Date: June 23, 2020
Thanks to Flashraid99!
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.
Epidemiological studies find a positive association between childhood maltreatment and same-sex sexuality in adulthood, with lesbians and gay men reporting 1.6 to 4 times greater prevalence of sexual and physical abuse than heterosexuals (Corliss, Cochran, & Mays, 2002; Hughes, Haas, Razzano, Cassidy, & Matthews, 2000; Roberts, Austin, Corliss, Vandermorris, & Koenen, 2010; Saewyc et al., 2006). Four explanations have been proposed for this association. The first is that nascent same-sex sexuality causes childhood maltreatment, through two pathways: (1) adolescents who reveal their same-sex sexual orientation are targeted for maltreatment (D’Augelli & Grossman, 2001; Saewyc et al., 2006); and (2) adolescents exploring same-sex attractions may put themselves in risky situations, increasing likelihood of maltreatment (Corliss et al., 2002; Holmes & Slap, 1998). A second explanation proposes that sexual orientation minorities disproportionately exhibit gender-nonconforming behaviors in childhood (Rieger, Linsenmeier, Gygax, & Bailey, 2008; Roberts, Rosario, Corliss, Koenen, & Austin, 2012) and are targeted for maltreatment (Alanko et al., 2010).
A third explanation is that reported differences are attributable to differential recall of maltreatment by sexual orientation, due either to self-reflection during the coming out process or to differential willingness to endorse stigmatizing experiences (Corliss et al., 2002). A fourth explanation is that maltreatment increases likelihood of same-sex sexuality. Four pathways have been hypothesized: (1) maltreatment may cause loss of self-worth and create a stigmatized identity in victims; therefore, maltreated persons with same-sex preferences may be more willing to adopt another stigmatized identity, namely minority sexual orientation (Saewyc et al., 2006);(2) sexual abuse, perpetrated primarily by men, causes boys to believe they are homosexual (Gartner, 1999); (3) sexual abuse of girls by male perpetrators causes victims to be aversive to sexual relationships with men (Marvasti & Dripchak, 2004); and (4) sexual abuse of boys by men “teaches” homosexuality (Cameron & Cameron, 1995, 1996) (see also LeVay, 1996).
Interpretation of the association between exposure to maltreatment and sexual orientation is politically sensitive. Maltreatment is associated with many adverse health outcomes (Chermack, Stoltenberg, Fuller, & Blow, 2000; Riley, Wright, Jun, Hibert, & Rich-Edwards, 2010; Wegman & Stetler, 2009); thus, if maltreatment increases likelihood of same-sex sexual orientation, this finding may stigmatize same-sex sexual orientation by association. Furthermore, belief that sexual orientation is mutable rather than fixed has led to potentially traumatizing attempts to “cure” homosexuality, although belief that sexual orientation is biologically determined before birth has also led to attempts to “cure” homosexuality (LeVay, 1996). Despite possible political uses or misuses of scientific results, understanding the causal structure behind higher prevalence of maltreatment in sexual orientation minorities is important so that effective interventions can be designed to prevent maltreatment and to ameliorate possible sexual orientation disparities in maltreatment-related health outcomes (Institute of Medicine, 2011).
The causal structure driving the association between maltreatment and same-sex sexuality could be studied prospectively through repeated measures of maltreatment, gender nonconformity, and emerging sexual orientation during childhood. However, for ethical reasons, when childhood maltreatment is assessed in participants under age 18, mandated reporting requirements apply. Thus, in most prospective studies of children, maltreatment is assessed retrospectively in adulthood (Fergusson, Horwood, Ridder, & Beautrais, 2005). In cross-sectional studies of adults, age at which gender nonconforming behaviors appeared may be hard to recollect, and current sexual orientation may bias recollections of nonconformity. Thus, ascertaining the chronology of nonconformity, maltreatment, and emerging sexual orientation is challenging. Conventional statistical techniques directly assessing the association between maltreatment and same-sex sexual orientation cannot distinguish whether emergent same-sex sexual orientation leads to maltreatment or whether maltreatment leads to same-sex sexual orientation, or whether a third unmeasured variable is a common cause of both maltreatment and same-sex sexual orientation. However, instrumental variable analysis can provide statistically consistent estimates of the effect of an exposure on an outcome even when bidirectional causation or unmeasured common causes of the exposure and outcome may exist (Angrist & Krueger, 2001; Greenland, 2000).
