Aussie researchers have worked out how much weight people carrying extra kilograms with knee osteoarthritis need to shed to improve the situation.
It’s at least 7.7% of total body weight!
This is the key number to aim for in weight loss for knee osteoarthritis. Achieving this leads to clinically meaningful improvement in people’s ability to function in their daily lives and leads to reductions in the pain suffered.
The study does show that weight loss is dose dependent. This means that those who shed more weight, have greater improvements.
The study included 1383 people with knee osteoarthritis who were either overweight or obese, and enrolled in a community-based weight loss program. The program used a dietary intervention, exercise and online, phone or email support and motivation.
Around 85% of the participants were obese with a mean BMI of 34.4 and 71% were women.
Over the 18-week study period, 95% lost over 2.5% of their body weight, with almost a third dropping over 10%.
Obesity is clearly associated with poor outcomes in knee osteoarthritis, partly because of the adverse mechanical effects and partly due to obesity-related inflammation. This is not emphasised enough in consultation rooms, and even when it is, not enough effort is put into achieving weight loss (read about the IDEA trial here).
This study seems to show that it’s feasible to focus on dietary intervention, coupled with motivational support in a community setting as a way to improve the symptoms of knee osteoarthritis.