Epidemiology in aging research.

Epidemiology and Gerontology are relatively young scientific disciplines, both of which have had their own specific development in the past few decades. Only very recently, expertise from both fields has been brought together to extend and strengthen the spectrum of aging research. In this review, we outline the definition and methods of epidemiology and its historical development as a scientific discipline. We review and give examples of past and current contributions of epidemiology to aging research, and we outline the specific challenges, difficulties and opportunities encountered by epidemiologists in this field. We end up with an outlook on major challenges and opportunities for further development of epidemiology in aging research. We conclude that further integrative approaches with a particular emphasis on functional impairments are needed. Furthermore, the etiology of chronic diseases and impairments among the elderly cannot be studied by restricting the focus to health outcomes and their determinants at old age. Major efforts have to be made to incorporate measures of relevant determinants throughout the life span. Finally, epidemiologic methods should be more widely used for studies of medical and nursing care, and results of epidemiologic research need to be more effectively transferred into the practice of prevention.