Cholesterol and glucose levels belong to independent predictors of death and hospitalizations in patients with chronic systolic heart failure

Objective: To elucidate relationship of total cholesterol (TC) level to results of follow-up of patients (pts) with systolic chronic heart failure (CHF).

Methods: In a framework of various international and local trials we prospectively followed up 130 patients (pts) with stable NYHA class II-IV HF and ejection fraction (EF) 40% or less. Criterion of inclusion in this analysis was presence of TC value obtained at baseline examination for a given trial. Mean age of pts was 65 +/- 9 years, 78% were men. During follow-up (mean 1.3 +/- 0.8, median 1.4 years) we registered all deaths and hospitalizations for heart failure worsening.

Results: During follow up 31 pts died and 38 were hospitalized. Compared to the group of pts without these events, pts who died had higher baseline fasting glucose (7.8 +/- 3.6 vs. 6.7 +/- 2.1 mmol/L; p=0.026) and lower TC (5.09 +/- 1.57 vs. 5.50 +/- 1.31 mmol/L; p=0.052) levels. Compared to event-free group, those who were hospitalized had significantly lower hemoglobin (Hb) (135 +/- 17 vs. 143 +/- 15 g/L; p=0.010). Cox proportionate hazards model included age, sex, EF, NYHA class, BMI, hemoglobin, glucose, creatinine, TC, history of hypertension, smoking, presence of disturbances of cardiac rhythm and conduction, medications. Mortality risk correlated with glucose and TC levels; each 1-mmol/L increase in glucose concentration was associated with 17% increase of mortality risk [hazard ratio (HR) 1.17; 95% confidence interval (CI) 1.05 to 1.31, p=0.005], and each 1-mmol/L decrease in TC - with 26% increase of mortality risk (HR 0.74, 95%CI 0.55 to 1.00, p=0.052). Left bundle branch block (LBBB) was an independent predictor of mortality (HR 2.51, 95%CI 1.02 to 6.18, p=0.045). Heart failure hospitalizations were linked to hemoglobin level and NYHA class. Each 10-g/L decrease in hemoglobin was associated with 31% elevation of risk of hospitalization (HR 0.69, 95%CI 0.51 to 0.92, p=0.011). There was almost 5-fold difference in risk of hospitalization between NYHA class II and IV (HR 4.80, 95%CI 2.64 to 8.73, p < 0.001). Pts with glucose > 7.4 mmol/L, or TC < 4.0 mmol/L, or hemoglobin < 130 g/L (optimal specificity/sensitivity derived from ROC curves) were at higher risk of an event. Kaplan-Meier survival analysis revealed that pts with glucose > 7.4 mmol/L, TC < 4.0 mmol/L, hemoglobin < 130 g/L had significantly reduced survival: p=0.050, p=0.006, p=0.016, respectively.

Conclusions: In a homogeneous group of pts with chronic heart failure and low EF characterized by usual relationships between established factors of prognosis (NYHA class, hemoglobin, LBBB) and development of events lower TC and higher glucose levels were each associated with worse outcome.