AIM How older adults develop sarcopenia in the community setting is unclear. Focusing on social engagement, we aimed to validate our hypothesized model of sarcopenia development with various contributing factors, such as physical activity, oral function, psychological status and nutritional status. We also clarified direct and indirect effects of social engagement, physical activity, nutritional status, oral function and psychological status on new-onset sarcopenia. METHODS We analyzed 1483 participants' (72.6 ± 5.4 years) longitudinal data from the Kashiwa study. Sarcopenia was assessed in all the surveys in the Kashiwa study. Measures regarding social engagement, physical activity, oral function, psychological status and nutritional status were assessed at baseline. Structural equation modeling was used to analyze the efficiency of the hypothesized model, and calculate direct and indirect effects of factors affecting new-onset sarcopenia. RESULTS Over the follow-up period (median 6 years [interquartile range 4-6 years]), 12% of individuals developed new-onset sarcopenia. Our structural hypothesis model starting from social engagement to new-onset sarcopenia was suitable (root mean square error of approximation = 0.031, goodness-of-fit index = 0.967, adjusted goodness-of-fit index = 0.954, comparative fix index = 0.911, parsimonious comparative fit index = 0.755; all paths were significant), showing direct effects of social engagement on psychological status, physical activity and oral function, and indirect effects on nutritional status through oral function and psychological status. CONCLUSIONS The present results showed that social engagement could potentially decrease new-onset sarcopenia risks by influencing multidimensional factors, such as physical activity, oral function, and psychological and nutritional status. To prevent sarcopenia, it might be essential to promote social engagement through populational approaches. Geriatr Gerontol Int 2022; ••: ••-••.
Impact of social engagement on the development of sarcopenia among community-dwelling older adults: A Kashiwa cohort study.