Decline in independence after three years and its association with dietary patterns and frailty factors in community-dwelling older people: an analysis by sex and age stage
Background Support based on sex and age is required to implement longevity strategies. This study clarified the association between declining independence after three years and the dietary patterns and frailty factors of community-dwelling independent older people. We analyzed sex and age stages for people between 65 and 75 years (earlier-stage) and people aged 75 years or above (latter-stage), respectively. Methods In a longitudinal study of 25 Japanese prefectures from 2013 to 2016, 3,693
... to 2016, 3,693 respondents completed baseline and follow-up questionnaires. We analyzed 2,250 participants (1,294 men), after excluding individuals younger than 65 years (n = 510), deceased (n = 35), with missing data (n = 866), or disabled (n = 32). Independence was evaluated based on Instrumental Activities of Daily Living (IADL) scores (maximum = 12). Disability was defined as scoring lower than 9. Dietary patterns were derived from a principal component analysis of 7 food groups. Frailty factors showing a significant relationship with baseline IADL scores were selected. Multivariate logistic regression analysis revealed an association between baseline factors and declining independence after three years. Results The average IADL score three years from baseline was 11.5 ± 1.1. There were two IADL score groups: "high independence" (69.6%) and "low independence" (30.4%). Three baseline dietary patterns were identified: "dietary diversity," "high meat frequency," "low fruit, vegetable, and dairy product frequency." The multivariate-adjusted model in the earlier-stage revealed that BMI ≥ 30 (odds ratio (OR) = 0.97, 95% confidence interval (CI): 0.12-7.61) showed no significant difference from 18.5 < BMI (OR = 1). In the latter stage, subjective health and exercising three or more times a week with enjoyment were associated with a lower odds ratio. High meat frequency was related to high OR in all groups, especially latter-stage older women (OR = 1.59, 95% CI: 1.17‐2.15). Conclusions Effective integrated support for maintaining independence may be associated with weight management for earlier-stage men, the mental/psychological factors in subjective health and exercise enjoyment for latter-stage older people, and limited meat consumption, especially for latter-stage older women.