Association between the incidence of functional disability and frequency of eating together among older adults living alone: a 6-year follow-up study from the Japan Gerontological Evaluation Study

OBJECTIVE: This study aimed to determine whether the frequency of eating together is associated with the incidence of functional disability in older adults who live alone. METHODS: This 6-year observational prospective cohort study utilised self-reported questionnaires. Data were drawn from the participants of the Japan Gerontological Evaluation Study project between 2016 and 2022. The participants were independent older adults aged ≥65 years living alone in Japan. The primary outcome was the incidence of functional disability during the follow-up period, with the self-reported frequency of eating together serving as the explanatory variable. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards models after adjusting for confounders associated with incident functional disability. RESULTS: Among the 7167 participants, the mean age at baseline was 75.3 ± 6.5 years and 69.2% were female. About, 12.8% of participants (n = 917) developed functional disabilities during the observation period. The incidence rates were 11.7% for 'every day', 11.3% for 'several times a week', 11.5% for 'several times a month', 12.7% for 'several times a year' and 19.0% for 'seldom'. The frequency of eating together 'seldom' was significantly associated with an increased incidence of functional disability (HR: 1.55, 95% CI: 1.10-2.18). CONCLUSION: Among older adults living alone, infrequent eating together ('seldom') was identified as a risk factor for developing functional disability.