Unmarried status in Asian population tied to higher mortality risk: JAMA

JAPAN: Among the Asian population, unmarried individuals are at higher risk of mortality than their married counterparts, reported a cohort study published in JAMA Network Open. Mortality risk was found to be total and cause-specific.

Overall, the trend shows a global decline in the marriage rate over the last decades. A recent survey reported that 50.3 Percent Population of India has never married. A burgeoning literature suggests that marriage may have a wide range of benefits including mental and physical health. Although there is a difference in the pattern of marriage among societies, studies have reported the link between marriage and mortality in non-Western populations. Though previous studies of Asian cohorts have published inconsistent results, researchers hypothesized that being married may be associated with survival benefits in Asian populations.

Researchers thus conducted a cohort study using individual-level data from the Asia Cohort Consortium (ACC), with more than 1 million participants, to ascertain the association between marital status and cause-specific mortality. Study-specific hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards model and then pooled using a random-effects meta-analysis (February 2021- August 2021)

Of 623 140 participants (326 397 women [52.4%] and 296 743 men [47.6%]; mean age, 53.7 years; mean follow-up time, 15.5 years), 123 264 deaths were ascertained.

Analysis shows that: 

• Compared with married individuals, those who were unmarried had pooled HRs of 1.15 for total mortality.

• Positive associations with total mortality were also observed for those who were single, separated, divorced, and widowed (HR-1.62,1.35,1.38 and 1.09 respectively)

• In subgroup analyses, the positive association persisted across baseline health conditions, and the risk of death was more pronounced among men or people younger than 65 years.

• Marital status was associated with higher mortality among men compared to women

The strength of this pooled analysis is the prospective design of each study, which minimized potential recall bias and selection bias. Also, this being the largest pooled analysis of Asian populations so far, it allowed researchers to provide estimates with sufficient precision and to examine reverse causation.

Based on the study analysis authors reported that unmarried individuals had a 15% increased risk of total mortality compared to married people. The association persisted across baseline health conditions and was particularly evident in men and individuals who were younger than 65 years at baseline.

The authors conclude with the note that the study findings underscore the potential to reduce unfavorable mortality outcomes among unmarried individuals in Asia.

Reference:

Leung CY, Huang H, Abe SK, et al. Association of Marital Status With Total and Cause-Specific Mortality in Asia. JAMA Netw Open. 2022;5(5):e2214181. doi:10.1001/jamanetworkopen.2022.14181