Different characteristics of chronic heart failure (CHF) in elderly diabetics and non-diabetics

Higher plasma concentrations of the N-terminal fragment of brain natriuretic peptide (NT-pro-BNP) and the tumor necrosis factor-alpha (TNF-alpha) have been observed in patients affected by chronic heart failure (CHF). Recent clinical studies have tried to correlate the plasma levels of these biomarkers with severity of the disease. To evaluate the role of NT-pro-BNP, TNF-alpha and C-reactive protein (CRP) in a population of geriatric patients affected by CHF, and to assess their different plasma levels in diabetics and in normoglycemic patients, we enrolled 57 patients affected by CHF: 29 patients were diabetic and 28 were normoglycemic. Clinical and echocardiographic examinations were performed in all patients, in order to evaluate the NYHA-class and the left ventricular ejection fraction (EF). All of them had been stabilized with medical therapy from at least 3 weeks. Plasma NT-pro-BNP, TNF-alpha and CRP levels were measured in each recruited patient. In the whole population we observed a linear correlation between NT-pro-BNP levels, EF and NYHA-class (p<0.05) but there was no significant correlation between TNF-alpha or CRP and the clinical or echocardiographic data (p=0.588 and p=0.9, respectively). Finally we evaluated, if there were significant differences in the biomarker concentrations between diabetics and normoglycemics. Both the clinical and the echocardiographic parameters of systolic dysfunction were comparable in these two groups. We observed a significant difference in CRP levels between the two groups (3.76+/-2.85 in diabetics vs. 1.42+/-2.35 in normoglycemics; p<0.001). The NT-pro-BNP levels were also higher in diabetics than in normoglycemic patients (12867.8+/-18042.0 vs. 6400.89+/-5655.0; p=0.07). Plasma TNF-alpha levels (23.03+/-11.52 vs. 23.31+/-12.0; p=0.93) and left ventricular EF (35.65+/-4.03 vs. 35.18+/-3.55; p=0.63) were similar in the two groups. In agreement with recent studies, we confirm a linear correlation between NT-pro-BNP, EF and the severity of disease in CHF patients. We also observed a greater cytokine activation in diabetics than in normoglycemic patients, demonstrating probably that in this group a greater inflammatory reaction is present.