Abstract 11961: Clinical, Physiologic, and Functional Characterization of Patients With Diabetes and Heart Failure With Preserved Ejection Fraction: Data From the Heart Failure Network RELAX Study
Background: Diabetes is associated with increased mortality and hospitalizations in patients with heart failure with preserved ejection fraction (HFpEF), but the underlying mechanisms for this relationship are not known. We hypothesized that HFpEF patients with diabetes represent a more severe phenotype of the disease and have reduced exercise capacity.
Methods: RELAX was a multicenter, randomized (sildenafil vs. placebo), 24-week trial that enrolled 216 stable outpatients with heart failure, EF≥50%, elevated BNP or intracardiac pressures, and reduced exercise capacity. We used baseline data and compared clinical, biomarker, echocardiographic, and exercise results between diabetic (n=93) and non-diabetic (n=123) patients using non-parametric and Chi-square tests. Linear models were used to assess peak VO2 and 6 min walk.
Results: There were numerous differences in clinical characteristics, left ventricular remodeling and function, and circulating biomarkers, between diabetic and non-diabetic patients with HFpEF (Table). Diabetic patients had lower baseline peak VO2 and shorter 6 min walk distance compared to non-diabetic patients and more hospitalizations for cardiovascular or renal causes over 6 months (Table). After adjustment for age, gender, and BMI, diabetes was associated with a lower peak VO2 (β=-1.48 ml/kg/min, p≤0.001) and shorter 6 min walk distance (β=-50 meters, p=0.001). Diabetic patients had increased resting E/e’, increased Galectin-3 levels, and a lower chronotropic index, each of which was associated with a lower peak VO2 (p≤0.001 for each).
Conclusions: Diabetic patients with HFpEF have a more severe phenotype of the disease with more co-morbidities, increased left ventricular hypertrophy, worse diastolic function, increased circulating markers of oxidative stress, inflammation, and fibrosis, and reduced exercise capacity. These mechanisms may contribute to worse clinical outcomes in diabetic patients with HFpEF.
- © 2013 by American Heart Association, Inc.