School of Psychology, University of Queensland, Brisbane, Queensland, Australia.
Psychol Med. 2012 Mar;42(3):521-32. doi: 10.1017/S0033291711001577. Epub 2011 Aug 26.
Gays, lesbians and bisexuals (i.e. non-heterosexuals) have been found to be at much greater risk for many psychiatric symptoms and disorders, including depression. This may be due in part to prejudice and discrimination experienced by non-heterosexuals, but studies controlling for minority stress, or performed in very socially liberal countries, suggest that other mechanisms must also play a role. Here we test the viability of common cause (shared genetic or environmental etiology) explanations of elevated depression rates in non-heterosexuals.
A community-based sample of adult twins (n=9884 individuals) completed surveys investigating the genetics of psychiatric disorder, and were also asked about their sexual orientation. Large subsets of the sample were asked about adverse childhood experiences such as sexual abuse, physical abuse and risky family environment, and also about number of older brothers, paternal and maternal age, and number of close friends. Data were analyzed using the classical twin design.
Non-heterosexual males and females had higher rates of lifetime depression than their heterosexual counterparts. Genetic factors accounted for 31% and 44% of variation in sexual orientation and depression respectively. Bivariate analysis revealed that genetic factors accounted for a majority (60%) of the correlation between sexual orientation and depression. In addition, childhood sexual abuse and risky family environment were significant predictors of both sexual orientation and depression, further contributing to their correlation.
Non-heterosexual men and women had elevated rates of lifetime depression, partly due to shared etiological factors, although causality cannot be definitively resolved.
同性恋、双性恋者（即非异性恋者）被发现面临许多精神症状和障碍的风险更高，包括抑郁症。这可能部分归因于非异性恋者所经历的偏见和歧视，但控制了少数群体压力的研究，或在非常社会自由的国家进行的研究表明，其他机制也必须发挥作用。在这里，我们测试了共同原因（共同的遗传或环境病因）解释非异性恋者抑郁率升高的可行性。
一项基于社区的成年双胞胎样本（n=9884 人）完成了调查精神障碍遗传学的调查，并被问及他们的性取向。样本的大部分被问及不良的童年经历，如性虐待、身体虐待和危险的家庭环境，以及年长兄弟的数量、父母的年龄和亲密朋友的数量。使用经典双胞胎设计分析数据。
非异性恋男性和女性的终生抑郁症发病率高于异性恋者。遗传因素分别解释了性取向和抑郁的 31%和 44%的变异。双变量分析显示，遗传因素解释了性取向和抑郁之间相关性的大部分（60%）。此外，儿童期性虐待和危险的家庭环境是性取向和抑郁的重要预测因素，进一步促成了它们的相关性。
非异性恋男性和女性的终生抑郁症发病率较高，部分原因是共同的病因因素，但因果关系不能明确确定。
