Kenneth S Kendler1,2, Henrik Ohlsson3, Jan Sundquist3,4, Kristina Sundquist3,4. 1. Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, VA, USA. 2. Department of Psychiatry, Virginia Commonwealth University, Richmond, VA, USA. 3. Center for Primary Health Care Research, Lund University, Malmö, Sweden. 4. Department of Family Medicine and Community Health, Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, USA.
Abstract
BACKGROUND: Although alcohol use disorder (AUD) runs strongly within families, studies examining the impact of rearing environment, unconfounded by genetic effects, are rare and, to date, contradictory. We here seek to conduct such a study using an adoptive co-sib control design. METHODS: Defining high-risk as having ⩾1 biological parent with an externalizing syndrome (AUD, drug abuse or crime), we identified 1316 high-risk full-sibships and 4623 high-risk half-sibships containing at least one member who was home-reared and one who was adopted-away. Adoptive families are carefully screened in Sweden to provide high-quality rearing environment for adoptees. AUD was assessed from national medical, criminal and pharmacy registries. RESULTS: Controlling for sex, parental age at birth, and, for half-siblings, affection status of the non-shared parent, hazard ratios (±95% CI) for AUD in the matched adopted v. home-reared full- and half-siblings were, respectively, 0.76 (0.65-0.89) and 0.77 (0.70-0.84). The protective effect of adoption on AUD risk was stronger in the full- and half-sibling pairs with very high familial liability (two high-risk parents) and significantly weaker when the adoptive family was broken by death or divorce or contained a high-risk adoptive parent. CONCLUSIONS: In both full- and half-sibling pairs, we found evidence that the rearing environment substantially impacts on the risk for AUD. High-quality rearing environments can meaningfully reduce the risk for AUD, especially in those at high familial risk.
BACKGROUND: Although alcohol use disorder (AUD) runs strongly within families, studies examining the impact of rearing environment, unconfounded by genetic effects, are rare and, to date, contradictory. We here seek to conduct such a study using an adoptive co-sib control design. METHODS: Defining high-risk as having ⩾1 biological parent with an externalizing syndrome (AUD, drug abuse or crime), we identified 1316 high-risk full-sibships and 4623 high-risk half-sibships containing at least one member who was home-reared and one who was adopted-away. Adoptive families are carefully screened in Sweden to provide high-quality rearing environment for adoptees. AUD was assessed from national medical, criminal and pharmacy registries. RESULTS: Controlling for sex, parental age at birth, and, for half-siblings, affection status of the non-shared parent, hazard ratios (±95% CI) for AUD in the matched adopted v. home-reared full- and half-siblings were, respectively, 0.76 (0.65-0.89) and 0.77 (0.70-0.84). The protective effect of adoption on AUD risk was stronger in the full- and half-sibling pairs with very high familial liability (two high-risk parents) and significantly weaker when the adoptive family was broken by death or divorce or contained a high-risk adoptive parent. CONCLUSIONS: In both full- and half-sibling pairs, we found evidence that the rearing environment substantially impacts on the risk for AUD. High-quality rearing environments can meaningfully reduce the risk for AUD, especially in those at high familial risk.
Authors: Kenneth S Kendler; Eric Turkheimer; Henrik Ohlsson; Jan Sundquist; Kristina Sundquist Journal: Proc Natl Acad Sci U S A Date: 2015-03-23 Impact factor: 11.205
Authors: Kenneth S Kendler; Hermine H Maes; Kristina Sundquist; Henrik Ohlsson; Jan Sundquist Journal: Am J Psychiatry Date: 2014-02 Impact factor: 18.112
Authors: C E Cutrona; R J Cadoret; J A Suhr; C C Richards; E Troughton; K Schutte; G Woodworth Journal: Compr Psychiatry Date: 1994 May-Jun Impact factor: 3.735