Impact of components of metabolic syndrome on the risk of adverse renal outcomes in patients with atrial fibrillation: a nationwide cohort study

BACKGROUND: The renal effect of metabolic syndrome components is unclear in patients with atrial fibrillation. This study aimed to investigate the association between metabolic syndrome components and incident end-stage renal disease among patients with atrial fibrillation. METHODS: A total of 202,434 atrial fibrillation patients without prevalent end-stage renal disease were identified from the National Health Insurance Service database between 2009 and 2016. We defined the metabolic score range from 0 to 5 points such that a patient received every 1 point if the patient met each component listed in the diagnostic criteria of metabolic syndrome. The population was divided into 6 groups: MS(0)–MS(5) for a metabolic score of 0–5, respectively. Multivariate Cox regression analysis was used to estimate the risks of end-stage renal disease. RESULTS: There were 12,747, 31,059, 40,361, 48,068, 46,630, and 23,569 patients for MS(0)–MS(5), respectively. Compared with MS(0), MS(5) had a higher CHA(2)DS(2)-VASc score (3.8 vs. 1.0) (P < .001). During a median follow-up of 3.5 years, compared with MS(0), MS(1)–MS(5) were associated with a gradually increasing incidence of end-stage renal disease, in relation to an increase in the metabolic score, (log-rank P < .001). After multivariate adjustment, a higher metabolic score was associated with a greater risk of incident end-stage renal disease: adjusted hazard ratio [95% confidence interval] = 1.60 [0.78–3.48], 2.08 [1.01–4.31], 2.94 [1.43–6.06], 3.71 [1.80–7.66], and 4.82 [2.29–10.15], for MS(1)–MS(5), respectively. CONCLUSIONS: Metabolic syndrome components additively impacts the risk of incident end-stage renal disease among patients with atrial fibrillation.