Transition sanitaire : tendances et perspectives.

Abstract

Pendant des millénaires, l’espérance de vie des hommes n’a sans doute jamais excédé 25 ou 30 ans. À partir du XVIIIe siècle, tout a changé sous l’effet de la transition démographique, ce processus historique qui a permis à l’humanité de passer d’un régime ancien, où une forte fécondité équilibrait les pertes dues à une forte mortalité, à un régime nouveau où la mortalité a tellement reculé qu’il suffit d’à peine plus de deux enfants par femme pour assurer le remplacement des générations. L’idée générale d’une transition sanitaire englobe aujourd’hui non seulement la donne épidémiologique mais aussi les différentes réponses de la société aux questions de santé. Deux questions essentielles se posent pour l’avenir. Peut-on encore espérer d’importants progrès de l’espérance de vie ? Et quel rapport le vieillissement démographique entretient-il avec l’état de santé des populations ?

For two centuries or so in Europe and more recently in the developing countries, major progress have been occurring in the human life expectancy especially thanks to the success of the fight against infectious diseases. This decisive change used to be known as the epidemiological transition. However, life expectancy would not have continued to increase during the last three or four decades in the industrialised countries, without important progress on new fields and especially in cardiovascular diseases, the reason why we progressively moved towards the broader concept of health transition, including not only epidemiological changes but also the diversified type of response from the society towards health problems. In the same time, the demographic consequences of the increase in life expectancy have changed. In the first stage, till the sixties about, the major decline in mortality was observed among young children the consequence of which was to moderate the population ageing due to the fertility decline. When life expectancy reaches about 60 years the reverse phenomenon occurs: every further reduction of mortality affects mainly the adult and old part of the population and reinforces the demographic ageing process. What could happen in the next decades? Can life expectancy continue increasing? Until what limit, if any? With what consequences for demographic ageing? No doubt that the XXIst century populations will be very different from any we knew until now.