS is committed to providing best value for taxpayers’ money
What is scarcity?
The basic economic problem is scarcity:
Resources are limited
The desire for goods and services exceeds current resources
Choices cannot be avoided, therefore decisions have to made
No country treats all treatable ill health – all countries ration health care
Opportunity cost
The opportunity cost of a choice is the lost benefit of the best alternative - i.e. the sacrifice in terms of the benefits forgone from not allocating resources to next best activity.
A health example might be: spending spare budget on hip replacements means it can’t be spent on mental health services. The opportunity cost is the lost benefit of the mental health services.
Economic efficiency
Economic efficiency is achieved when resources are allocated between activities in such a way as to maximise benefit.
In healthcare this means aiming to get the maximum health benefit from our fixed budget.
Economic evaluation
Economic evaluation is the assessment of economic efficiency
- Economic evaluation is a comparative study (between two or more interventions) of the costs and benefits of health care interventions for some given disease
- Costs and benefits are analysed in terms of their ‘increments’ or differences between the interventions
- We are usually comparing something new with something we are currently doing
- We ask: are the incremental benefits of a new treatment (compared with the existing treatment) worth the incremental costs?
Natural units as a measurement of health benefit
Change in something measured in “natural units”
blood pressure
pain score
number of cases detected
walking distance
blood cholesterol
Comparison between diseases is difficult
QALYs as a way to measure health benefit
The Quality Adjusted Life Year (QALY)
- Combines length of life with quality of life
- How do we measure quality?
- We use the idea of “utility” as a measure of quality
- Someone’s “utility” for a health state is how strongly they value that health state
- Full health is defined to have a utility of 1
- Being dead is defined to have a utility of 0
- States worse than death have negative utility values
How to calculate QALYs?
Length (years) x quality (“utility”) weighting (0 to 1 scale)
1 year perfect health (i.e. utility of 1) = 1 QALY
2 years with utility of 0.5 = 1 QALY
8 years in utility of 0.75 = 6 QALYs
Monetary value as a way to measure health benefit
Health is measured in monetary terms
- This draws on the idea of “willingness to pay”
- How much is someone prepared to pay for some health benefit?
- Difficult to determine in a healthcare system that is free at the point of use
- Has various problems: richer people might be willing to pay more than poorer people. Does this mean their health is more valuable? Is this fair?
How do we measure health costs?
Monetary units (£ in the UK)
- All relevant costs should be measured, e.g.
- Drug treatment
- Hospital stay
- Outpatient appointments
- We are usually interested in the costs to the NHS (and not any costs to the patient)
What are the four types of economic evaluation?
Cost effective analysis
Cost utility analysis
Cost benefit analysis
Cost minimisation analysis
Outline cost-effectiveness analysis
Outcomes measured in natural units
Costs in monetary units
Outline cost-utility analysis
Outcomes measured in QALYs
Costs in monetary units
Outline-benefit analysis
Outcomes measured in monetary units
Costs in monetary units
Outline cost-minimisation analysis
Outcomes, measured in any units, are equal in both treatments.
Therefore, just minimise cost.
What is The Incremental Cost Effectiveness Ratio (ICER) ?
The ICER is the incremental cost of one treatment versus another,
divided by the incremental benefit of one treatment versus another.
ICER equation
Cost New - Cost Old .
Benefit New - Benefit Old
NICE
Once an economic evaluation has been completed it is up to the National Institute of Health and Care Excellence (NICE) to decide if a new treatment should be available on the NHS (in England and Wales)
How do we value a QALY?
When we fund a new more expensive treatment, we need to stop funding another treatment, somewhere else in the NHS to pay for it – the overall NHS budget is fixed
NICE thinks that any services that are closed down to fund new services probably generate benefits at a cost of about £20,000 per QALY gained
Taking £20,000 from somewhere else in the NHS to fund a more expensive drug therefore loses 1 QALY
So, it only makes sense to fund new things if we get at least 1 QALY per £20,000
Equivalent to requiring the cost to be less than £20,000 per QALY gained for something to be cost-effective
£20,000 is called the “NICE threshold”
What is equity?
Society is concerned with more than just efficiency
Equity is concerned with the fairness or justice of the distribution of costs and benefits
Economists are clear in principle about the definition of efficiency. There are, however, opposing views about what is ‘fair’
Such considerations are very difficult to quantify and so tend to enter the decision making process much more subjectively
Equity is just as important as efficiency
There is usually a trade-off between equity and efficiency
What is rationing?
A fixed budget means that we cannot afford everything
We must make choices
If we fund treatments that cost more than the threshold, overall health goes down – we lose more than we gain
We therefore choose not to fund some treatments
This gets called “rationing”
It is seen as very very bad, even though we do it to maximise overall health
- A fixed budget means that we cannot afford everything
- We must make choices
- If we fund treatments that cost more than the threshold, overall health goes down – we lose more than we gain
- We therefore choose not to fund some treatments
- This gets called “rationing”
- It is seen as very very bad, even though we do it to maximise overall health
Exercise
“activity requiring physical effort, carried out to
sustain or improve health and fitness”
▫ a subcategory of physical activity that is
planned, structured, repetitive, and aims to
improve or maintain one or more components of
physical fitness.
Physical activity definition
▫ “any bodily movement produced by skeletal
muscles that requires energy expenditure”
▫ includes exercise as well as other activities which
involve bodily movement and are done as part of
playing, working, dancing, active
transportation, house chores, recreational
activities etc.
How is physical activity measured?
MET- metabolic equivalent
1 met- metaboilic rate at rest
Ways of measuring physical activity
- Self report (e.g. IPAQ, WSQ)
- Direct observation
- Heart rate monitoring
- Accelerometry
- Inclinometry
- Portable indirect calorimetry
- Doubly labelled water
Ways of measuring fitness
Cardio Pulmonary Exercise Testing
▫ (CPET/CPEx)- gold standard
Impact of not being physically active vs being physically active in older adults
- Sarcopenia + bone loss → frailty
▫ Hip fracture: average 83.5years
▫ 30% mortality at 1 year - Inverse association b/t weight bearing exercise +
hip/spine fracture - strength & balance-fall prevention
Is obesity bad for your health?
- 30,000 deaths/year
- 10 year reduction lifespan
- £4.7 billion/year (inactivity 8.2 billion)
- Mortality increases by 30% every 5kg/m2
▫ 57 observational studies (900,000 people)
▫ vascular disease
▫ renal
▫ diabetes
▫ respiratory
▫ cancer
Does fitness offset the risk of obesity?
- True for over weight & obese individuals
- Partially, being ‘ideal weight’ & fit is still the aim
- Being fit & obese is healthier than slim & unfit
- Improvements in fitness (in the overweight/obese)
do improve health (mortality)
Is sedentary behaviour bad for your health
- Mostly cross-sectional data, but prospective studies are
emerging - Sedentary behaviour appears independently associated
with: - higher all-cause mortality
- higher CVD mortality
- increased risk of:
obesity,
type 2 diabetes,
cancer
Exercise prescription
Frequency
Intensity
Type
Time
Key challenges of an aging population
strains on pension and social security systems;
increasing demand for health care;
bigger need for trained-health workforce;
increasing demand for long-term care;
pervasive ageism that denies older people the rights and opportunities available for other adults.
