Chen D, Xu H, Sun L, et al. - According to findings from this Mendelian randomization (MR) study, there exists no bidirectional causal effect of urate levels and gout on total and site-specific osteoarthritis (OA).

• The bidirectional link between OA and urate levels and gout, though well-documented, remains inconclusive.

• Data were obtained from 288,649 CKDGen participants and from 69,374 Global Urate Genetics Consortium participants, to assess the bidirectional causality between OA and urate levels as well as gout via this MR study.

• No association existed between genetically determined urate levels [inverse variance weighted (IVW) odds ratio (OR) = 0.99] and gout (Wald ratio OR = 1.00) and the risk of total OA.

• In site-specific OA analyses, urate levels had no causal impact on knee, hip, spine, thumb and hand OA, and no evidence was gained that gout elevated the risk of OA at any site.

• In the reverse MR studies, total OA had no causal effect on urate levels (IVW Beta = -0.011) or gout (IVW OR = 1.05).

• A null impact of site-specific OA was also noted.