Association between subjective memory complaints and mental health well‐being in urban community‐dwelling elderly in Japan

The prevalence of subjective memory complaints (SMC) among the elderly has been reported to be between 25% and 50%. Subjective memory complaints are currently the object of growing interest as a possible predictor for future dementia. However, the direct association between SMC and cognitive decline remains controversial. Our previous study based on 95 communitydwelling older adults aged 65 years and older showed that there was no relationship between objective memory impairment and SMC. Besides cognitive decline, variables such as education, sex, age and others might underlie SMC. As patients with SMC seem distressed by their subjective forgetfulness, we hypothesized that mental health well-being is an important correlate of SMC. Just a few community-based studies have investigated the relationship between SMC and mental health wellbeing in the elderly. We carried out a community-based, cross-sectional study that included 3195 Japanese persons who were: (i) community residents of Chiyoda ward, Tokyo, Japan; (ii) aged 65 years or older; and (iii) not having long-term care insurance certification. Each participant received a self-administered questionnaire. The questionnaire included items regarding SMC, sociodemographic factors (age, sex, years of education, living alone or not, at work or not, social support network) and health-related variables (subjective health, current physical illness, pain, instrumental activities of daily living [IADL], mental health well-being, daytime sleepiness), which might affect mental health well-being. Social support network was assessed by the Japanese version of the abbreviated Lubben Social Network Scale, mental health well-being by the World Health Organization Well-Being Index – five items, daytime sleepiness by the Japanese version of the Epworth Sleepiness Scale, and IADL by the Tokyo Metropolitan Institute of Gerontology Index of Competence. SMC were assessed by the question “Do you feel that your memory has worsened in the last 6 months? ” Data were analyzed using PASW Statistics version 18 for Windows (SPSS, Chicago IL, USA). The stepwise linear regression analysis was carried out with SMC as the dependent factor, entering all the health-related variables, and sociodemographic factors including education, sex and age as independent variables. The significance level was set at a = 0.05. A total of 2034 participants (815 males, 1219 females) returned the questionnaire (response rate = 63.7%). The respondents’ mean age was 74.6 1 6.4 years and mean years of education was 13.2 1 3.0 years. Participants with no missing values for SMC (n = 1952) were analyzed. Among participants, 45.9% had SMC (males, 44.4%; females, 46.8%; c = 1.14, P = 0.153). The stepwise linear regression on SMC is shown in Table 1. In the final model, the significant correlates of SMC were lower mental health well-being, older age, daytime sleepiness, pain and lower IADL. The result shows mental health well-being is indeed an important correlate of SMC. In conclusion, findings of the current study, based on 2034 participants aged 65 years and older, show that SMC are significantly associated with lower mental health well-being along with older age, daytime sleepiness, pain and lower IADL among community-dwelling older adults in Japan.