Department of Society, Human Development, and Health, School of Public Health, Harvard University, Kresge Building, 677 Huntington Ave., Boston, MA, 02115, USA.
Arch Sex Behav. 2013 Feb;42(2):161-71. doi: 10.1007/s10508-012-0021-9. Epub 2012 Sep 14.
Epidemiological studies find a positive association between physical and sexual abuse, neglect, and witnessing violence in childhood and same-sex sexuality in adulthood, but studies directly assessing the association between these diverse types of maltreatment and sexuality cannot disentangle the causal direction because the sequencing of maltreatment and emerging sexuality is difficult to ascertain. Nascent same-sex orientation may increase risk of maltreatment; alternatively, maltreatment may shape sexual orientation. Our study used instrumental variable models based on family characteristics that predict maltreatment but are not plausibly influenced by sexual orientation (e.g., having a stepparent) as natural experiments to investigate whether maltreatment might increase the likelihood of same-sex sexuality in a nationally representative sample (n = 34,653). In instrumental variable models, history of sexual abuse predicted increased prevalence of same-sex attraction by 2.0 percentage points [95 % confidence interval (CI) = 1.4-2.5], any same-sex partners by 1.4 percentage points (95 % CI = 1.0-1.9), and same-sex identity by 0.7 percentage points (95 % CI = 0.4-0.9). Effects of sexual abuse on men's sexual orientation were substantially larger than on women's. Effects of non-sexual maltreatment were significant only for men and women's sexual identity and women's same-sex partners. While point estimates suggest much of the association between maltreatment and sexual orientation may be due to the effects of maltreatment on sexual orientation, confidence intervals were wide. Our results suggest that causal relationships driving the association between sexual orientation and childhood abuse may be bidirectional, may differ by type of abuse, and may differ by sex. Better understanding of this potentially complex causal structure is critical to developing targeted strategies to reduce sexual orientation disparities in exposure to abuse.
流行病学研究发现，儿童期身体和性虐待、忽视以及目睹暴力与成年后同性性行为之间存在正相关关系，但直接评估这些不同类型的虐待与性行为之间关联的研究无法理清因果关系，因为虐待和新出现的性行为的顺序难以确定。新生的同性取向可能会增加受虐待的风险；或者，虐待可能会影响性取向。我们的研究使用基于家庭特征的工具变量模型，这些特征可以预测虐待，但不太可能受到性取向的影响（例如，有继父或继母），以此作为自然实验，来调查在一个具有全国代表性的样本（n=34653）中，虐待是否会增加同性性行为的可能性。在工具变量模型中，性虐待史预测同性吸引力的流行率增加了 2.0 个百分点[95%置信区间（CI）=1.4-2.5]，同性伴侣增加了 1.4 个百分点（95%CI=1.0-1.9），同性身份增加了 0.7 个百分点（95%CI=0.4-0.9）。性虐待对男性性取向的影响明显大于对女性的影响。非性虐待的影响仅对男性和女性的性身份以及女性的同性伴侣有显著影响。虽然点估计表明，虐待与性取向之间的关联可能在很大程度上归因于虐待对性取向的影响，但置信区间很宽。我们的研究结果表明，驱动性取向与儿童期虐待之间关联的因果关系可能是双向的，可能因虐待类型而异，也可能因性别而异。更好地理解这种潜在的复杂因果结构对于制定有针对性的策略来减少性取向差异和暴露于虐待的情况至关重要。
