Neutrophil-to-lymphocyte ratio used as prognostic factor marker for dilated cardiomyopathy in childhood and adolescence

OBJECTIVE: The objective of this study is to evaluate the neutrophil-to-lymphocyte ratio (NLR) and platelet–lymphocyte ratio, from the hemograms obtained from children and adolescents with dilated cardiomyopathy (DCM), and to correlate them with the levels of B-type natriuretic peptide (BNP) and with the clinical evolution of these patients in the long term. MATERIALS AND METHODS: Follow-up of 57 patients with DCM was made retrospectively, with hemogram and BNP level determination being performed after optimized therapy for heart failure. We compared the findings of the patients' examinations that progressed with stability in relation to the occurrence of transplant listing, cardiac transplantation, or evolution to death. RESULTS: The average age was 48 months, and the follow-up was 64 months. The average of the levels of neutrophils was greater in poor evolution group (7026 vs. 3903; P = 0.011) as well as the average of NLR (5.5 vs. 1.9; P = 0.034). The averages of hemoglobin, total leukocytes, lymphocytes, and platelets were similar in the groups. The area under the receiver operating characteristic curve for NLR in relation to the poor evolution was of 72.9%, being the best cutoff point of NLR ≥5.2 (sensitivity: 93.8% and specificity: 87.8%). Kaplan–Meier curves demonstrate that patients with NLR ≤5.2 (P = 0.001) and BNP <1000 pg/dl (P < 0.0001) presented greater survival. CONCLUSIONS: NLR (≥5.2) and lymphopenia (≤1000 lymphocyte/μL) were associated with a poor prognosis and a higher chance of evolution to death or cardiac transplant, similar to the findings for BNP.