Weight gain is associated with worse knee symptoms in community-based men and women: A longitudinal study.

Abstract

Aim: To examine the association between change in weight and change in WOMAC pain, stiffness and function scores. Method(s): 250 subjects aged 25-62 years were recruited. Subjects completed a questionnaire at baseline and mu2 years later. Pain, stiffness and function were assessed by the Western Ontario and McMaster University Osteoarthritis Index (WOMAC). Result(s): Fifty-two subjects (21%) were of acceptable weight (BMI < 25 kg/m2), 46 subjects (18%) were overweight (BMI 20-25 kg/m2) and 148 subjects (59%) were obese (BMI >=30 kg/m2). At baseline, those who were obese had greater median WOMAC scores compared to those who were acceptable weight or overweight. One hundred and ninety-eight subjects (79%) were followed up. Fiftyeight subjects (29%) lost >=5% of baseline weight, 110 subjects (56%) remained stable (+/-<5% baseline weight) and 30 subjects (15%) gained >=5% of baseline weight. Losing >=5% of baseline weight was associated with reduced WOMAC stiffness score compared to those who remain stable (mean difference-13.4mm, 95% CI-25.3,-1.6 mm). Similar trends were observed in those non-obese and without radiographic OA (ROA). Gaining >=5% of baseline weight was associated with increased WOMAC pain score by 26.0mm (95% CI 2.6, 49.3mm) and WOMAC function score by 87.8mm (95% CI 6.7, 168.9mm) compared to remaining stable weight. Similar trends were observed in the obese and ROA subgroups. Conclusion(s): This study demonstrates that weight gain is associated with worse knee symptoms, with a more modest benefit of weight loss, thus highlighting the potential benefit of avoiding weight gain in the management of knee pain.