ABSTRACT

We aimed to test whether the association between same-sex marriage and common mental health diagnoses was explained by shared genetic and environmental familial influences using sibling comparison and adoption analyses. For the sibling comparison analysis, participants (1,177,712 men and 1,266,917 women) were individuals born in Sweden between 1932 and 1994 and had ever been recorded as married (in opposite-sex or same-sex marriages). For the adoption analysis, participants were 147,164 and 1,298 female–female full sibling and adoptive sibling pairs, respectively. Based on medical records, prescribed medication, and death certificates, depression, substance abuse, and suicide (completed and attempted) from age 18 years were identified. For both sexes, being in a same-sex marriage was associated with greater risk of depression, substance abuse, and suicide, compared with being in an opposite-sex marriage. Controlling for shared familial confounding reduced this difference by less than 20% in magnitude, but overall mental health disparities for individuals in same-sex marriages remained statistically significant. Among women, only the genetic correlation between same-sex marriage and depression was statistically significant (r = .33). Same-sex marriage, as a proxy for sexual orientation, was associated with increased risk of certain mental health diagnoses and shared familial confounding explained a small component of this association, depending on the diagnosis. The findings indicate that sexual orientation disparities in mental health outcomes may involve unmeasured factors, and a relatively small proportion should be considered that may be due to shared familial confounding relevant to both sexual orientation and psychopathology.

摘要

我们的目的是通过兄弟姐妹比较和收养分析来测试同性婚姻与常见心理健康诊断之间的关联是否可以通过共同的遗传和环境家庭影响来解释。对于兄弟姐妹比较分析，参与者（1,177,712 名男性和 1,266,917 名女性）是 1932 年至 1994 年间出生于瑞典且曾被记录为已婚者（异性或同性婚姻）的个体。对于收养分析，参与者分别为 147,164 名女性同性兄弟姐妹和 1,298 名收养兄弟姐妹。根据医疗记录、处方药物和死亡证明，确定了 18 岁起的抑郁症、药物滥用和自杀（已完成和未遂）。对于男女来说，同性婚姻都会增加患抑郁症、药物滥用、与异性婚姻相比，自杀率更高。控制共同的家庭混杂因素后，这种差异的幅度减少了不到 20%，但同性婚姻中个人的总体心理健康差异仍然具有统计学意义。在女性中，只有同性婚姻与抑郁症之间的遗传相关性具有统计显着性（r = .33)。同性婚姻作为性取向的代表，与某些心理健康诊断的风险增加有关，而共同的家庭混杂因素解释了这种关联的一小部分，具体取决于诊断。研究结果表明，心理健康结果中的性取向差异可能涉及未测量的因素，并且应考虑相对较小的比例，这可能是由于与性取向和精神病理学相关的共同家庭混杂因素造成的。