Psychological Health Influences of Legal-Marriage and -Partnerships on Same-Sex Couples

This chapter explores whether Californians in same-sex legal marriages and partnerships reported lower levels of psychological distress than other adult Californians after the 2008 California Supreme Court Decision that legalized same-sex marriage. We pooled 10 years of California Health Interview Survey (CHIS) data and employ a T1-T2 design to approximate a time series design. Dependent variables include overall self-related health, psychological distress, and household income. Independent variables include sexual identity and same-sex spouse. Bi-variate analyses compared self-reported mental and physical health between the two periods. We found decreased reports of poorer health and increased reports of very good health among gay men and lesbian women with legal spouses. Psychological distress decreased for legally coupled gay men and lesbians while increased slightly among unpartnered lesbian women and gay men. Household income increased among coupled lesbian women and gay men and decreased among others. Our project demonstrated positive health influences for Californians with legal same-sex spouses. We recommend future research projects that explore whether and how same- and opposite-sex marriage benefits health, well-being, and prosperity, and for marital status survey questions that are inclusive of sexual and gender identities and elicit the sex/gender of a respondent ’ s spouse.


Introduction
The U.S. federal government continues to increase the collection of sexualorientation data in its surveys [1][2][3][4], recognizes the need to develop a model for LGBT health that integrates behavioral, environmental, and socioeconomic factors, and intends to develop a framework, "to improve the health and well-being of people, … enhancing prosperity in the community and for its residents and businesses" [5] Marriage is one social contract long associated with health, longevity, and prosperity for people in such relationships [6][7][8][9][10]. During the period that preceded local, state, and then national legalization of same-sex marriage in the U.S. [11], researchers analyzed secondary data and proposed that such legal recognition could ensure some of the health and financial benefits that opposite-sex married couples have long-enjoyed [9,12,13].
was an effort-using Likert scales from 0 representing none of the time, to 4 representing all the time. The K6 scale is summed with scores of 0 representing lowest, and 24 representing the highest psychological distress level. Dichotomized moderate mental distress is defined as the sum of K6 scores at or above 5, the optimal lower threshold indicative of moderate mental distress [13]. The K6 continuous measure and the dichotomized moderate mental distress scores have demonstrated reliability and validity in population datasets, including CHIS [26,27]. We used the dichotomous measure given our small subsample of married and partnered same-sex couples.

Sexual identity
CHIS participants self-reported as, "straight or heterosexual, as gay, lesbian or homosexual, bisexual, or other."

Legal marriage and partnership
CHIS asked all participants the standard marital question, "Are you now married, living with a partner in a marriage-like relationship, widowed, divorced, separated, or never married?" The response options do not include same-sex marriage or legal partnership. Previous research has shown that lesbian/gay women and gay men under-report marriage and legal partnership when responding to standard marital status questions [19]. To address under-report of marriage and to reflect the 2008 CSCD, CHIS asked all participants who reported having sex with someone of the same sex within the preceding 12 months whether that sexually-active respondent had a legal same-sex spouse or domestic partner. In addition to legallypartnered and married, we consolidated remaining status into other, a category including unmarried people who may be divorced, widowed, never-married, or living with a partner without legal recognition. We also constructed a binary variable for married/legally-partnered to increase the power of the data to find statistically significant results. There is no way to separate married and legally-partnered for data prior to 2009 because of questionnaire wording. In 2009, revised question wording distinguished married from legally-partnered. We compared percent of moderate psychological distress between married and legally-partnered lesbian women and gay men and found no statistical difference. Therefore, we collapsed married/legally-partnered as one group for our analyses in order to compare pre to post CSCD.

Statistical analyses
We performed all statistical analyses using CHIS data pooled from survey years 2005-2015 and weighted to the California population. Lesbian/gay women and gay men were compared to their heterosexual counterparts on sociodemographic variables. Data collected before 2008 were considered prior to the CSCD and data collected in 2008 and later were considered after the legal decision. The proportion of the sample experiencing moderate mental distress was plotted over time by gender, sexual identity, and couple status. Joinpoint analysis tested if trends in moderate psychological distress changed at specific years. Joinpoint uses weighted least squares to fit the trend model, using the inverse of the standard error as the weight variable.
Bi-variate and logistic regression analyses compared psychological distress using the K6 scale between the periods before and after the CSCD. Bi-variate analyses were replicated only for lesbian/gay women and gay men and compared stress levels between those legally married or partnered as compared with those not. Independent variables of the logistic regression included the main effects of sexual identity, marriage/legal partnership and the timing of CSCD (before or after) and all the two-way interaction effects (i.e., sexual identity x marriage/legal partnership, sexual identity x timing of CSCD, marriage/legal partnership x timing of CSCD) and the three-way interaction effect of the three variables (i.e., sexual identity x marriage/legal partnership x timing of CSCD) while adjusting for the following sociodemographics: Race, marital/partnered status, children in home, education, work status, income, geography, age. The conditional adjusted odds ratios compare the odds of reporting moderate mental health distress for that specific group pre-versus after-CSCD while holding all other variables constant.

