Examining cultural background and the protective effect of marriage on alcohol use disorder in Sweden

Jessica E Salvatore; Sara Larsson Lönn; Karen G Chartier; Jan Sundquist; Kenneth S Kendler; Kristina Sundquist

doi:10.1177/00207640241288211

Examining cultural background and the protective effect of marriage on alcohol use disorder in Sweden

Int J Soc Psychiatry. 2024 Oct 22:207640241288211. doi: 10.1177/00207640241288211. Online ahead of print.

Authors

Jessica E Salvatore¹, Sara Larsson Lönn², Karen G Chartier^{3

4}, Jan Sundquist², Kenneth S Kendler^{4

5

6}, Kristina Sundquist²

Affiliations

¹ Department of Psychiatry, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.
² Center for Primary Health Care Research, Lund University, Malmo, Sweden.
³ School of Social Work, Virginia Commonwealth University, Richmond, USA.
⁴ Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, USA.
⁵ Department of Psychiatry, Virginia Commonwealth University, Richmond, USA.
⁶ Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, USA.

PMID: 39435759
DOI: 10.1177/00207640241288211

Abstract

Background: Little is known about whether the protective effect of marriage on alcohol use disorder (AUD) varies by cultural background.

Aims: Using Swedish national data, we examined whether marriage is associated with a stronger reduction in AUD risk among Swedes of a Swedish background (i.e. those with two Swedish-born parents) compared to Swedes with a foreign background (i.e. one or two foreign-born parents) and whether the protective effect of marriage depends on whether the spouse has a Swedish or foreign background.

Method: Among those born in Sweden 1960 to 1990 (3,093,439; 49% female), associations between cultural background and AUD registration during marriage were estimated with Cox models. Analyses of intra- and intermarriage on AUD registration were examined with Cox models and limited to groups of focal individuals for which there was sufficient statistical power, which included Swedes with two Swedish-born parents, two Finnish-born parents, or bicultural background (one Swedish and one foreign-born parent). Models were sex stratified.

Results: Marriage was associated with reductions in AUD risk among those with Swedish and with foreign backgrounds, though less protective for males of Finnish versus Swedish background as indicated by a significant interaction between marital status and parental region of birth, HR = 0.80, 95% CI [0.71, 0.90]. Marriage was also less protective for those with a bicultural versus Swedish background, HR_males = 0.87, 95% CI [0.81, 0.92] and HR_females = 0.88, 95% CI [0.81, 0.97]. Among those of Swedish background, marriage to a spouse with a foreign versus Swedish background was associated with increased risk of AUD, HR_males = 1.26, 95% CI [1.19, 1.34] and HR_females = 1.20, 95% CI [1.10, 1.31]. This risk was diminished when family-level confounders (genes, rearing environment) were controlled for.

Conclusions: The protective effect of marriage depends on cultural background, with some evidence that increased risks associated with a spouse's foreign background are confounded by family-level factors.

Keywords: Marriage; alcohol use disorder; cultural background.