Metabolic Syndrome and Osteoarthritis Distribution in the Hand Joints: A Propensity Score Matching Analysis From the Osteoarthritis Initiative.

Objective To investigate the metabolic syndrome (MetS) association with radiographic and symptomatic hand osteoarthritis (HOA). Methods Using 1:2 propensity score matching for relevant confounders, we included 2509 participants (896 MetS positive and 1613 MetS negative) from the Osteoarthritis Initiative dataset. MetS and its components, according to the International Diabetes Federation criteria, were extracted from baseline data, and included hypertension, abdominal obesity, dyslipidemia, and diabetes. We scored distinct hand joints based on the modified Kellgren-Lawrence (mKL) grade of baseline radiographs, with HOA defined as mKL ≥ 2. In the cross-sectional analysis, we investigated the association between MetS and its components with radiographic HOA and the presence of nodal and erosive HOA phenotypes using regression models. In the longitudinal analysis, we performed Cox regression analysis for hand pain incidence in follow-up visits. Results MetS was associated with higher odds of radiographic HOA, including the number of joints with OA (OR 1.32, 95% CI 1.08–1.62), the sum of joints mKLs (OR 2.42, 95% CI 1.24–4.71), mainly in distal interphalangeal joints (DIPs) and proximal interphalangeal joints (PIPs; OR 1.52, 95% CI 1.08–2.14 and OR 1.38, 95% CI 1.09–1.75, respectively), but not metacarpophalangeal (MCP) and first carpometacarpal (CMC1) joints. Hand pain incidence during follow-up was higher with MetS presence (HR 1.25, 95% CI 1.07–1.47). The erosive HOA phenotype and joints9 nodal involvement were more frequent with MetS (OR 1.40, 95% CI 1.01–1.97 and OR 1.28, 95% CI 1.02–1.60, respectively). Conclusion MetS, a potentially modifiable risk factor, is associated with radiographic DIP and PIP OA and longitudinal hand pain incidence while sparing MCPs and CMC1s. Nodal and erosive HOA phenotypes are associated with MetS, suggestive of possible distinct pathophysiology.