Association of body mass index and prognosis in patients with HFpEF: A dose-response meta-analysis

Background: Although agreements regarding the negative effects of obesity on the development of heart failure with preserved ejection fraction (HFpEF) have been reached, the relationship between body mass index (BMI) and adverse outcomes in HFpEF patients are still debatable. Therefore, we conducted the dose-response meta-analysis to investigate this relationship. Methods: We searched the PubMed and Embase databases up to February 2022 for studies that evaluated the association between BMI and prognostic outcomes in patients with HFpEF. A cubic spline random-effects model was used to fit the potential dose-response curve. The effect estimates were expressed as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Results: A total of 11 studies involving 69,273 patients with HFpEF were included. The summary HR for all-cause mortality was 0.90 (95% CI, 0.84-0.95) per 5 units increase in BMI, but the association was U-shaped (P-nonlinear < 0.01) with the nadir of risk at a BMI of 32-34 kg/m(2). The summary HR for HF hospitalization was 1.12 (95% CI, 1.05-1.19) with a significant positive linear association (P-nonlinear = 0.54). Conclusions: For patients with HFpEF, there was a positive linear association of BMI with HF hospitalization, while a U-shaped relationship between BMI and all-cause mortality was observed with the lowest event rate at a BMI of 32-34 kg/m(2).