1 / 17

Sick Individuals and Sick Populations: High Risk and Population Based Approaches

Sick Individuals and Sick Populations: High Risk and Population Based Approaches. Sir Geoffrey Rose. British Epidemiologist A Former Clinician Foundational Contribution to Public and Population Health The Principles of Population Strategies. The Strategy In Rose ’ s Time.

brand
Download Presentation

Sick Individuals and Sick Populations: High Risk and Population Based Approaches

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Sick Individuals and Sick Populations: High Risk and Population Based Approaches

  2. Sir Geoffrey Rose • British Epidemiologist • A Former Clinician • Foundational Contribution to Public and Population Health • The Principles of Population Strategies

  3. The Strategy In Rose’s Time • A Clinical Strategy – Physician Strategy • People were sick and became Patients • Intervention usually when the disease was entrenched and often well advanced • Prevention was not as important a concept • Sometimes Patients are created e.g. HBP • Public Health Strategies were educational and addressed those at risk

  4. Rose’s Questions • “Why do some individuals have hypertension”? • “Why do some populations have more hypertension” and other less? • What is responsible for the case? • What is responsible for the incidence in a population?

  5. Bulletin of WHO 2001, 79(10)

  6. Distribution of Systolic BP in two Populations • In both populations if you only ask what is associated with the cases then the answer will be much the same – genetics, environment, behaviour • Looked at in isolation the greater question is obscured – “why is there much more elevated BP in London and much less in Kenya

  7. What is Normal • If we understood the factors that lead to lower BP in Kenya then there is no reason why the application of those factors in London could not produce the same result • The conclusion is: - the population distribution can be shifted – in this case the curve could move to the left – the “normal”of this population need not be accepted as normal and indeed it may not be OK – and could potentially look like that of Kenya (or closer to that of Kenya) and thus make for a healthier society

  8. What do we Conclude? • We need to be able to observe at population levels and not just individual levels • The find the determinants of incidence and prevalence rates, we need to study the characteristics of populations, not characteristics of individuals. • Accepted normal values may not be normal and they may not be OK

  9. What do we Conclude? (2) • Curves of Risk can be shifted • Cardiovascular Disease is a largely preventable disease • We can confirm this by population trends e.g. Canada CAD mortality declines • Migration Patterns – Asians to North America – curve shifts to the right – adopt lifestyles of the new country

  10. Learning from The Cholesterol Distribution Curve • Most of the excess deaths occur in the population in the middle of the curve at moderate values • There is high mortality at the high levels but there are far fewer people • In a population a large number of people at smaller risk will give rise to more cases of disease than a small number of people at high risk

  11. The Conclusion • High risk levels of a factor may affect relatively few people in the population • A very large number of people exposed to a lesser or moderate risk leads to the majority of the cases in the population

  12. The Case for a Population Strategy • If our health system focuses only on those who are at high risk or are sick; if we employ only clinical strategies we will miss the majority that contribute most to the overall mortality • A population preventive strategy that seeks to move the entire population distribution curve to the left is essential

  13. The Population Approach • Both populations and high risk groups plus vulnerable population • Creates environments supportive of health • Focuses on health promotion and disease prevention • Works through partnerships and coalitions • Includes inter-sectoral and interdisciplinary groups and organizations • Uses healthy public policy development and community mobilization as major tools.

  14. What Can We Conclude? • Since most cases arise in the middle of the curve • Since population curves can potentially shift • Since small changes which occur over an entire population produce great population benefits (though small individual benefits) • Therefore a population health approach is essential if risk is to be reduced and consequently morbidity and mortality

  15. The Context • Social Motivation: • Change social values/norms • Marketing (social) • Marketing as a challenge • $$$$$ to influence behaviour • To influence mass behaviours then must influence mass determinants and they are economic and social

  16. Conclusion Rose has lead us to an understanding of: • Observing populations to understand the reasons for incidence and prevalence is essential • Risk distribution at a population level can be improved (move the curve) • Most cases do not arise from the high risk group • To improve health need a population health strategy to complement a high risk strategy

More Related