In Europeans, neither a liberal (odds ratio, OR = 1.05; 95% confidence interval, CI = 0.85–1.31; p = 0.65) nor a conservative approach (OR = 0.95; 95% CI = 0.75–1.22; p = 0.70, Table 1 and Fig 1A) revealed evidence of a causal effect of circulating adiponectin levels on RA risk. Here, ADIPOQ is linked to rheumatoid arthritis.