Describing breast cancer in the population (Epidemiology) Flashcards
Risk Factors for breast cancer
Age
Overweight
Family history
High Alcohol Intake
Prolonged oestrogen exposure - early menarche, late first pregnancy, late menopause, oral contraceptive
Protective Factors
Breast feeding
Physically active
Breast Cancer Screening UK Policy?
- Aims to identify asymptomatic breast cancer
- Method: mammography to identify lesions which are then assessed via the triple pathway
- Offered to call women age 50-70 every 3 years
- Moderate risk due to family history - yearly from age 40
- Yearly MRI from age 30 for BRCA1 and 2
-Yearly MRI age 20 for TP53
Define Disease?
a deviation in bodily structure or function which places the individual at a biological or social disadvantage. Combination of biological abnormality, symptoms and social consequences
How do we measure the amount of disease caused by a condition at a population level?
Mortality
Morbidity
Health service use
Risk factors
Where do we collect mortality data from?
Census - includes summaries of mortality rates including causes
Death certificates - registration of deaths is compulsory, providing information on characteristics and cause of death
What is an Age Specific Mortality rate with pros and cons
Death rates over a narrow range of ages. e.g number of deaths to breast cancer in women age 65-75 per 1000 women
PRO
Allows identification of most vulnerable age groups
Allows us to compare with populations with similar age structures
Allow the monitoring of public health interventions targeting specific age groups
CONS
Do not take into account other factors affecting mortality such as age, race, socioeconomic status
May be affected by changes in population size within each age group over time, which can make it difficult to compare mortality rates between different time periods
Influenced by accuracy of death and age reporting between different geographic areas
What is the Age-standardised mortality rate with pros and cons
A summary of age specific mortality rates over a wider age range, which takes into account population structure
PROS
More meaningful comparisons between populations with different age structures- as they remove the effect of differences in the age distribution of the populations
Relevant for rapidly fatal conditions but not chronic and benign
Timely - made public within 1-2 years
CONS
Lless useful for monitoring changes in mortality rates over time within a specific population
Require data on the age distribution of the population, which may not always be available or accurate.
What are some limitations on mortality data in the UK?
Only moderately accurate for cause of death
Underreporting of deaths occurring outside care homes and hospitals
Not always relevant in assessing the burden all conditions, especially if not often fatal (such as breast cancer)
Cannot determine information on incidence and survival of disease
Delays in reporting
How do we assess morbidity?
Incidence rate - new cases.
PRO - study trends in disease, examines emerging cases
Prevalence rate- total cases (new and existing)
PRO - helps us define population burden of disease and health service needs
Point prevalence - “snapshot” of prevalence at a given moment
PRO - Good to assess chronic disease as it is less variable e.g prevalence of asthma
Period prevalence - number of people with the disease over a defined time
PRO- Good to assess acute disease (more variable) e.g asthma attacks vary month to month
Sources of data on morbidity?
Disease registration - voluntary information about specific diseases such as cancer, mental illness, occupational health disease
Disease notification - compulsory information about specific diseases such as infectious diseases, abortions, birth abnormalities
Health service utilisation - how much demand if put on the NHS due to condition
Hospital Episode Systems - record all NHS hospital admissions
GP data - diagnosis, treatment code and prescriptions
Social services - sickness absences and benefits
Routine Health Surveys - voluntary information, general household surveys gathering information on prevalence of chronic illness and lifestyle factors.
Pros and cons for disease notification?
PROS
High accuracy
Identify developing epidemics and disease clusters
Rapidly available to the public
CONS
Around 50% completeness
