Usefulness of total lymphocyte count as predictor of outcome in patients with chronic heart failure.

Low lymphocyte count has been considered a predictive marker of unfavorable outcomes for patients with heart failure (HF). Baseline blood samples for complete blood counts, differential counts, renal function tests. and lipid profile were prospectively obtained to assess the association between lymphocyte count and clinical outcomes in 305 patients with HF (average New York Heart Association [NYHA] class 2.8). The mean follow-up duration was 4.7 years (range 8 months to 8.4 years), and 111 patients (36%) died during the follow-up period. The mean lymphocyte count for the group was 1,803.64 ± 740.3, and the mean left ventricular ejection fraction (LVEF) was 37%. Patients with low lymphocyte counts (<1,600 median count) after 8 years had significantly lower survival rates than those with lymphocyte counts ≥1,600 (58% vs 72%, p=0.012). The prediction of poorest survival was for patients in NYHA class III or IV and with lymphocyte counts <1,600. Regression analysis showed that lymphocyte level, the LVEF, and NYHA class were predictors of mortality. Of these, NYHA class was the most prominent predictor, followed by lymphocyte count, which was even more significant than the LVEF (hazard ratio 0.76, p=0.037). In conclusion, the findings of this study demonstrate that total lymphocyte count is an important prognostic factor, inversely associated with predicted mortality. Although the total low lymphocyte count was correlated with a lower NYHA class and a lower LVEF, it emerged as an independent death risk factor in patients with chronic HF.