Immunosenescence is the age-related changes in the immune system, namely, progressively higher levels of circulating inflammatory markers, characteristics changes of circulating immune subset cells and altered immune function. The neutrophil to lymphocyte ratio (NL ratio) has been identified as a prognostic indicator for neoplastic disease progression, in predicting chronic degenerative diseases, and as a potential indirect marker of healthy aging. This study aims to examine the longitudinal association of neutrophil, lymphocyte absolute count, and their ratio with longitudinal risk for multimorbidity and mortality. The Baltimore Longitudinal Study of Aging (BLSA) is an open observational cohort study of community-dwelling volunteers that are followed every 1–4 years depending on their age. The sample considered in the study consists of 1769 participants (5090 follow-ups) with completed data for physical examination, health history assessment, and donated a blood sample. The NL ratio increased with age and was associated with a higher risk of mortality, while a lower NL ratio was inversely correlated with multimorbidity. Neutrophils increased with aging and an increase in their absolute number predicted mortality risk. However, the absolute number of lymphocytes was associated with age only in a cross-sectional analysis. In conclusion, this study supports the importance of the NL ratio and absolute neutrophil count as markers of aging health status, and as significant predictors of all-cause mortality and multimorbidity in aging individuals. It remains to be demonstrated whether interventions contrasting these trends in circulating cells may result in improved health outcomes.

免疫衰老是免疫系统中与年龄相关的变化，即循环炎症标志物水平逐渐升高、循环免疫亚群细胞特征变化和免疫功能改变。中性粒细胞与淋巴细胞比率（NL 比率）已被确定为肿瘤疾病进展、预测慢性退行性疾病的预后指标，以及健康衰老的潜在间接标志。本研究旨在检查中性粒细胞、淋巴细胞绝对计数及其比率与多种发病率和死亡率纵向风险的纵向关联。巴尔的摩老龄化纵向研究 (BLSA) 是一项针对社区志愿者的开放观察性队列研究，根据志愿者的年龄，每 1-4 年进行一次随访。研究中考虑的样本由 1769 名参与者（5090 名随访者）组成，他们拥有完整的体检数据、健康史评估数据和捐献的血液样本。NL 比率随着年龄的增长而增加，并与较高的死亡风险相关，而较低的 NL 比率与多重发病率呈负相关。中性粒细胞随着年龄的增长而增加，其绝对数量的增加预示着死亡风险。然而，淋巴细胞的绝对数量仅在横断面分析中与年龄相关。总之，本研究支持 NL 比率和绝对中性粒细胞计数作为老龄化健康状况标志以及作为老龄化个体全因死亡率和多发病的重要预测因素的重要性。与循环细胞的这些趋势相反的干预措施是否可以改善健康结果仍有待证明。