In this study, we present instrumental variable analyses that use natural experiments involving factors that increase risk of childhood maltreatment but are not known to be influenced by or to directly influence nascent sexual orientation (Angrist, Imbens, & Rubin, 1996). Several family characteristics, namely, presence of a stepparent, poverty, parental alcohol abuse, and parental mental illness, are established risk factors for maltreatment (Administration on Children Youth and Families, 2007; Bays, 1990; Ronan, Canoy, & Burke, 2009) but are not plausibly affected by a child’s nascent sexual orientation. We therefore used these family characteristics as instrumental variables to estimate the effect of maltreatment on sexual orientation. Because instrumental variables analyses, to our knowledge, have not been used in sexuality research, we describe the approach here and contrast the assumptions under which our analysis or a conventional analysis could identify the effect of maltreatment on sexual orientation.
Numerous studies document an association between childhood physical and sexual abuse, neglect, and witnessing violence in childhood and same-sex sexuality. The present study used instrumental variable methods to analyze data from natural experiments to provide novel evidence that maltreatment may shape sexual orientation. Although no psychosocial determinants of sexual orientation have been demonstrated, studies using other samples have reported associations between same-sex sexuality and parental depression, parental substance use, and changes in caregivers during childhood, factors potentially associated with our instruments (Corliss, Austin, Roberts, & Molnar, 2009; Fergusson, Horwood, Ridder, & Beautrais, 2005). Furthermore, a recent large population-based twin study indicated that individual-specific environmental factors accounted for between 0.61 and 0.66 of the variance in same-sex sexual behavior in both sexes, a moderate to large effect of environment on same-sex sexuality (Langstrom, Rahman, Carlstrom, & Lichtenstein, 2010), raising the question of whether those environmental factors might include psychosocial influences.
Our results relied on the strong assumption that the instruments did not affect sexual orientation directly or through pathways other than abuse or maltreatment and that no omitted factors, including genes (Zietsch, Verweij, Bailey, Wright, & Martin, 2011), affected both the instruments and sexual orientation. Alternative explanations for the associations that we report should, therefore, focus on factors that influence both childhood family characteristics and sexual orientation. We consider this a fertile area for future empirical research. Such research is especially important because showing violations of the instrumental variable assumptions entails demonstrating other factors that determine sexual orientation. We are aware of one study that suggests there may be common genetic causes of same-sex sexual orientation and personality factors (Zietsch et al., 2011). The personality factors studied may increase risk for exposure to our instruments.
The associations of sexual orientation with our instruments were entirely attenuated in models including childhood maltreatment and sexual abuse. In other words, there was no elevated frequency of same-sex sexuality in persons with stepparents in early childhood, poverty, parental mental illness or alcohol abuse, except for children who were maltreated or abused. This would be unlikely to be the case were these factors associated with sexual orientation due to pleiotropic genetic effects, which would function irrespective of maltreatment status. Persons willing to identify as homosexual or bisexual may also be more willing to report parental alcohol abuse, mental illness, or poverty. We emphasize results using stepparent as an instrumental variable, because we expect that quality of retrospective reporting for this factor is likely to be the most reliable and reporting is unlikely to be affected by sexual orientation.
Our results suggest that from half to all of the increased prevalence of childhood sexual abuse experienced by sexual orientation minorities compared with heterosexuals may be due to the effects of sexual abuse on sexual orientation, possibly through previously proposed pathways: (1) abuse of boys perpetrated by men causes boys to believe they are gay; (2) abuse of girls by men leads them to be averse to sexual relationships with men; (3) abuse survivors may feel stigmatized and different from others and may, therefore, be more willing to behave in ways that are socially stigmatized, including acknowledging same-sex attraction or having same-sex partners (Saewyc et al., 2006). If this third pathway is a primary mechanism behind our findings, it follows that the true prevalence of same-sex sexuality is far higher than presently estimated by surveys: among participants with a high level of sexual abuse, 8.9% of men were gay or bisexual and 5.1% of women were lesbian or bisexual (versus, respectively, 1.3% and 1.0% among persons not abused). It would also follow that in societies where same-sex sexuality is more accepted and less stigmatized, prevalence of same-sex sexual orientation would be higher and sexual orientation disparities in abuse would be lower. This hypothesis could be tested by examining sexual orientation prevalence and abuse disparities across countries differing in acceptance of minority sexual orientation.
Other pathways may also link abuse and maltreatment with sexual orientation. Research in related fields suggests possible hormonal and behavioral mechanisms linking diverse types of maltreatment with sexuality. In animals, estrogen and related neuropeptides oxytocin and arginine vasopressin are involved in pair bonding, sexual behaviors, and the expression of gender-typical behavior, and may serve similar functions in humans (Cushing & Kramer, 2005; Lim & Young, 2006). Quality of parenting affects expression of estrogen, oxytocin, vasopressin, and their receptors in offspring, and has been hypothesized to affect later sexual behavior through epigenetic changes, particularly in the stria terminalis and the medial amygdala, brain regions that regulate social behavior (Cushing & Kramer, 2005). Thus, abuse and maltreatment may affect sexual orientation through biological mechanisms responsive to postnatal social environment.
