Swedish Adoption Twin Study of Aging (SATSA)
SATSA was started in 1984 and is comprised of several longitudinal components. A comprehensive questionnaire was sent in the first component to all twins separated at an early age and reared apart and a control sample of twins reared together from the Swedish Twin Registry. The questionnaire included items concerning rearing, adult, and working environment, health status, health related behaviors (e.g. alcohol, tobacco, and dietary habits) as well as attitude and personality measures. The questionnaire phase is repeated every third year: More than 2,000 twins have responded to questionnaires sent in 1984, 1987, 1990 and 1993. In the second component a subsample of approximately 150 twin pairs reared apart and 150 twin pairs reared together have participated in four waves of in person testing including a health examination, structured interviews/tests of functional capacity, cognitive abilities, and memory. The first three waves were at 3 year intervals; the fourth was initiated in 1999 and fifth in 2002. Data from SATSA are analyzed for the purpose of examining the relative importance of genetic and environmental factors for individual differences in aging related processes. Longitudinal changes as well as the relationships within and among domains (e.g. the importance of genetic effects for mediating the relationship between physical health and cognitive decline) for the elderly are of primary interest.