Effects of metabolic syndrome on cardiovascular outcomes in non-obese heart failure patients.

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.