THE ROLE OF BODY WEIGHT IN OSTEOARTHRITIS

摘要

Obesity is a risk factor for OA and a common comorbidityMaintaining ideal body weight throughout life decreases riskAbnormal body composition directly impacts response to therapy/prognosisWeight loss is the first choice of treatment for overweight/obese patients with OAIn people and pets obesity is a complex disorder involving food intake, physical activity, behavioral factors, socioeconomic factors, environment exposures, genetics, metabolism and the microbiome. The increasing prevalence of obesity makes it a major healthcare challenge in both human and veterinary medicine. Recent surveys suggest over half (54%) of dogs and more than two-thirds (70.7%) of people are overweight or obese. Osteoarthritis (OA) is typically a slowly progressive condition characterized bydegeneration of articular cartilage, proliferation of new bone and a variable inflammatory response within the synovial membrane. This condition is also of concern to human and veterinary health care teams because of its prevalence. In dogs, the overallprevalence of arthritis is estimated to be 20- 25% and approximately 23% of adults have doctor diagnosed arthritis.1 Pets and people share many obesity-related comorbidities, including OA. In people, obesity is a recognized as a robust risk factor for knee OA. A recent meta-analysis of prospective studies showed that overweight (2.45) and obese (4.55) are significantly associated with higher knee OA risk.2 Indeed, in that analysis the risk of knee OA increases by 35% with a 5 kg/m2 increase in body massindex (BMI). A dose-response meta-analysis indicates knee OA risk increases almost exponentially with an increase in BMI.3 Conversely weight loss reduces the risk for OA. In women, a 5.1 kg reduction in body weight (BW) over a 10-year period decreased the likelihood of developing symptomatic knee OA by 50%.4 In dogs risk factors include age, large or giant breeds, genetics, developmental orthopedic disease, trauma and obesity. One long term study documented that the prevalence and severity of OA is greater in dogs with body condition scores above normal (BCS 4-5/9).5 Not surprisingly 40% of dogs and 31% of people with arthritis are also overweight.6-7 The connection between obesity and OA is so significant a recent meta-analysis suggests eliminating obesity might prevent up to 50% of knee OA in the United States.