Individuals with Multi‐Joint Osteoarthritis Demonstrate Larger Longitudinal Declines in Frailty: Data from the Canadian Longitudinal Study on Aging
Carson Halliwell, Rebecca Moyer, Myles W. O'BrienObjective
Test the hypothesis that multi‐joint osteoarthritis would modify the relation between time and frailty progression, where more affected joints would lead to larger declines over 6‐years compared to those without osteoarthritis using data from the Canadian Longitudinal Study on Aging.
Methods
Frailty was quantified using a frailty index at baseline, 3‐year, and 6‐year follow‐up. Osteoarthritis was self‐reported physician diagnosis of knee, hip, or hand. Participants were categorized as having none, one, two, or three affected joints at baseline. Linear mixed‐effects models adjusted for age, body mass index, marital status, sitting time, light‐moderate physical activity, strenuous physical activity, and sex were performed to test the interaction between time and multi‐joint osteoarthritis on frailty trajectories over 6‐years.
Results
13,757 participants were included (mean frailty: 0.16±0.05); 10,193 had no osteoarthritis, 2,535 had one affected joint, 806 had two, and 223 had three. Individuals without osteoarthritis had the lowest baseline frailty, followed stepwise by one‐joint group, two‐joint group, and three‐joint group (p<0.001). Baseline multi‐joint osteoarthritis was positively associated with frailty progression over 6‐years [β=0.105, 95%CI: 0.027:0.170]. Frailty slopes across groups were; no osteoarthritis [β=0.237, 95%CI: 0.225:0.247], one‐joint group [β=0.293, 95%CI: 0.262:0.310], two‐joint group [β=0.348, 95%CI: 0.327:0.368], and three‐joint group [β=0.330, 95%CI: 0.291:0.371]. Frailty progressed faster in multi‐joint (≥2 joint group) versus single‐joint osteoarthritis [β=0.070, 95%CI: 0.029:0.109].
Conclusion
Individuals with osteoarthritis affecting two‐or‐three joints experienced a 40‐47% faster rate of frailty progression compared with those without osteoarthritis despite starting at a higher baseline frailty, highlighting multi‐joint involvement as a marker of heightened risk of accumulating health deficits.