Locomotive syndrome severity and physical frailty progression in community-dwelling older adults: A 1-year longitudinal study from the DETECt-L study.

Abstract

Frailty is a geriatric syndrome that increases susceptibility to adverse health outcomes, including falls, disability, and mortality. Locomotive syndrome (LS), characterized by declining mobility, is a known predictor of poor health outcomes in older adults. However, the longitudinal relationship between LS severity and physical frailty progression in community-dwelling populations remains unclear. This 1-year prospective cohort study included 252 community-dwelling older adults who were non-frailty at baseline. LS severity at baseline was classified into three categories-non-LS, LS Stage 1, and LS Stage 2 or 3-based on a standardized assessment. Physical frailty was assessed using the Japanese version of the Cardiovascular Health Study criteria, with physical frailty progression after 1 year defined as a transition from robust to pre-frailty or frailty, or from pre-frailty to frailty, over 1 year. Binary logistic regression analyses examined the association between LS severity at baseline and physical frailty progression at 1 year, adjusting for confounders such as age, sex, body mass index, pain, fall history, Timed Up and Go test, single -leg standing time, and baseline frailty status. The median participant age was 74 years (range, 65-89 years; women, 85.3 %). Among the participants, LS Stage 1 was the most common (53.6 %), while 21.7 % were at LS Stage 2 or 3. After 1 year, 16.9 % of participants exhibited physical frailty progression (from baseline to 1 year), 70.9 % remained stable, and 12.2 % showed improvement. Compared with the non-LS group, those with LS Stage 2 or 3 had a significantly greater risk of physical frailty progression (adjusted odds ratio [aOR], 4.89; 95 % CI, 1.18-20.3). LS Stage 1 was not significantly associated with physical frailty progression. While advanced LS (Stage 2 or 3) significantly predicts frailty progression, our findings pinpoint LS Stage 1 as the crucial window for preventive action. At this early stage, a subclinical increase in risk manifests as a twofold rise in the rate of worsening frailty. Effective prevention strategies must therefore be initiated at LS Stage 1 to alter the trajectory away from functional decline.