The ratio of the neutrophil leucocytes to the lymphocytes predicts the outcome after cardiac resynchronization therapy

Abstract

AIMS: The low lymphocyte counts and high neutrophil leucocyte fractions have been associated with poor prognosis in chronic heart failure. We hypothesized that the baseline ratio of the neutrophil leucocytes to the lymphocytes (NL ratio) would predict the outcome of chronic heart failure patients undergoing cardiac resynchronization therapy (CRT). METHODS AND RESULTS: The qualitative blood counts and the serum levels of N-terminal of the prohormone brain natriuretic peptide (NT-proBNP) of 122 chronic heart failure patients and 122 healthy controls were analysed prospectively in this observational study. The 2-year mortality was considered as primary endpoint and the 6-month reverse remodelling (>/=15% decrease in the end-systolic volume) as secondary endpoint. Multivariable regression analyses were applied and net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated. The NL ratio was elevated in chronic heart failure patients when compared with the healthy controls [2.93 (2.12-4.05) vs. 2.21 (1.64-2.81), P < 0.0001]. The baseline NL ratio exceeding 2.95 predicted the lack of the 6-month reverse remodelling [n = 63, odds ratio = 0.38 (0.17-0.85), P = 0.01; NRI = 0.49 (0.14-0.83), P = 0.005; IDI = 0.04 (0.00-0.07), P = 0.02] and the 2-year mortality [n = 29, hazard ratio = 2.44 (1.04-5.71), P = 0.03; NRI = 0.63 (0.24-1.01), P = 0.001; IDI = 0.04 (0.00-0.08), P = 0.02] independently of the NT-proBNP levels or other factors. CONCLUSION: The NL ratio is elevated in chronic heart failure and predicts outcome after CRT. According to the reclassification analysis, 4% of the patients would have been better categorized in the prediction models by combining the NT-proBNP with the NL ratio. Thus, a single blood count measurement could facilitate the optimal patient selection for the CRT.