Marginal Benefit with Diet and Exercise in Obese Knee Osteoarthritis Patients Save

The easiest intervention for knee osteoarthritis (diet and exercise) is also the most difficult for many patients; but do these work? A new study of a weight loss and exercise program in community settings shows only marginal benefits. 

A randomized, controlled, clinical trial of 823 knee osteoarthritis patients (mean age 65 yrs) who were either overweight or obese (body mass index ≥27) tested the efficacy of diet and exercise vs an attention control. This 18-month follow-up used pain as the primary outcome, as measured by the WOMAC knee pain score (0 to 20 [severe]; with a minimum clinically important difference [MCID] of 1.6). 

After 18 months, the adjusted mean difference in the WOMAC pain score was −0.6, a difference that met statistical significance, but not the MCID. Weight loss favored the diet and exercise group at 18 mos (mean change −7.7 kg vs −1.7 kg in the attention control group).

Thus despite an 18-month program of weight loss and exercise based in community settings, there was only a small difference in knee pain of uncertain clinical importance.