To analyse the causal associations of different physical measures with osteoarthritis knee (KOA).
Exposure factors (weight, body mass index (BMI), body fat percentage, waist circumference, hip circumference, waist–hip ratio (WHR), and basal metabolic rate (BMR)), and outcome factor KOA were analyzed by inverse-variance weighted (IVW) method, along with heterogeneity test, sensitivity and pleiotropy analyses. Meta-analysis was used to combine the effect values of IVW methods in different data sources.
Weight, BMI, body fat percentage, waist circumference, hip circumference and BMR analyses showed causal association with increased KOA risk, while WHR analysis indicated a reduction of the incidence of KOA. P-value for all the results was less than 0.05 and F-value large than 20. All results were negative for heterogeneity tests and sensitivity analyses, and there was pleiotropy in weight and BMR. Meta-analysis results showed that the results of Odds Ratios (95% Confidence Intervals) for Weight (1.43(1.35–1.51)), BMI (1.40(1.10–1.78)), body fat percentage (1.56(1.44–1.68)), waist circumference (1.40(1.10–1.78)), hip circumference (1.37(1.30–1.44)), WHR (0.86(0.71–1.04)) and BMR (1.36(1.27–1.46) were consistent with the ones by Mendelian randomization analyses.