title: Persistent leisure-time physical activity in adulthood and use of antidepressants: A follow-up study among twins.
abstract: To study whether persistent leisure-time physical activity (PA) during adulthood predicts use of antidepressants later in life.
  
  
  
  The Finnish Twin Cohort comprises same-sex twin pairs born before 1958, of whom 11 325 individuals answered PA questions in 1975, 1981 and 1990 at a mean age of 44 years (range 33-60). PA volume over 15-years was used as the predictor of subsequent use of antidepressants. Antidepressant use (measured as number of purchases) for 1995-2004 were collected from the Finnish Social Insurance Institution (KELA) prescription register. Conditional logistic regression was conducted to calculate odds ratios (OR) with 95% confidence intervals (CI) for the use of antidepressants in pairs discordant for PA (642, including 164 monozygotic (MZ) pairs).
  
  
  
  Altogether 229 persons had used at least one prescribed antidepressant during the study period. Active co-twins had a lower risk (unadjusted OR 0.80, 95%CI 0.67-0.95) for using any amount of antidepressants than their inactive co-twins; trends being similar for DZ (0.80, 0.67-0.97) and MZ pairs (0.78, 0.51-1.17). The lowest odds ratio (0.51, 0.26-0.98) was seen among MZ pairs after adjusting for BMI, smoking and binge drinking. The point estimates were similar but non-significant for long-term antidepressant use (4+purchases equivalent to 12 months use).
  
  
  
  Self-reported physical activity and low number of discordant MZ pairs.
  
  
  
  Use of antidepressants was less common among physically active co-twins even when shared childhood experiences and genetic background were controlled for. Physical activity in midlife may therefore be important in preventing mild depression later in life.
authors.affiliation: Department of Health Sciences, University of Jyväskylä, Finland. Electronic address: katja.waller@jyu.fi.
authors.forename: K
authors.initials: K
authors.lastname: Waller
authors.affiliation: Department of Public Health, University of Helsinki, Finland; Mental Health Unit, Department of Health, National Institute for Health and Welfare, Finland; Institute for Molecular Medicine FIMM, University of Helsinki, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Kaprio
authors.affiliation: Department of Public Health, University of Helsinki, Finland; Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Korhonen
authors.affiliation: Department of Behavioral Sciences, University of Helsinki, Finland; The Social Insurance Institution, Kela, Helsinki, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Tuulio-Henriksson
authors.affiliation: Department of Health Sciences, University of Jyväskylä, Finland.
authors.forename: U M
authors.initials: UM
authors.lastname: Kujala
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use*; D003866:Depressive Disorder / Q000188:drug therapy* / Q000523:psychology; D015444:Exercise / Q000523:psychology*; D005260:Female; D005387:Finland; D005500:Follow-Up Studies; D006801:Humans; D007899:Leisure Activities / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D012306:Risk; D014427:Twins / Q000523:psychology*
chemical_list: D000928:Antidepressive Agents
keywords: Antidepressants; Depression; Follow-up; Genetic; Inactivity; Physical activity; Twins