[Promoting community gathering places "Kayoinoba" for healthy aging reduce health inequalities among communities: An eight-year ecological study].

Objectives　This study aimed to investigate whether health inequalities among communities would be reduced by intensively enhancing the "Kayoinoba" program in model communities where many high-risk, older adults live.Methods　Kobe City and the Japan Gerontological Evaluation Study created a mail survey for older adults in 78 communities (community ≈ junior high school district) to conduct community diagnosis. Sixteen communities showed poor values along multiple dimensions of risk and required priority measures. From 2014 to 2019, we designated these 16 communities as model communities. Then, municipal officials and researchers cooperated to support the establishment and management of "Kayoinoba." By using four-waves of mail survey data (in 2011, 2013, 2016, and 2019 with n=8,872, 10,572, 10,063, and 5,759, respectively), secular transitions of nine intermediate outcome indicators (three=social participation, two=social network, and four=social support) and five health outcome indicators (physical function, malnutrition, oral function, cognitive function, and depressive symptoms) were compared between model (n=16) and non-model (n=62) communities via multilevel mixed-effects linear regression analysis.Results　In the 2011 and 2013 surveys, model communities showed poor value compared to the non-model communities in 13 of the 14 indicators. A significant interaction between the year and model/non-model communities was confirmed for four intermediate outcome indicators (sports and hobby group participation, number of friends met, and providing emotional support) and three health outcome indicators (oral function, cognitive function, and depressive symptoms). The differences were reduced or eliminated in the 2016 and 2019 surveys. For example, hobby group participation in 2011 was 29.7% vs. 35.0% in model vs. non-model communities; the difference narrowed to 35.2% vs. 36.1% (P=0.008). Similarly, providing emotional support increased from 83.9% vs. 87.0% to 93.3% vs. 93.3% (P=0.007). Depressive symptoms decreased from 31.4% vs. 27.2% to 18.6% vs. 20.3% (P<0.001).Conclusions　Promoting community gathering places "Kayoinoba" for six years in communities where many high-risk older adults live may foster social participation, networking, and support and may help reduce health inequalities among communities.