Impact of cardiac resynchronization therapy-defibrillator implantation on the association between body mass index and prognosis in patients with heart failure

J Interv Card Electrophysiol. 2015 Sep;43(3):269-77. doi: 10.1007/s10840-015-0015-3. Epub 2015 May 24.

Abstract

Purpose: This study aimed to examine the association between body mass index (BMI) and prognosis in heart failure patients after cardiac resynchronization therapy-defibrillator (CRT-D) implantation.

Methods: We retrospectively investigated 125 patients (33 overweight [BMI ≥25 kg/m(2)], 75 normal weight [BMI 18.5-24.9 kg/m(2)], and 17 underweight patients [BMI <18.5 kg/m(2)]) who underwent CRT-D implantation. The clinical outcome endpoints were all-cause death and appropriate shock therapy.

Results: During the follow-up period (mean 3.1 ± 1.8 years), 23 patients died (1 [3.0 %] overweight, 17 [22.7 %] normal weight, and 5 [29.4 %] underweight patients), and appropriate shock events were observed in 14 patients (2 [6.1 %] overweight, 10 [13.3 %] normal weight, and 2 [11.8 %] underweight patients). All patients survived shock therapy. After adjusting for confounding factors, overweight patients had significantly fewer outcomes relating to all-cause death and appropriate shock events (hazard ratio 0.27, 95 % confidence interval 0.08-0.91, p = 0.034) than normal weight patients. However, the prognostic difference between overweight and normal weight patients could be diminished as a result of the successful shock therapies (p = 0.067). Additionally, prognosis did not differ between overweight and normal weight patients among the responders, but did differ among the non-responders. The underweight patients had a poorer prognosis after CRT-D implantation compared with the other groups.

Conclusions: Although high BMI was associated with better outcomes among heart failure patients with CRT-D implantations, the difference in the prognosis between overweight and normal weight patients was reduced because of defibrillator therapy and the improvement in cardiac function provided by CRT-D implantation.

MeSH terms

  • Aged
  • Body Mass Index*
  • Cardiac Resynchronization Therapy / mortality*
  • Comorbidity
  • Defibrillators, Implantable / statistics & numerical data*
  • Female
  • Heart Failure / mortality*
  • Heart Failure / prevention & control*
  • Humans
  • Incidence
  • Japan / epidemiology
  • Male
  • Obesity / mortality*
  • Prognosis
  • Retrospective Studies
  • Risk Factors
  • Survival Rate
  • Treatment Outcome