Frailty and driving status associated with disability: a 24-month follow-up longitudinal study

OBJECTIVES: To examine the relationship of driving status and frailty with disability in older adults. DESIGN: A prospective study. SETTING AND PARTICIPANTS: The study included 8533 participants (mean age: 72.0±6.1 years (range: 60–98 years), women: 54.1%) in a community setting. MEASURES: Driving status and frailty were assessed at baseline. The clinical definition of frailty was used according to the Japanese Cardiovascular Health Study index. Disability was prospectively determined using a record of Japanese long-term care insurance (LTCI). RESULTS: During the follow-up period (mean duration: 23.5 months), 58 (0.7%) participants were regarded as moving out of the city, 80 (0.9%) participants had died and 311 (3.6%) participants were certified by LTCI. The proportion of disability was 1.3% among the not-frail group and 5.3% among the frail group. The proportion of disability was 2.5% in participants who were currently driving and 7.5% in those not driving. Based on frailty status and driving, participants were further classified into four groups: not frail and currently driving (n=2945), not frail and not driving (n=642), frail and currently driving (n=3598) and frail and not driving (n=1348). Compared with older adults who are not frail and driving, the combined status of frail and not driving (adjusted HR: 2.28; 95% CI: 1.47 to 3.52) and frail and driving (HR: 1.91; 95% CI: 1.30–2.81) were risk factors for disability. CONCLUSIONS: Not driving and frail were associated with a risk of disability in community-dwelling older adults.