Neutrophil-to-Lymphocyte Ratio and Mortality in Cardiovascular Disease or Cancer: A Population-Based Cohort Study

Background: Inflammation contributes to development and progression of cardiovascular disease (CVD) and cancer. Whether the neutrophil-to-lymphocyte ratio (NLR), routinely available from blood counts, predicts prognosis in the general population is uncertain. Objectives: The purpose of this study was to evaluate the association of NLR with mortality in people with and without CVD or cancer. Methods: In this retrospective cohort study, we used National Health Service records from the Greater Glasgow & Clyde region for people aged >50 years in 2012. Participants were classified hierarchically into 5 exclusive groups: history of cancer, heart failure (HF, or dispensed loop diuretics), CVD, CV risk factors only, or none. Mortality was tracked until December 2019. Results: We identified 223,388 people with NLR measured between 2014 and 2015: 106,973 (48%) with CV risk factors only, 14,490 (7%) with CVD, 23,009 (10%) with HF or dispensed loop diuretics, 8,677 (4%) with cancer, and 70,239 (31%) none of these features. Median NLR was lowest in the latter group (2.0 [1.5-2.7]) and highest in those with HF or dispensed loop diuretics (2.7 [1.9-3.9]) or cancer (2.7 [1.9-4.1]). Median follow-up was 5.0 years (IQR: 4.4-5.0). In models adjusted for age, sex, estimated glomerular filtration rate, and hemoglobin, the highest NLR quartile predicted higher mortality across all groups (HR [95% CI] 2.07 [1.98-2.17] for CV risk factors and 2.18 [2.02-2.36] for none; 1.87 [1.70-2.04] for CVD, 2.10 [1.98-2.24] for HF or loop diuretics, and 2.30 [2.10-2.52] for cancer). Conclusions: Higher NLR is associated with greater mortality in adults with and without CVD, HF or cancer, suggesting it could enhance population risk scores.