Results
A total of 192,460 individuals were included in the analysis, with 6995 participants identifying as lesbian/gay women and gay men. Table 1 displays sociodemographics of lesbian, gay, and heterosexual individuals before and after the CSCD. There is an overall increase in non-white populations regardless of sexual orientation and a notable increase in reports of legal married/partnered lesbian women and gay men. Before 2008, only 11 percent of lesbian/gay female and gay male Californians reported being legally married/partnered. That percentage rose to 26.5% after the state Supreme Court decision. Among heterosexuals, marriage slightly declined, from 57.2% before the ruling versus 51.8% after the decision. Table 1 also reports the mean distress score for sexual identity group pre versus post CSCD and shows that lesbian women and gay men reported higher scores of moderate distress than their heterosexual counterparts. Table 2 provides descriptive results expressly for lesbian women and gay men by marital/partnered status pre versus post-CSCD. Employment was stable among married/partnered respondents, but unemployment increased among others. Household income increased among married/partnered respondents but decreased among others. Notably, the percentage of respondents who had a child in the home decreased from 51 to 36% among married/partnered lesbian and gay respondents. Mean scores of moderate mental distress decreased for married or legally partnered but increased for other following the CSCD.
We explored the relationship the 2008 CSCD on self-reported moderate psychological distress among legally married or partnered and other respondents by sexual identity. A higher percentage of Lesbian women and gay men reported rates of distress than heterosexual counterparts. There was no change in the proportion of lesbian women and gay men who experienced moderate mental psychological distress before and after the CSCD. However, this result changes when we compare those who are legally partnered or married compared to other relationship status Legally married or partnered lesbian women and gay men were half as likely to report moderate psychosocial distress after the CSCD [OR, 0.52] as compared to prior to the CSCD. In contrast, moderate psychological distress remained relatively unchanged among other lesbian women and gay men [1.04], married heterosexuals [0.94] and other heterosexuals [0.94]. These results and their 95% confidence intervals (CIs) for statistically significant relationships appear in Table 3.
We conducted Joinpoint analyses to determine if moderate psychological distress decreased at specific years.    Table 2.
Descriptive statistics for lesbian women and gay men by marital/partnered status.  separately (married/partnered gays, married partnered lesbians). Distress increased in this same year among other gay men and lesbian women. Distress scores increased from their 2013 levels among married/partnered lesbians and gays in 2014 and decreased only among gay men in 2015, the year of the U.S. Supreme Court decision that legalized same-sex marriage. However, none of these trends were significant as determined by the p-values for each slope in Joinpoint analyses. In addition, there was no significant changing point in terms of year for any of the slopes for moderate psychological distress for any of the sub-groups.

Discussion
Before same-sex marriage became legal throughout the United States in 2015, clinical researchers promoted marriage equality as a health promotion strategy for lesbian/gay women and gay men [8,12,28]. Others ventured that marriage equality not only would improve lesbian/gay health, but also would benefit society at large [29]. Though our project was more circumscribed, we found some confirmation of our exploratory aim: Many adult Californians in legal same-sex partnerships and marriages reported lower levels of psychological distress than their single counterparts following the CSCD.
The inelegant results in this quasi-natural experiment may be no surprise, as this time period was fraught with instability regarding the state legality of same-sex marriage/partnerships and the stay of issuing same-sex marriage licenses between November 2008 and June 2014. Though Californians in same-sex unions maintained their legal status at the ends of the disputes, during this tumultuous legal period some undoubtedly worried whether their marital status would continue. Engaged same-sex couples were precluded from marriage licenses. Those with same-sex orientations may have experienced stressors related to passage of the state referendum Proposition 8 and the court cases appealing that referendum that abolished marriage for same-sex couples. In sum, this period was uncertain on the status of same-sex marriage and mental health self-reports fluctuated during periods when the issue's status also changed (Figure 1, Table 3). Reports of distress declined over time for legally-married or -partnered lesbian women and gay men while distress increased for their single counterparts. However, the changes in slope were not significant and no single year showed as the changing point when using Joinpoint analyses. In contrast, distress reports among heterosexual women and men remained relatively stable between 2009 and 2015. Our results suggest that marriage may have had a positive influence on mental health for legally-married and -partnered gay and lesbian people even during this turbulent period.
Recent studies posit that people in legal same-sex relationships have higher relationship stability, more financial resources, and better health outcomes than couples who cohabit without legal recognition [19,30] and that marriage may mitigate minority stress effects among same-sex and other marginalized couples [21]. Our project found lower psychological distress levels among many lesbian/gay women and gay male Californians, though this health benefit was not uniform over time across same-sex marriages or legal partnerships-perhaps a reflection of the time period during which the continued legality of same-sex marriage in California was uncertain. The support we found for our hypothesis, even when the data were collected during a period in which the legality of same-sex marriage was questioned, reinforces a finding of a National Academies report that encourages research to understand the qualities of resilience unique to sexual minorities and how that relates to their overall health [3].
We also found evidence that gay and lesbian CHIS respondents who were legally-married and -partnered were substantively more likely to be employed and to have college educations than those unmarried or not legally partnered. That said, marriage equality in California can find its roots in 2005 legislation that required private employers to extend health insurance benefits to employees' same-sex partners just as the benefits were extended to opposite-sex spouses-a time when samesex marriage was unlawful. An earlier study found this policy had no influence on gay men but was of great benefit to lesbian women [17]. Our work, in light of previous studies, suggests more research is needed to explore whether and how same-and opposite-sex marriage is associated with benefits to health, well-being, and prosperity across communities.
Minority stress theory posits that prejudicial experiences over the lifecourse have a negative impact on the actual and perceived mental and physical health of lesbian/gay people [18,21,31]. Full legal protections for sexual-and genderminorities are incomplete; however, an exploration of the influence of national marriage equality on health issues of the multifaceted, non-exclusively-heterosexual, cis-and transgender people who comprise sexual minorities may be worthwhile.
Studies using future iterations of CHIS can determine whether the mental health benefits we found continue over time and whether other self-reported health benefits emerge. For example, extant research suggests that marriage equality has, at minimum, mental health benefits for non-heterosexual youth for whom suicide is the second most frequent cause of death [32][33][34].
Additional research projects might explore these questions across U.S. populations beyond California. To explore the implications of minority stress theory more thoroughly, future projects might consider biopsychosocial measures typically associated with stress responses-for example, to explore changes or differences in telomere lengths [35] and/or cortisol levels [36] in addition to self-reported data from single and married lesbian/gay women, gay men, and additional sexual and gender minorities over time. Longitudinal studies in this regard would enhance both understanding and health promotion among sexual minorities.

