['Atrial fibrillation (AF) is closely associated with metabolic syndrome, and the receptor for advanced glycation end products (RAGE) pathway is involved in insulin resistance and cardiac remodelling. We hypothesized that plasma level of soluble RAGE (sRAGE) would predict clinical outcome after radiofrequency catheter ablation for AF.', 'We measured pre-procedural plasma level of sRAGE in 496 patients who underwent AF ablation (142 patients with diabetes, 354 patients without diabetes selected by matching them with diabetic patients according to age, sex, and AF type). (i) Plasma level of sRAGE was significantly higher in diabetic patients than in non-diabetics (580.0 ± 576.4 vs. 435.8 ± 280.7 pg/mL, P = 0.005), but there was no difference in sRAGE levels between patients with clinical recurrence of AF and those without. (ii) During 24.5 ± 18.0 months of follow-up, the recurrence of AF was significantly lower in the diabetic patient group with high sRAGE (≥418 pg/mL based on the median value) than the diabetic patient group with low sRAGE (log-rank P = 0.045). This was especially pronounced in patients with paroxysmal AF and diabetes (log-rank P = 0.016), but no association was found in non-diabetics. (iii) In multivariate Cox regression analysis, high sRAGE (HR 0.395, 95% CI 0.175-0.894, P = 0.026) and paroxysmal AF (HR 0.387, 95% CI 0.179-0.835, P = 0.016) were independently associated with the favourable clinical outcome of rhythm control after AF ablation in diabetic patients.'] Is high plasma level of soluble RAGE independently associated with a low recurrence of atrial fibrillation after catheter ablation in diabetic patient?