Singer SP, et al. - The goal of this study was to shed light on the link between obesity (current and historic) and osteoarthritis (OA) of the knee or hip. Researchers inferred that OA of the hip or the knee is better predicted by the maximum body mass index (BMI) over one’s lifespan vs the current BMI. An association of current BMI was evident, only with knee OA but not with hip OA, and therefore, it seemed as if knee joint is more sensitive to obesity.

Methods

• Researchers performed a case–control study to assess 99 people (knee OA, hip OA and controls), age > 50 years.
• The current weight, height and waist circumference were measured on site, and detailed weight changes over their lifetime were based on questionnaires and standardized interviews.
• Using binomial logistic regression, researchers determined the predictive value for an osteoarthritis group membership of each derived indicator.

Results

• Findings demonstrated that an increase in ‘maximum-BMI’ increased the odds ratio for both knee OA (OR 1.2; CI 1.1–1.4;p=0.005; R² = 0.36) and hip OA (OR 1.2; CI 1.0–1.3; p=0.027; R² = 0.16).
• Researchers observed a significant association of current BMI with knee OA but not with hip OA.
• Furthermore, they found that a high “minimum-BMI” (over the age of 18 years) had the highest odds ratio of all calculated indicators for both osteoarthritis groups.