Maltreatment, including sexual abuse, can have persistent effects on mood and behavior, which may increase likelihood of same-sex sexuality. Maltreatment causes emotional numbing, motivating survivors to seek stronger stimuli to experience positive states, leading to novelty-seeking and risk-taking behaviors (Fergusson & Horwood, 1998), which have been associated with same-sex sexuality (Fergusson, Horwood, Ridder, & Beautrais, 2005). Maltreatment also increases risk of substance abuse (Browne & Finkelhor, 1986), which may, in turn, increase likelihood of acting on same-sex attraction through disinhibition. Moreover, maltreatment leads to stress, depression, and anger (Briere & Elliott, 1994). The drive for intimacy and sex to repair depressed, stressed, or angry moods (Shrier, Shih, Hacker, & de Moor, 2007) may increase the likelihood of same-sex partners and attractions. Maltreatment also increases risk for borderline personality disorder, which has been associated with non-heterosexual orientation (Singh, McMain, & Zucker, 2011). To the extent these mechanisms exist, changes in social acceptance of minority sexual orientation will likely not affect differences in the prevalence of history of early childhood maltreatment by sexual orientation.
Maltreatment may also influence sex of partners and sexual orientation identity through housing insecurity, because young adults may sever connections to families subsequent to abuse. Poorly-housed youth may trade sex for housing, money or drugs (Greene, Ennett, & Ringwalt, 1999). For men especially, this sex work may involve same-sex sexual acts. Having had same-sex sexual contact, whether as victims of abuse or for compensation, people may be more likely to consider themselves bisexual or homosexual (Gartner, 1999). Our finding that sexual partners and identity were more strongly influenced by abuse for men than for women is in keeping with these hypothesized pathways. However, these pathways do not explain the strong estimated effect of sexual abuse on men’s attraction.
Prior research has indicated that women’s sexual orientation changes more across the lifespan than does men’s (Kinnish, Strassberg, & Turner, 2005; Ott, Corliss, Wypij, Rosario, & Austin, 2011), suggesting that women’s sexual orientation may be more readily influenced by environmental factors. Our findings do not support this hypothesis with regard to childhood abuse, although we know of no studies that compare male and female changes in sexual orientation in response to environmental exposures. Moreover, women and men in our sample were most likely exposed to sexual abuse that was qualitatively different. Because men are the principal perpetrators of sexual abuse of both boys and girls (Holmes & Slap, 1998; Vogeltanz et al., 1999), most men in our sample were likely exposed to same-sex abuse, while most women were likely exposed to opposite-sex abuse; thus, it is difficult to generalize from our findings to sex differences in response to environmental exposures more broadly.
Our results should be considered in the context of three further limitations. First, childhood measures were assessed retrospectively; therefore, recall error could attenuate estimates. A substantial minority of adults with court-documented abuse do not report abuse retrospectively (Williams, 1994). Second, because the NESARC questionnaire did not exclude unwanted encounters when asking about sexual partners, and because sexual abuse perpetrators are overwhelmingly male (Holmes & Slap, 1998), men may be referring to an abuser when they endorse same-sex partners. However, this limitation does not apply to results for same-sex attraction or identity or to any of the results for women. Third, the instrumented analyses estimated the effect of abuse and maltreatment among participants who were maltreated as a consequence of poverty, parental alcohol abuse, parental mental illness or having a stepparent. These estimates may not apply to people who were maltreated under other circumstances.
Our results suggest that the causal relationships driving the association between sexual orientation and abuse and maltreatment may be bidirectional, may differ by type of maltreatment, 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 maltreatment. Our findings indicated that sexual abuse may increase the likelihood of the three dimensions of same-sex sexuality for both sexes, and that non-sexual maltreatment may affect sexual orientation identity and women’s same-sex sexual partnering. While point estimates suggest that much of the association between maltreatment and sexual orientation may be due to the effects of maltreatment on sexual orientation, rather than the reverse, confidence intervals were wide. Results were, therefore, also consistent with approximately half the association between sexual abuse and minority sexual orientation being due to nascent sexual orientation leading to increased risk of maltreatment, and all or nearly all of the association between non-sexual maltreatment and sexual orientation being due to sexual orientation leading to maltreatment. Whether maltreatment influences sexuality or sexuality influences maltreatment, or both, public health interventions to increase tolerance and reduce assault and harassment of sexual orientation minorities are needed.”
Problem with the term “abuse” being related to anything, is that pretty much everything hinges on how broadly it is defined. They could “make a connection” to anything, including heterosexuality, if they wanted…It’s smoke and mirrors.
Of course…this study looks to be saying that abuse occurred more often for people who turned out to be homosexual, but they don’t know that the abuse influenced them in any way to be homosexual…Though, obviously, it still poses the question of whether “abuse” increases homosexuality.