Marital status and mortality among Japanese men and women: the Japan Collaborative Cohort Study
1 Department of Public Health Medicine, Doctoral Program in Social and Environmental Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba-shi, Ibaraki, Japan
2 Department of Social and Environmental Medicine, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita-shi, Osaka, Japan
3 Department of Public Health/Health Information Dynamics, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Japan
4 Department of Clinical Epidemiology, Institute of Industrial Ecological Science, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu-shi, Fukuoka, Japan
5 Department of Preventive Medicine, Graduate School of Medicine, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka-shi, Fukuoka, Japan
6 Department of Epidemiology and Environmental Health, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan
7 Department of Preventive Medicine/Biostatistics and Medical Decision Making, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Japan
BMC Public Health 2007, 7:73 doi:10.1186/1471-2458-7-73Published: 7 May 2007
Several studies have indicated a significant association between marital status and mortality risks. However, most of these studies have compared married and unmarried people without differentiating among single, divorced and widowed status. Moreover, gender differences in mortality rates associated with marital status have not been sufficiently clarified. With significant increases in the percentages of divorced and widowed people and a corresponding drop in the marriage rate in Japan during the past two or three decades, it can be expected that these changes will have a significant impact on mortality rates.
This investigation used a prospective study of a total of 94,062 Japanese men and women aged 40–79 who completed self-administered questionnaires at baseline and during a followed-up of 9.9-years.
Compared with married men, never-married men showed higher risks of mortality from cardiovascular disease [relative risk (RR) = 3.05, 95% confidence interval (CI) 2.03–4.60], respiratory disease (RR = 2.43, 95%CI 1.27–4.63), external causes (RR = 2.18, 95%CI 1.05–4.54) and all causes (RR = 1.91, 95%CI 1.51–2.42) after adjustment for potentially confounding variables. For never-married women, there was a smaller but significantly higher risk of mortality from all causes (RR = 1.46, 95%CI 1.15–1.84). Divorced and widowed men showed moderately higher risks of mortality from cardiovascular disease, external causes and all causes compared with married men, but such a trend was not observed in women.
Single status was associated with a higher risk of mortality than was married status for both men and women. Divorce and widowhood were associated with elevated risk for men, but not for women. These findings suggest single, divorce and widowhood status constitute potentially adverse health effects.