Limitations
First, as CHIS is a continuous cross-sectional study, our findings suggest a trend in the populace rather than a change in a discrete set of Californians. Second is that legal partnerships and legal marriage did not convey identical rights and privileges between 2005 and 2008, a period that included concurrent, limited periods of cityand county-based same-sex marriages in California. Moreover, litigation precluded issuance of marriage licenses to same-sex couples between November 2008 and June 2013. Disparate results among legally-partnered, married, and other gay male and lesbian Californians perhaps reflect that uncertainty. Third, we were unable to report results separately by legal same-sex marriage and partnership between 2013 and 2015 though our results nonetheless appear to correspond with the historical events related to this issue during the period. Fourth is the need to exclude bisexually-identified Californians because the survey's order and skip pattern complicate notions of selfidentification and self-report of sexual behavior. For example, a bisexually-identified respondent who reported no sex with a same-sex partner in the last 12 months would not have been asked the question of same-sex legal partnership/marriage. Additionally, the partner's sex/gender and sexual orientation were not reported.
This fourth limitation demonstrates that a respondent's reported sexual identity is not necessarily equivalent to that respondent's sexual behavior or to the sex/ gender of that individual's spouse-particularly in our era of increasingly fluid sexual and gender identities [37][38][39] and growing researcher attention to the intersectionality framework to integrate the complexity of individual lived experiences within efforts to improve care and research in health and well-being [40][41][42]. For a more comprehensive understanding of the influences of sexual identity, gender identity, and marital status on human health and well-being, survey questions may elicit not only the sex/gender identity of a respondent but also of the respondent's spouse, for example, to help determine the influence of same-or opposite-sex marriage on the health of bisexual or transgender people.
Researchers adapting CHIS to account more precisely for same-sex marriage influences could follow the current question on "now married, living with a partner in a marriage-like relationship, widowed, divorced, separated, or never married" [43] by asking whether the spouse/partner referenced in the previous question is the same or opposite sex as the respondent.
There are thorough conversations across and outside the academy that will lead to comprehensive revisions of survey methodologies to measure the identity and behavior of respondents and their respective spouses. In the interim, the California Health Interview Survey (CHIS) provides a best practice on how to design and adapt questions to collect data that can explain the influence of legal marriage and partnerships on health and well-being, including sex/gender and sexual orientation identities [1]. Research and surveillance methodologies occasionally must respond quickly to provide data-driven public health recommendations. This study demonstrates CHIS's ability to explore the health impact of marriage for same-sex couples, and a need for survey questions to elicit information about marital status and the sex/gender of a respondent's spouse inclusive of sexual identities. Such collection is critical for data-driven health recommendations as sexual and gender identities become increasingly fluid and nuanced.
Behavioral and Social Sciences Research (OBSSR), the NIH Office of Research on Women's Health (ORWH), and the National Cancer Institute (NCI) provided financial support for the design and implementation of previous iterations of CHIS. OBSSR and NCI supported access to the dataset created and analyzed for this project.

Author Disclosure Statement
No competing financial interests exist.

Disclaimer
This article represents only the authors' views and perspectives, not the positions of the National Institutes of Health or the U.S. Government.