Serum oxalate concentration is associated with coronary artery calcification and cardiovascular events in Japanese dialysis patients

Coronary artery calcification (CAC) is associated with cardiovascular disease (CVD). CAC might contain calcium oxalate, and a high serum oxalate (S Ox ) concentration is associated with cardiovascular mortality in dialysis patients. We assessed the associations between S Ox and CAC or cardiovascular events in Japanese hemodialysis patients. In 2011, 77 hemodialysis patients underwent multi-detector spiral computed tomography, and Agatston CAC score was calculated. Serum samples were collected and frozen in 2011, and S Ox concentrations were retrospectively measured in 2021. Also, new-onset CVD events in 2011–2021 were recorded. The association between S Ox concentration and CAC score ≥ 1,000, and new-onset CVD events were examined by logistic regression, Kaplan–Meier, and Cox proportional hazard models, respectively. Median S Ox concentration and CAC score were 266.9 (229.5–318.5) µmol/L and 912.5 (123.7–2944), respectively. CAC score was associated with S Ox (adjusted odds ratio [OR] 1.01, 95% confidence interval [CI], 1.00–1.02). The number of new-onset CVD events was significantly higher in patients with S Ox ≥ median value (hazard ratio [HR] 2.71, 95%CI 1.26–6.16). New-onset CVD events was associated with S Ox ≥ median value (adjusted HR 2.10, 95%CI, 0.90–4.91). S Ox was associated with CAC score and new-onset CVD events in Japanese hemodialysis patients.