Sex Difference in the Relation Between Marital Status and Dementia Risk in Two Population-Based Cohorts.
BACKGROUND
The modifying effect of sex on the relation between marital status and dementia has yet to be determined.


OBJECTIVE
To examine if sex modifies the association between marital status and incident dementia.


METHODS
Population-based samples from the Mayo Clinic Study of Aging (MCSA, N = 3,471) and the Gothenburg H70 Birth Cohort Study (H70-study, N = 913) were used. A multiplicative interaction term was used to analyze the modifying effect of sex on the relation between marital status (married versus not married) and incident dementia using Cox regression models. Further, risk of dementia by marital status was also evaluated in models separated by sex.


RESULTS
In the MCSA, there was an interaction between marital status and sex in relation to dementia (p = 0.015). In contrast, in the H70-study, no significant interaction was observed (p = 0.28). Nevertheless, in both studies, not married men had increased risk of dementia compared to married men in models adjusted for age, education, and number of children (H70-study: 1.99; 1.06-3.76, MCSA: 1.43; 1.08-1.89). Associations remained similar after additional adjustment for depression, BMI, hypertension, dyslipidemia, and diabetes mellitus (H70-study: 2.00; 1.05-3.82, MCSA: 1.32; 0.99-1.76). Further, no significant association was observed between marital status and dementia in women (H70-study: 1.24; 0.82-1.89, MCSA: 0.82; 0.64-1.04).


CONCLUSION
Sex had a modifying effect on the association between marital status and incident dementia. In analyses separated by sex, not married men had an increased risk of dementia compared to married men, while no significant association was observed between marital status and risk of dementia in women.
['Najar|Jenna|J|', 'Aakre|Jeremiah A|JA|', 'Vassilaki|Maria|M|', 'Wetterberg|Hanna|H|', 'Rydén|Lina|L|', 'Zettergren|Anna|A|', 'Skoog|Ingmar|I|', 'Jack|Clifford R|CR|', 'Knopman|David S|DS|', 'Petersen|Ronald C|RC|', 'Kern|Silke|S|', 'Mielke|Michelle M|MM|']
sex differences marital status Dementia epidemiology risk factors