Introduction
Epidemiology is the medical science that asks what causes a disease and how it spreads among people; it studies the distribution and determinants of disease in human populations. Its main aim is to find and establish a causal relationship between an exposure to a risk factor and an outcome, using epidemiological studies. This topic covers the burden of disease: what it is, which diseases are socially significant, how it is measured (HALE, QALY, DALY), the epidemiological transition, and the main risk factors.
Disease burden
Disease burden is the impact of a health problem as measured by financial cost, mortality, morbidity and other indicators. It looks at health problems which:
- determine to the greatest extent the profile of mortality and morbidity in a given country or region;
- are associated with the greatest impact (damage) for patients, their families and the whole society.
Socially significant diseases are those classes of diseases and separate illnesses which rank highest in defining the morbidity and death-rate profile of a country (e.g. hypertension, diabetes, neoplastic disease). They are prevented by raising the health culture of the population, developing health promotion, and good organisation of the GP service with examinations conducted by the family doctor.
Terminology: the term "socially significant disease" is preferred to "disease burden", because any condition has some burden and some have more than others. A high burden means high mortality, high costs, etc.