Lecture 1 - Non-infectious diseases - CVD and stroke Flashcards
What is epidemiological transition?
Changes in level and causes of mortality > decline of total mortality - decreasing mortality of infectious and deficiency diseases you increase the relative role of non-communicable diseases - cancer/CVD
What is epidemiological transition affected by?
Socio-economic status, demographic, technological, cultural, environmental and biological changes
What diseases have disappeared, appeared and re-emerged?
Smallpox -disappeared
HIV - appeared
TB - re-emerged
What is the change in stomach cancer and lung cancer?
Stomach: decrease
Lung: rise and fall
What has stroke shifted to?
Stroke > heart disease
How many deaths worldwide has CVS caused in 2010?
15.6 million - 29.5% of all deaths in 2010
What are the main diseases in CVD epidemiology?
CHD and stroke, rank 1st and 2nd amongst cause-specific mortality worldwide
Where do most CVD deaths occur?
In developing world rather than developed
Why is the burden of non-communicable disease likely to rise?
Demographic (aging popn) and epidemiological transitions
Where is there low incidence of mortality from CHD?
Japan, UK and western countries
Where is there high incidence of mortality from CHD?
Formerly socialist economies of Europe and Middle East
In which sex are rates for CHD higher?
MEN> women (although gap shrinking in some countries)
Where has there been a rise in CHD and stroke mortality?
Formerly socialist economies of Europe and South Asia - declining in many countries
What factors do the epidemiological patterns indicate underlie the variation of CVD risk worldwide?
Environmental > genetic
What are the 3 main risk factors for CVD?
High BP Tobacco smoking High serum cholesterol levels Obesity Underweight and unsafe sex
What worldwide trends will increase the burden of non-communicable disease e.g. metabolic disorders and diabetes?
Overweight and obesity
How many deaths worldwide are caused by cancer in 2010?
> 25% of deaths in many countries
15.1% of deaths worldwide
8 million people
How many of these cases are more likely to occur in less developed countries?
60%
Which cancers are the most commonly diagnosed?
Lung, breast and colorectal
Which cancers are the most common cause of death?
Lung, liver and stomach
What happens to cancer rates in migrants?
They converge towards local cancer rates over time - due to modifiable risk factors
How many cancers are preventable?
One third - through number of lifestyle and environmental approaches
What is the largest preventable cause of cancer in the world?
SMOKING
How many years can cancer take to appear and why is this relevant?
20 years - so current cancer rates are affected by changes and exposures that took place in the past
What are the major carcinogens?
Tobacco
Alcohol
Air pollution
Occupational agents
What is the concern of clinical medicine?
Cases of disease and disease burden for individual
What is the concern of epidemiology?
Disease rates and burden of disease in populations
What is epidemiology?
Study of distribution and determinants of health-related states or events in specified popn and the application of this study to control health problems
How are epidemiological trends measured?
Time - rate/popn over time period
Person - age (adjusted to remove effect of aging popn), gender, race
Place - country
How many strokes and HD cases are attributable to raised BP?
62% of all strokes
49% of all HD
What are the estimates for both CHD and stroke in developing countries?
Doubling mortality so approx. 69% and 76% of all deaths from these causes worldwide
How have number of cancer diagnoses reduced?
Pap smears, cigarette smoking reduction, HPV vaccine
What are the probabilities of cancer?
1 in 2 men, 1 in 3 women
What is incidence?
Number of new cases
What is prevalence?
Number of cases at a particular time
What is mortality?
Number of deaths
How do changes in mortality an incidence over time reflect?
Changes in exposure, diagnosis, screening, treatment (only mortality)
For which cancers has mortality rate fallen?
Most, particularly stomach and cervical
How many cancer deaths due to smoking?
1 in 4
How many lung cancer deaths are caused by smoking?
90% in males
80% in females
By how much does smoking cessation decrease life risk for lung cancer?
Stopping at 30 decreases risk of lung cancer mortality by 10%
What are the avoidable causes of cancer?
Tobacco, alcohol, reproductive and sexual behaviour, occupation, pollution, medicine, geophysical factors, infection, diet
Where does arsenic cause cancer?
Skin, lungs urinary bladder and kidney
Also causes thickening and pigmentation change of the skin
Infections by viruses, bacteria and parasites causes how many cancers worldwide?
18% of worldwide cancers
4% of cancer in UK
