Objective: Most guidelines recommending weight loss for hip osteoarthritis are based on research on knee osteoarthritis. Prior studies found no association between weight loss and hip osteoarthritis, but no previous studies have targeted older adults. We aimed to determine whether there is any clear benefit of weight loss for hip osteoarthritis in older adults, because weight loss is associated with health risks in older adults. Methods: We used data from white females aged ≥ 65 years from the Study of Osteoporotic Fractures. Our exposure of interest was weight change from baseline to follow up at 8 years. We investigated the following 15 outcomes over the 8 years: total hip replacement (THR); development of hip pain; resolution of hip pain; development of radiographic hip osteoarthritis (RHOA); development of symptomatic RHOA; progression of RHOA; and degeneration of 9 individual structural features of the hip (as visualized by radiography). Generalized estimating equations (clustering of 2 hips per female) were used to investigate the association between exposure and outcomes adjusted for major covariates. Results: There was a total of 11,018 hips from 5509 females. There was no associated benefit of weight loss for any of the 15 outcomes. For example, the odds ratio (95% confidence interval) for THR was 0.98 (0.87 to 1.11) for each 5% weight loss. The results were consistent across subgroups defined by overweight and obese body mass index and intention to lose weight. Conclusion: Our findings suggest no associated benefit of weight loss in older women in reducing the incidence.
Zubeyir Salis, University of New South Wales, Australia
Li-Yung Lui, California Pacific Medical Center Research Institute, United States
Nancy Lane, University of California at Davis, United States
Kristine Ensrud, University of Minnesota, United States
Amanda Sainsbury, The University of Western Australia, Australia