Risk factors for a 6‐year decline in physical disability and functional limitations among elderly people with type 2 diabetes in the Japanese elderly diabetes intervention trial

Abstract

Type 2 diabetes increases the risk of disability. The purpose of this study was to clarify the explanatory factors for disability in Japanese diabetic elderly. The 6-year decline in physical disability and functional limitations was investigated among 317 elderly people with type 2 diabetes recruited in a large-scale prospective study of the Japanese Elderly Diabetes Intervention Trial. Information about diabetes, blood examinations and complications was obtained, and basic activities of daily living (ADL) and instrumental ADL (IADL) were assessed by total score of the Barthel index and the Tokyo Metropolitan Institute of Gerontology Index of Competence, respectively. After 6 years of follow up, 13.6% of patients had developed a new ADL disability and 38.3% had developed a new functional impairment. In the 65-74 years age group, basic ADL decreased only in males, whereas females became functionally impaired. In the 75-84 years age group, basic and IADL decreased in both males and females. Older age and metabolic syndrome were prognostic for impairment of basic ADL, whereas baseline IADL problems, lower cognitive function, physical inactivity and insulin therapy were significant predictors of a future decline in the IADL. This study identified several factors predicting the future decline of basic ADL and IADL in diabetic elderly patients, and provided a conceptual framework that might help to clarify the pathways leading to disability. Because the specific causes of each functional problem are modifiable, comprehensive treatment and care are needed to allow Japanese diabetic elderly patients to have more favorable living conditions.