[Identification of dietary patterns and their relationship with physical performance in adults of 85 years of age and older -A cross sectional study from The Tokyo Oldest Old survey on Total Health study].

Aim: While the proportion of people of ≥85 years of age is expected to increase, there is limited research on the dietary patterns and physical performance of this population in Japan. The purpose of this study was to identify the dietary patterns of people of ≥85 years of age who live in Tokyo and to examine the relationship with their physical performance.

Methods: Using data from the baseline survey (conducted in 2008-2009) of The Tokyo Oldest Old survey on Total Health study, the estimated 58 food intake items were aggregated into 33 items after energy adjustment, and a principal component analysis was performed. For physical performance, the results of grip strength, chair standing test, and 3 m timed up and go test conducted at normal walking speed were used. A multiple regression analysis was used to adjust for confounders and to examine the relationship between each dietary pattern and physical performance.

Results: The subjects of the analysis were 87.3 (86.2-88.8) years of age (median [25-75th percentile] ). From the principal component analysis, three dietary patterns were identified: "various vegetable foods", "fish and mushrooms", and "cooked rice and miso soup". A higher propensity for the "fish and mushrooms" dietary pattern was significantly associated with grip strength (partial regression coefficient, B (95% confidence interval): 0.48 (0.13-0.83) ).

Conclusions: In a population of people of ≥85 years of age in Tokyo, a positive association was observed between hand grip strength and a dietary pattern characterized by fish and mushroom intake.