Metabolic Syndrome and Risk of Atrial Fibrillation in Chronic Kidney Disease

Introduction Metabolic syndrome is a potent risk factor for adverse cardiovascular outcomes including atrial fibrillation (AF). Although metabolic syndrome is common among patients with chronic kidney disease (CKD), its association with AF remains unclear. Methods We analyzed 4,641 participants in the Chronic Renal Insufficiency Cohort (CRIC) without baseline AF. Cox regression models evaluated the association of a metabolic syndrome score (Adult Treatment Panel III criteria), its components (hypertension, diabetes, waist circumference, elevated triglycerides, low HDL), and markers of visceral adiposity (waist-to-height ratio and fat mass index) with time to hospitalization with AF. The main model adjusted for demographics, stroke, lifestyle factors (smoking, alcohol use), and whether participants had ever been seen by a nephrologist (as a marker of healthcare utilization). An exploratory model additionally adjusted for laboratory parameters (eGFR, proteinuria, hemoglobin, albumin, and electrolytes), other cardiovascular comorbidities, and medications. Results Mean age was 59 ±11 years, 44% were female, and 42% were Black. Over mean follow-up of 9.3 years, 616 (13%) were hospitalized with AF. Higher metabolic syndrome score was associated with hospitalization with AF (adjusted hazard ratio (aHR) per unit 1.16; 95%CI 1.08, 1.24). Elevated waist circumference and hypertension were the most consistently associated individual components, remaining independently associated with hospitalization with AF across all models including with concomitant adjustment for the remaining metabolic syndrome components (aHR 1.29; 95%CI 1.05, 1.60 and aHR 1.61; 95%CI 1.09, 2.39, respectively). Waist-to-height ratio and fat mass index, were also associated with hospitalization with AF in the main adjusted model (aHR per 0.1 unit, 1.23; 95%CI, 1.14, 1.34 and aHR per 5 kg/m², 1.22; 95%CI, 1.12, 1.34, respectively). Conclusion Among adults with CKD and no prior AF, hypertension and anthropometric markers of visceral adiposity are independently associated with higher risk of hospitalization with AF. Future studies should explore mechanisms linking body composition to arrhythmia in CKD and whether reducing visceral adiposity could mitigate this risk.