ABSTRACT
This chapter discusses some of the epidemiological studies conducted in elderly populations. These studies are divided into two categories. The first represents the focus that researchers took in the past decade given that, until recently, researchers were primarily concerned with the brain. The second category reflects the principal interests that concern researchers, the main focus of which is behavior. Elderly people and the problems that they face have become a focus of great interest for scientists and international health organizations alike. A search on MedLine will reveal a plethora of citations related to aging, genetics, and epidemiology. The demographic transition that is taking place because of the decrease in the percentage of children, the reduction of the mortality rate, and the aging of the population necessitates some changes in the profile of disease and in health policies and services.
