Effects of body mass index on worsening of heart failure and all-cause death in patients with heart failure and reduced left ventricular ejection fraction: a 10-year follow-up study

Abstract Background/Introduction Obesity in patients with heart failure (HF) with reduced ejection fraction (HFrEF) is common, and with the emergence of effective anti-obesity drugs, a better understanding of the relation between BMI and clinical outcome in HFrEF is needed. Purpose This study aimed to analyse whether a body mass index (BMI) above 27 kg/m2 (cut-off used in trials) is associated with a greater rate of all-cause death and HF hospitalization in patients with HFrEF. Methods We included 1,017 medically optimized according to existing HF guidelines at the time and clinically stable HF patients with a left ventricular ejection fraction of <45% from the NorthStar study. Patients were included between 2005 and 2009 and followed for 10 years using Danish nationwide registries. The outcomes of interest were all-cause death and hospital discharge for HF (overnight stay). Descriptive statistics were grouped according to tertiles of BMI. The association between BMI as a continuous variable and the outcomes of interest was analysed using restricted cubic splines in Cox proportional-hazards models. Reported were hazard ratios (HR) with 95% confidence intervals (CI) adjusted for relevant prognostic covariates (reference: BMI = 27 kg/m2). Results At enrolment, the median age was 69 years, 75% were men, and the median BMI was 26.3 kg/m2 (Table 1). Patients in the upper 3rd BMI tertile were younger (median age 67), had a lower level of NT-proBNP level (median 737.5 pg/ml) and a higher proportion of diabetes (29.9%). During 10 years of follow-up, HF hospitalization occurred in 683 patients (61.7%), and 623 patients died (56.3%). A BMI above 27 kg/m2 was associated with a higher rate of HF hospitalization (significantly from BMI 35.2 kg/m2: HR 1.30 [CI 1.00-1.68]; Figure 1). Similar findings were observed for all-cause mortality (significantly from BMI 35.7 kg/m2: HR 1.27 [CI 1.00-1.62]) Conclusion In patients with HFrEF, a BMI above 27 kg/m2 was associated with a higher rate of HF hospitalization and all-cause death. Efforts to find effective and safe approaches to reducing weight in obese patients with HFrEF are warranted.Figure 1