Loss of body weight is dose-dependently associated with reductions in symptoms of hip osteoarthritis.

Background/objectives: While weight loss is recommended for managing hip osteoarthritis (OA), most evidence comes from knee OA studies, limiting its applicability to hip OA. This study addresses this gap by examining the effects of weight loss on hip OA symptoms.

Design and setting: A retrospective audit of routinely collected healthcare data from participants enrolled in the Osteoarthritis Healthy Weight for Life (OAHWFL) program, designed for individuals with knee or hip OA.

Participants: In total, 1714 adults with hip OA were selected from the OAHWFL program; 1408 completed the initial 18-week weight loss phase, while 306 did not complete it. After 18 weeks, participants transitioned to an indefinite weight maintenance phase.

Exposure: Percentage change in body weight from baseline at 18 weeks.

Outcomes: Changes in the five subscales of the Hip Disability and Osteoarthritis Outcome Score (HOOS) (Pain, Activity Limitations in Daily Living, Stiffness and Range of Motion, Sports and Recreation Function, and Hip-related Quality of Life) from baseline to 18 weeks.

Statistics: Linear regression, adjusted for sex and baseline values of age, weight, and respective HOOS scores, assessed the relationship between percentage weight change (analyzed as both a continuous variable and in categories: ≤2.5%, >2.5-5.0%, >5.0-7.5%, >7.5-10%, and >10% of baseline weight) and changes in all five HOOS subscales.

Results: At baseline, participants had a mean age of 65.14 years, 70% were female, and 78% were individuals with obesity (Body Mass Index ≥30 kg/m²). A statistically significant dose-response relationship was observed between weight loss and improvements in all HOOS subscales, with the greatest improvement in the Hip-related Quality of Life subscale (14.42 points, 31.14%) for >10% weight loss.

Conclusion: Our findings suggest that weight loss is associated with reduced symptoms of hip OA, supporting weight loss as an effective treatment strategy for hip OA.