OA is considered an inflammatory condition with systemic inflammation being a hallmark feature in its development; elevation in interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α) and C-reactive protein (CRP). Chronic exposure to these inflammatory cells has been shown to induce cartilage catabolism and increase pain. Coincidentally, obese people are characterised by having larger concentrations of these inflammatory cytokines.
Diet-induced weight loss plus exercise has a significantly greater improvement in pain and function as well as lower markers of IL-6 compared to exercise or diet alone.
There also appears to be a dose response to weight loss with greater weight loss being shown to have a more significant worthwhile impact on pain. Significant weight loss also effectively drops inflammatory markers of IL-6, CRP and TNF- α than does no weight loss.
In RCTs, the addition of weight loss for the management of OA seems to trump exercise each time and has more favourable effects on inflammatory markers and pain.
It is advocated that overweight individuals with OA should aim for a reduction in body weight by 10 per cent in order to have worthwhile improvements in pain and function.
Mark Anile, APAM
inmotion, September 2016