Association of Neutrophil-to-Lymphocyte Ratio With All-Cause Mortality in the Elderly Population in China: A Retrospective Cohort Study

Neutrophil-to-lymphocyte ratio (NLR) is an emerging systemic inflammation marker associated with disease progression and mortality in patients. However, there is limited research on the predictive value of NLR in the general population. This study aimed to investigate the relationship between NLR and all-cause mortality in an elderly Chinese population. A retrospective cohort study was conducted based on health examination in a community in Shanghai, China, between 2015 and 2020. Among 6364 participants (aged ≥ 55 years), a total of 169 (2.66%) participants died during a median follow-up period of 5.37 years. The median NLR was 1.63 (interquartile range: 1.29, 2.11). Multivariate analysis revealed that the upper 2 quartiles of NLR were positively associated with all-cause mortality (Q3 vs Q1: hazard ratio [HR] = 1.82, 95% confidence interval [CI]: 1.07-3.09; Q4 vs Q1: HR = 2.22, 95% CI: 1.34-3.68, P for trend <.001). The stratified and interaction analyses showed that age, sex, body mass index (BMI), history of diabetes, or history of hypertension did not significantly modify the association between NLR and all-cause mortality. Elevated NLR was independently associated with an increased risk of all-cause mortality in the elderly Chinese population.