Predictive Validity of Different Walking Measures to Identify the Incident Long-Term Care Needs in Older Adults

Objectives A comfortable walking speed is a suitable measurement of functional status in older adults. In addition to assessing their comfortable walking speed, two complex walking tests were administered to a cohort of older people, assuming that these tests would be a more sensitive predictor of the incident long-term care needs than comfortable walking speed. Design A prospective observational study was conducted to collect data. Setting and Participants Among the initial 5,563 community-dwelling independent older adults (aged ≥ 65 years), 935 were excluded and the data of 4,628 (mean age, 73.9 ± 5.5 years, 65–94 years; 2,052 men, 2,576 women) older adults were finally analyzed. Methods Three walking tasks were administered: comfortable, complicated balance, and Go-stop walking. Complicated balance walking was measured under comfortable walking conditions, with participants having to walk with their hands crossed at the shoulder joint at 90°. For the Go-stop walking test, the time taken to walk 2 meters was measured using a stopwatch. For two years following baseline assessments, participants received monthly follow-ups for incident certification of the need for care under the long-term care insurance (LTCI) system. Results Low performance in comfortable, complicated balance, and Go-stop walking were 29.8%, 37.7%, and 35.1%, respectively. During the 24-month follow-up period, 246 participants (5.3%) required LTCI certification. The Youden Index was used to determine the cut-points of the incident long-term care needs in the comfortable, complicated balance, and Go-stop walking conditions, which were 1.055 m/s, 0.936 m/s, and 3.205 seconds, respectively. Participants classified as exhibiting low performance included 1,381 (29.8%) under comfortable walking, 1,746 (37.7%) under complicated balance walking, and 1,623 (35.1%) under the Go-stop walking tests. The C-indices of the comfortable, complicated balance, and Go-stop walking tests were 0.72 (95% confidence interval (CI) 0.69–0.76), 0.71 (95% CI 0.67–0.74), and 0.65 (95% CI 0.61–0.69), respectively. Cox proportional hazards regression model revealed significant relationships between the incident long-term care needs and the comfortable (hazard ratio (HR) 2.14, 95% CI 1.62–2.84), complicated balance (1.81, 1.36–2.41), and Go-stop (1.46, 1.12–1.91) walking conditions. Conclusions and Implications The findings suggest that slow walking speed has a considerably greater impact on the incident long-term care