Risk of psychological distress in partners with functional disability among older Japanese adults

Aim: The present cross-sectional study aimed to evaluate the association of psychological distress with a partner's disability in an older Japanese population, as well as the effect modification of social support on this association. Methods: The baseline survey was carried out between 1 December and 15 December 2006, and included 6809 participants from whom we collected data regarding functional disability and psychological distress. We defined functional disability as certification for long-term care insurance in Japan, and psychological distress as a Kessler 6 score of ≥10 out of 24. A multiple logistic regression analysis was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for increased psychological distress according to the categories of functional disability among partners. Stratified analyses were also carried out to investigate whether social support significantly affected the association between a partner's functional disability and psychological distress. Results: The multiple-adjusted OR for psychological distress was 1.48 (95% CI 1.06–2.04) among participants whose partners had functional disabilities (vs those whose partners did not have functional disabilities). In the social support-stratified analysis, a significant association with psychological distress was observed among participants lacking social support for help with their daily housework (OR 2.47, 95% CI 1.23–4.83), but not among those with social support (OR 1.18, 95% CI 0.79–1.72); P for interaction = 0.03). Conclusions: A partner with functional disability conferred a significantly higher risk of psychological distress on older Japanese individuals, and this association was modified by social support. We conclude that social support might buffer psychological distress in this population. Geriatr Gerontol Int 2018; 18: 775–782.