How to Treat Osteoarthritis in Obese Patients?

The close association between osteoarthritis (OA) and obesity is well established. Mechanisms linking obesity and OA involve multifactorial phenomena such as systemic factors (i.e. adipokines and pro-inflammatory cytokines), hormonal disturbances (hyperinsulinemia) and muscule changes (i.e. sarcopenia and lower muscular tone). The concomitant increasing prevalence of the two diseases have major health, social and economic consequences. However, to date no specific recommendation for the medical management of obese patients with OA have been published. Current recommendations only specify that obese patients must lose weight and practice regular physical activity in addition to the usual care. Weight loss improves not only OA symptoms but also metabolic abnormalities and cardiovascular risk factors commonly altered in subjects with obesity. OA symptoms' improvement has been shown to become clinically relevant from a weight loss > 5% of the body weight. In case of morbid obesity, bariatric surgery may be the only alternative for pain relief. After bariatric surgery, an appropriate calcium and vitamin D intake is recommended, since it has been shown that bariatric surgery was associated with a reduction in the bone mineral density and increased risk of fractures. An exercise program is essential for preserving healthy muscles during weight loss. Non-steroidal anti-inflammatory drugs and corticosteroids must be avoided, especially in obese patients with metabolic syndrome. In such patients symptomatic slow acting drugs for OA (i.e. glucosamine, chondroitin) and some anti-oxidant drugs (i.e. curcumin, ginger extracts, copper) may be helpful thanks to their excellent benefit/risk ratio and their mode of action which may have a positive impact on both OA and obesity-related metabolic disorders. Recent research focuses on the development of molecules aimed for promoting the production of heme oxygenase (HO-1). HO-1 decreases the production of oxygen free radicals and protects tissues from oxidative stress in the insulin resistance syndrome. Intra-articular (IA) injections of hyaluronic acid and corticosteroid have few adverse events. However, physicians must inform patients that IA treatments have a lower success rate in obese patients than in those with normal body mass index. Spa therapy contributes to relief pain, favour weight-loss and reduces metabolic abnormalities with a favourable risk/benefit balance.