Definition of the ‘health transition’ Trends of disease patterns in populations

1. Definition of the ‘health transition’ • Trends of disease patterns in populations • The 4 stages of the epidemiological transition • The cardiovascular disease transition • Engines of the health transition • Urbanization, demographic, lifestyle, socioeconomic and health care • Other determinants of NCDs Impact of NCDs on public health • Predicted trends in disease patterns, ‘Global Burden of Disease’ • The double burden of disease • Impact of NCDs on public health • Evidence for the preventability of CVD • Strategies for the primary prevention of CVD • Public health response to emerging CVD IUMSP-GCT

2. The health transition predicts an unprecedented epidemic of NCD/CVD in developing countries • Is there enough evidence that CVD can be prevented at the first place ? Yes!! IUMSP-GCT

3. Primary prevention of coronary disease through diet and lifestyle (Nurses’ Health Study, 89141 women )

4. Low risk factor profile is associated with low CVD mortality (several US cohorts)

5. Risk status, income and CVD mortality: low RF profile predicts low CVD mortality irrespective of income • Men aged 35-57 • MRFIT IUMSP-GCT

6. CVD risk factors: large potential for prevention - Non modifiable RF: age, sex, history Behavioral RF: Physiological RF: Endpoints: Smoking Hypertension • Heart disease Unhealthy diet • Stroke Cholesterol (salt, fat, fruit & veg ) • Vascular disease Diabetes Sedentary lifestyles • Some cancers Obesity Resp . disease Socio economic & - cultural determinants Early life characteristics * modifiable IUMSP-GCT

7. Cardiovascular disease: a multifactorial disease • Reduce blood pressure • Reduce serum cholesterol • Reduce the number of smokers • Reduce the number of persons with overweight • Ensure healthy diet (~change diet) • Prevent (and control) diabetes • Improve social conditions IUMSP-GCT

8. Definition of the ‘health transition’ • Trends of disease patterns in populations • The 4 stages of the epidemiological transition • The cardiovascular disease transition • Engines of the health transition • Urbanization, demographic, lifestyle, socioeconomic and health care • Other determinants of NCDs • Predicted trends in disease patterns, ‘Global Burden of Disease’ • The double burden of disease • Impact of NCDs on public health • Evidence for the preventability of CVD • Strategies for the primary prevention of CVD • Public health response to emerging CVD IUMSP-GCT

9. The health transition predicts an unprecedented epidemic of NCD/CVD in developing countries • Do we know enough to prevent this CVD epidemic in the first place? Yes!! • Do we know enough to make a difference? Yes!! IUMSP-GCT

10. The health transition in developing countries: which possible responses ? 4 engines for heath transition: • Demographic (populations get older) • Not modifiable • Lifestyle-epidemiologic (age-specific risk factor rates change) • Modifiable • Socio-economic (differential risk factors levels across SES) • Modifiable • Health services (access/use of preventive & curative services) • Modifiable IUMSP-GCT

11. Linear relation between relative risk of CVD and risk factor level in populations (the example of diastolic BP and stroke, Eastern Asia) IUMSP-GCT

12. Relative risk, RF prevalence and attributable fraction: low impact on strategies limited to high risk patients (the case of blood pressure and CHD)

13. Population and high risk preventive strategies

14. Strategies to prevent the emergence of NCD/CVD Primary prevention (limit the number of new cases) Population strategy • Public health approach • Targets population High risk strategy • Clinical management • Targets individuals IUMSP-GCT

15. Public health approach vs. high risk strategy High-risk Population Advantages · · Radical ( incidence) Benefit for individual large ¯ Advantages · · Easy to understand, hence Potential large benefit motivation and rewards for · Cost effective (policy) individuals · Can target unaware · Needs person's cooperation population groups Limitations · · Need for mass change is hard Impact on total burden small to communicate Limitations · Often misused · Interventions other than · Costly (screening) policies hard to implement · Palliative (does not solve · Benefit for individual small, overall problem, 'rescue') hence weak motivation of · Distracts from population individuals and physicians approaches · Interventions can challenge vested interests/societal norms

16. Estimated stroke/CHD deaths that could be averted in 2020 by applying ‘population’ and ‘high-risk’ preventive strategies Combined population and high risk approaches ~ additive

17. Yield of a screening and treatment (high risk) strategy at population level: long-term compliance to a 1-tablet/day antihypertensive medication*

18. Definition of the ‘health transition’ • Trends of disease patterns in populations • The 4 stages of the epidemiological transition • The cardiovascular disease transition • Engines of the health transition • Urbanization, demographic, lifestyle, socioeconomic and health care • Other determinants of NCDs • Predicted trends in disease patterns, ‘Global Burden of Disease’ • The double burden of disease • Impact of NCDs on public health • Evidence for the preventability of CVD • Strategies for the primary prevention of CVD • Public health response to emerging CVD IUMSP-GCT

19. Areas for public health interventions & policies to prevent and control NCD/CVD in developing countries • Reduction of sodium consumption • developed countries: ~75% in processed food; developing countries: often most from ‘discretionary’ use (opportunity) • Food policies promoting healthy foods • Interventions/policies to promote physical exercise • Tobacco control • legislation, Framework Convention of Tobacco Control • Health education integrated in school curriculum • In all instances, need for multisectoral approach

20. Constraints for NCD/CVD prevention in developing countries • Limited recognition/available data of major NCDs • Double burden of disease • Lack of commitment at international level • Prevention not taken seriously (market pressure favoring therapy) • Failure to influence the policy of government departments • Conditions like stroke/CHD considered diseases for the specialist • Health care needs not addressed ‘prospectively’ by existing health systems (lack of perspective of ‘health transition’) • Costs are rising and resources are dwindling

21. Preventing NCD/CVD in developing countries: a window of opportunity • Relatively low levels of some risk factors in many developing countries • Opportunity for prevention in the first place (‘primordial prevention’) • Unlike for western countries (where CVD epidemics was understood at its peak and addressed mainly through case-management • Prevention is the best option as an approach mainly based on case-management is not affordable for most DC • Monitor trends in CVD risk factors IUMSP-GCT

22. Global strategy for the prevention and control of NCD/CVD in developing countries Prevention in the first place • reduce major risk factors through population strategy • targeted high risk strategies Case management • identify and promote cost-effective and affordable interventions Surveillance • assess the patterns and trends of main risk factors (mortality: the past; morbidity: the present; risk factors: the future)

23. Health transition and emerging NCD/CVD in developing countries: implications for the public health response • The paradigm of the health transition provides an evolutionary perspective which transcends the limitations of confined cross-sectional views of the CVD epidemic and argues towards strategic choices of policies and programs which take into account the present as well the future burdens of CVD. • The direction of the epidemic in developing countries is clear and the dimensions of the future burden can be predicted by combined demographic and economic models. • The case for preventive public health action becomes stronger when it is recognized that the future health care demands of a full-blown epidemic will be well beyond the capacity of the public health system.

24. Health transition and emerging NCD/CVD in developing countries: the way forward • Reappraise the coming NCD/CVD epidemic • Apply the knowledge • Focus on primary prevention with focus on health policies • Target high risk strategies (hypertension, diabetes) • Identify and apply low cost and affordable interventions for case management • Set surveillance systems (particularly risk factors) • Need to strengthen capacity building, leadership, partnership