Performance-based assessments and demand for personal care in older Japanese people: a cross-sectional study

OBJECTIVES To identify appropriate clinical tests for determining the demand for personal care in older Japanese people. DESIGN Cross-sectional observation study. SETTING Obu Study of Health Promotion for the Elderly (Obu, Aichi) and Tsukui Ordered Useful Care for Health (241 day-care centres) cohorts in Japan. PARTICIPANTS A total of 10 351 individuals aged 65 years or older (6791 with personal care and 3560 without personal care) participated in the study. MEASURES Physical performance tests included grip strength, the chair stand test, walking speed at a comfortable pace, and the timed up-and-go test. Personal care was defined as participants who had been certified in the national social long-term care insurance in Japan. RESULTS Individuals who received personal care showed a significantly poorer performance than those without personal care for all physical performance tests (p<0.001). Gait speed was the most useful of the physical performance tests to determine the demand for personal care (receiver operating characteristic curve statistics: men, 0.92; women, 0.94; sensitivity: men, 86; women, 90; specificity: men, 85; women, 85). After adjustment for age, sex, cognitive impairment and other physical tests, all physical performance tests were individually associated with the demand for personal care. A slow gait speed (<1 m/s) was more strongly correlated with the demand for personal care than other performance measures (gait speed OR: 5.9; 95% CI: 5.0 to 6.9). CONCLUSIONS Clinical tests of physical performance are associated with the demand for personal care in older people. Preventive strategies to maintain physical independence may be required in older adults who show a gait speed slower than 1 m/s. Further research is necessary to confirm these preliminary results.