Abstract
INTRODUCTION: We have previously shown an association between metabolic syndrome (MS) and heart failure (HF) outcomes in patients with implantable cardioverter defibrillators (ICDs) or cardiac resynchronization therapy with defibrillator (CRT-D). However, the role of MS in predicting outcomes was not assessed in non-obese patients. We aimed to examine how the presence of MS and its components predicts the risk of HF/death in non-obese ICD or CRT-D patients. METHODS: We included obese and non-obese patients, enrolled in Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT). Patients needed at least 2 of the 3 criteria, dyslipidaemia, diabetes, or hypertension, to be considered for having MS. Kaplan-Meier analyses were used to assess the rate of HF/death by MS. Multivariate Cox-proportional analyses were performed to assess the risk of HF/death by MS. RESULTS: From 1180 (65%) non-obese patients in MADIT-CRT, 672 (57%) presented with MS. Among non-obese patients with MS, 284 (42%) had diabetes mellitus. Non-obese MS patients had a significantly higher, 34% cumulative probability of HF/death at 3 years, as compared to the 20% of non-obese patients without MS (log-rank P < .001) (hazard ratio: 1.64, 95% CI: 1.15-2.32, P & .006). Within non-obese MS patients, those with diabetes had a significantly higher rate of HF/death with 28% vs. 20% in non-diabetics at 2.5 years (log-rank P < .001). Reverse remodelling was similar in all subgroups. CONCLUSION: MS in non-obese ICD or CRT-D patients is associated with a higher risk of HF/Death, most prominent in those with diabetes, necessitating early intervention.