Epidemiologic Transition: Changes of fertility and mortality with modernization Abdel Omran. The Epidemiologic Transition: A Theory of the epidemiology of population change. Milbank Quarterly. 1971;49: pdf

Lecture n Epidemiologic Transition n Geographic Studies, what do they tell us?

Charles Darwin Evolution of Species Abdel Omran Evolution of Disease

Epidemiology  Psychiatric Epidemiologists  Diabetes Epidemiology  Cardiovascular Epidemiology  Cancer Epidemiology  Infectious Disease Epidemiology

Instead at looking at individual diseases, we need to look at the patterns of diseases

Mortality is the fundamental factor in the dynamics of population growth and causes of death. Mortality has no fixed upper limits. Thus if fertility approached its upper maximum, depopulation would still occur.

During the epidemiologic transition, a long-term shift occurs in mortality and disease patterns whereby pandemics of infection are replaced by degenerative and man-made diseases...

Age of Pestilence and Famine Characterized by high mortality rates, wide swings in the mortality rate, little population growth and very low life expectancy

Age of Receding Pandemics Epidemics become less frequent, infectious diseases in general become less frequent, a slow rise in degenerative diseases begin to appear

The shifts in disease patterns in the 19th century were primarily related to changing SES. With the 20th Century more related with disease control activities independent of SES: e.g. Mexico, China

Epidemiologic Transition in Developing and Developed Countries

35 years 14 years

Population Life Expectancy Infection CA CHD Other Violence Increasing Life Expectancy and Causes of Death

Epidemiologic Transition Mortality Rates Infectious Diseases NCD

Death Rates for TB in England and Wales

TB Bacillus Identified Chemotherapy BCG Vaccination

Death Rates for Measles in Children in England and Wales

Immunization begun

Epidemiologic Transition Mortality Rates CA CHD NIDDM Trauma

Importance of Geographic Patterns

Incidence of Stomach CA Males

Breast Cancer Incidence Females

CHD Death Rates Males, aged 45-54

Cirrhosis Death Rates, Males, aged 45-54

High Incidence of NCDs in Developing Countries ] Possible Infectious Etiology Macronodular Cirrhosis Macronodular Cirrhosis Hepatocellular Carcinoma Hepatocellular Carcinoma Rheumatic Heart Disease Rheumatic Heart Disease Iron deficiency anemia Iron deficiency anemia ] Related to Nutrition Deficiency Endemic Goiter Endemic Goiter Malnutrition Related Diabetes. Malnutrition Related Diabetes.

High Incidence of NCDs in Developed Countries Cardiovascular Cardiovascular CHD CHD Deep Vein Thrombosis Deep Vein Thrombosis Respiratory Respiratory Emphysema Emphysema Lung CA Lung CA Female Genital Female Genital Endometriosis Endometriosis Endometrial CA Endometrial CABreast Breast CA Breast CA Fibrocystic Disease Fibrocystic Disease Male Genital Male Genital Prostrate CA Prostrate CA Metabolic Metabolic NIDDM NIDDM

Back to Nature  Improved Physical activity  A Healthier Diet, less saturated fats, more fiber  Less Stress

Transition  Nomads  Farmers  Urban 45 yrs 60 yrs 70 yrs

1960 Urban Rural USA Developing Countries ruralurban

2006 Urban Rural USA Developing Countries rural urban

Causes of Death n Age Accidents Accidents CA CA CHD CHD n Age CHD CHD CA CA Accidents Accidents Age Accidents CHD CA Age CHD CA Accidents DevelopedDeveloping

48 Health Transition – Developed Countries n Currently, most developed countries are in the third stage of the health transition: –fertility rates are low –causes of diseases and deaths have shifted from infectious to chronic diseases.

49 Health Transition – Developed Countries … n All developed countries in Europe, North America and Asia are seen as having arrived in the latter stage of the health transition in the 1970s, although there were large differences with regard to timing, particularly in the onset the decline in fertility. In these countries, declining fertility rates and increased life expectancy have led to the ageing, or so ‑ called 'greying', of the population. In these countries, declining fertility rates and increased life expectancy have led to the ageing, or so ‑ called 'greying', of the population.

50 Health Transition – Developing Countries n The health situation in developing countries varies greatly from one country to another. n In most, there is still very low life expectancy; this is due largely to malnutrition and the lack of safe drinking water, which are compounded by poor healthcare facilities. In other countries, however, particularly in Asia and Latin America, chronic diseases have now become more important than infectious diseases. In other countries, however, particularly in Asia and Latin America, chronic diseases have now become more important than infectious diseases.

51 Health Transition – Developing Countries … n The same large variation is reflected in the demographic situation. n In countries such as China and Thailand fertility rates are very low; in others they are very high. n Due to sub ‑ national differences of an economic, social or ecological nature, there may also be large differences within a single country.

52 Health Transition – Developing Countries … n It is widely believed that, with increasing economic growth, developing countries will follow the same pattern of health transition as Europe and North America. Many countries, especially the poorest, will not 'trade' infectious diseases for chronic diseases; instead, they may even suffer a 'double burden' of disease. Many countries, especially the poorest, will not 'trade' infectious diseases for chronic diseases; instead, they may even suffer a 'double burden' of disease.