Psychological and mental states mediated the association between physical activity and self-rated health of Chinese centenarians

OBJECTIVE: Based on the China Hainan Centenarian Cohort Study, the world's largest and most up-to-date database of the centenarians, this study aimed to explore the association between activity of daily living (ADL) and self-rated health (SRH) and analyze the mediators that affect the interaction between these two factors. This study will reveal health status and provide study basis in the centenarians so as to achieve better health guidance and medical services for older population. METHODS: A total of 992 centenarians were included in this study with questionnaire survey, physical examination, and biological test. RESULTS: Gender, body mass index, low density lipoprotein cholesterol, and mini-mental state examination (MMSE) had positive correlations with ADL and SRH, while fasting blood glucose and geriatrician depression scale (GDS)-15 had negative correlations with ADL and SRH (all P < 0.05). The total association between ADL and SRH was 0.2500 [95% confidence interval (CI): 0.1960-0.3039], the direct association was 0.1437 (95% CI: 0.0885-0.1989), and the total indirect association was 0.1063 (95% CI: 0.0807-0.1347; all P < 0.001). GDS-15 and MMSE were mediating factors of ADL and SRH, with mediating associations of 0.0636 (95% CI: 0.0430-0.0866) and 0.0326 (95% CI: 0.0182-0.0479), respectively. CONCLUSIONS: ADL was directly associated with SRH and indirectly associated with SRH mediated by psychological and mental states in the centenarians. Therefore, if older population want to become healthy centenarians, they should not only focus on maintaining and improving physical activity, but also could not ignore the role of psychological and mental states.