Background: Low aerobic capacity is a strong and independent predictor of all-cause mortality for both diabetic patients and chronic heart failure (CHF) patients. We tested the hypothesis that coexistance of type 2 diabetes lowers peak aerobic capacity in patients with CHF.

Methods: We retrospectively studied 276 CHF patients with or without type 2 diabetes who underwent cardiopulmonary exercise testing (CPET). All CHF patients had a history of hospital admission due to worsening HF with either non-reduced left ventricular ejection fraction (LVEF; ≥40%) or reduced LVEF (<40%).

Results: Peak oxygen uptake (VO2) was significantly decreased in diabetic group compared to nondiabetic group not only in total CHF population (median 13.8 [interquartile range 11.8-16.4] vs. 16.4 [13.2-20.2] mL/kg/min) but also in CHF patients with LVEF ≥40% (14.1 [12.4-16.6] vs. 17.4 [13.9-20.7] mL/kg/min) and in CHF patients with LVEF <40% (13.4 [10.3-16.3] vs. 16.0 [12.5-20.0] mL/kg/min). There was an inverse correlation between peak VO2 and glycosylated hemoglobin in total CHF population (r=-0.16, P=0.017). Multivariate analysis showed that the presence of type 2 diabetes was an independent predictor of the lowered peak VO2 in CHF patients with LVEF ≥40% and <40%, respectively, after adjustment for age, gender, anemia, renal function, LVEF, and B-type natriuretic peptide.

Conclusions: Type 2 diabetes is an independent predictor of the lowered peak VO2 in CHF patients. The presence of type 2 diabetes has a negative impact on peak aerobic capacity in CHF patients with both reduced and non-reduced LVEF.


T. Abe: None. T. Yokota: None.

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