Gay and bisexual men had a statistically significant decrease in medical visits, mental health care visits, and mental health care costs in the 12 months following legalization of same-sex marriage in Massachusetts.

The finding was true for both partnered and nonpartnered men, according to a report in the December 15, 2011, American Journal of Public Health.

The researchers, at Columbia University, the Fenway Institute, and the Center for Population Research in LGBT Health in Boston, said the findings suggest that social policies can have an effect on health even when they are not directly related to health.

“We’ve known for many years that marriage is good for health and longevity, particularly for heterosexual men,” lead author Mark Hatzenbuehler, Ph.D., the Robert Wood Johnson Foundation Health and Society Scholar at Columbia University, told Psychiatric News. “This paper extends those results by showing that same-sex marriage may be effective in reducing health care use and costs among gay men as well, perhaps through reducing stress-related health problems.”

In 2002, all clinic patients at a large community-based health clinic serving sexual minorities in Boston were offered the chance to complete a survey asking for standard socioeconomic data as well as sexual orientation. A total of 1,309 patients completed the survey; these patients’ responses were linked to their outpatient billing records for medical and mental health visits. The researchers then extracted data for the 12 months before and after the Massachusetts Supreme Court legalized same-sex marriage on November 18, 2003.

For the final sample of 1,211 men, researchers extracted data on four outcome variables: medical care visits; medical care costs; mental health care visits; and mental health care costs. Mental health care visits included individual and group psychotherapy.

In the 12 months after the legalization of same-sex marriage, sexual minority men had a statistically significant decrease in medical care visits, mental health care visits, and mental health care costs, compared with the 12 months before the law was enacted. Both medical care and mental health care visits decreased by 13 percent each; medical costs decreased nonsignificantly by 10 percent, and mental health care costs decreased significantly by 14 percent.

Specifically, visits for depressive disorders, anxiety disorders, and adjustment disorders decreased in the 12 months following legalization compared with the preceding 12 months, with associated reductions in cost.

Interestingly, these effects were not modified by partnership status, indicating that the marriage law’s health effects were similar for gay men both in and not in a relationship with a same-sex partner.

“I think this finding is surprising only if we view same-sex marriage policies as strictly about marriage and therefore only relevant to those gays and lesbians who want to get married, and not as part of a broader class of current policies that target LGBT individuals,” Hatzenbuehler told Psychiatric News.

“The field of psychiatry focuses largely on risk factors at the individual level—for example, genetics and cognitive styles,” Hatzenbuehler said. “These risk factors are important, but we also need to understand how social factors influence mental health at a population level.”

An abstract of “Effect of Same-Sex Marriage Laws on Health Care Use and Expenditures in Sexual Minority Men: A Quasi-Natural Experiment” is posted at http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.2011.300382.