SATSA - The Swedish Adoption/Twin Study of Aging

As the population ages, the vital question becomes: how to have a good old age? While some have a relatively comfortable old age, others experience considerable impairment and ill health.
Some estimate that extending the end of healthy aging by 3 years would have the equivalent impact of curing cancer. Hence, understanding the nature of aging and factors that predict healthy aging and delayed transition to increasing vulnerability and frailty is paramount to public health issues of aging.

Project description

The Swedish Adoption/Twin Study of Aging (SATSA) provides a unique opportunity to understand individual differences in aging. The twin design and the inclusion of twins reared apart makes it possible to study the importance of genetic and environmental factors that may underlie differing aging outcomes. Further, the broad spectrum of biological, psychological, and social domains assessed across the life span makes it possible to study patterns of change within and across domains and how these predict health and diseases of aging.

SATSA was started in 1984 and is comprised of several longitudinal components. To begin with, a comprehensive questionnaire was sent to all twins in the Swedish Twin Registry who were separated at an early age and reared apart and a control sample of twins reared together. The questionnaires include items concerning rearing, family, adult, and working environment, health status, health related behaviors (e.g. alcohol, tobacco, and dietary habits) as well as relationships, and personality measures. The questionnaires were sent again at 3 year intervals in 1987, 1990, 1993 and after a break again in 2004, 2007, and 2010. Thus far more than 2,000 twins have responded to at least one of the seven questionnaire assessments conducted between 1984 and 2010. Additionally there is information about midlife life style factors from the Swedish Twin Registry that were collected about twenty years before SATSA started.
In the second component a subsample of 861 individuals have participated in at least one wave of in-person testing (IPT). The first IPT started in 1986 and since then eight IPTs have been collected and the last wave will be collected during 2012-2013. The IPT includes a health examination, structured interviews, tests of functional capacity, and memory and thinking abilities. To date, over 76% of the sample has participated in 3 or more measurement waves.
At IPT9 a third component was added to SATSA, a measure of day-to-day fluctuations in memory and thinking abilities, and emotions. Information about social interactions is also collected. After the visit by the research nurses the twins fill out the day-to-day booklet during the next five days. This procedure will be repeated in IPT10. This will add information about small and short-term changes and more changes are supposed to indicate the beginning of poor health.
Data from SATSA can be used to study various aspects of aging. For example, the relative importance of genetic and environmental factors for individual differences in aging especially in cognitive and physical domains has been studied. A further main focus is to study changes within and across domains and which genetic and life style factors predict these changes. Given the wide spectrum of data from measured genes to social relationships collected over more than two decades we dare to say that SATSA is a unique study, with the possibility to answer many questions within gerontology and geriatrics.

Project leader

Financing: SATSA is supported by National Institute of Aging (AG04563, AG10175, AG08724), The MacArthur Foundation Research Network on Successful Aging, Swedish Research Council (825-2007-7460, 825-2009-6141, 825-3011-6182), and the Swedish Council for Working Life and Social Research (FAS) (97:0147:1B, 2009-0795).


The core research group contains researchers from Karolinska Institutet, School of Health Sciences at Jönköping University, University of Southern California, University of California - Riverside, and Indiana University Southeast.


Genetic and environmental influences on decline in biobehavioral markers of aging.
Finkel D, Pedersen NL, Reynolds CA, Berg S, de Faire U, Svartengren M
Behav. Genet. 2003 Mar;33(2):107-23

Association between depressed mood in the elderly and a 5-HTR2A gene variant.
Jansson M, Gatz M, Berg S, Johansson B, Malmberg B, McClearn GE, et al
Am. J. Med. Genet. B Neuropsychiatr. Genet. 2003 Jul;120B(1):79-84

Genetic variance in processing speed drives variation in aging of spatial and memory abilities.
Finkel D, Reynolds CA, McArdle JJ, Hamagami F, Pedersen NL
Dev Psychol 2009 May;45(3):820-34

Quantitative genetic analysis of latent growth curve models of cognitive abilities in adulthood.
Reynolds CA, Finkel D, McArdle JJ, Gatz M, Berg S, Pedersen NL
Dev Psychol 2005 Jan;41(1):3-16

Longitudinal memory performance during normal aging: twin association models of APOE and other Alzheimer candidate genes.
Reynolds CA, Prince JA, Feuk L, Brookes AJ, Gatz M, Pedersen NL
Behav. Genet. 2006 Mar;36(2):185-94

Preventive cardiology. The time has come for physicians to get involved.
Nash DT
Postgrad Med 1988 Jul;84(1):231-4

Genetic variance in processing speed drives variation in aging of spatial and memory abilities.
Finkel D, Reynolds CA, McArdle JJ, Hamagami F, Pedersen NL
Dev Psychol 2009 May;45(3):820-34

Both odor identification and ApoE-ε4 contribute to normative cognitive aging.
Finkel D, Reynolds CA, Larsson M, Gatz M, Pedersen NL
Psychol Aging 2011 Dec;26(4):872-83

Genotype-environment interactions: cognitive aging and social factors.
Reynolds CA, Gatz M, Berg S, Pedersen NL
Twin Res Hum Genet 2007 Apr;10(2):241-54
Brightness contrast, brightness constancy, and the ratio principle.
Heinemann EG
Percept Psychophys 1989 Jan;45(1):89-91

Association between CYP2C19 polymorphism and depressive symptoms.
Sim SC, Nordin L, Andersson TM, Virding S, Olsson M, Pedersen NL, et al
Am. J. Med. Genet. B Neuropsychiatr. Genet. 2010 Sep;153B(6):1160-6

Genetic and environmental mediation of the associations between self-rated health and cognitive abilities.
Svedberg P, Gatz M, Pedersen NL
Exp Aging Res ;35(2):178-201


Content reviewer: