[Predictive value of neutrophil to lymphocyte ratio in the progression of sepsis to chronic critical illness in elderly patients].

OBJECTIVE

To explore the predictive value of neutrophil to lymphocyte ratio (NLR) in the progression of sepsis to chronic critical illness (CCI) in elderly patients.

METHODS

Patients with sepsis who were hospitalized more than 24 hours and older than 60 years old admitted to the department of medical intensive care unit (MICU) of General Hospital of Southern Theatre Command from August 2019 to April 2021 were enrolled. The neutrophil count (NEU), lymphocyte count (LYM) and NLR of peripheral blood cells were recorded on the 1st, 4th and 7th day after admission. Patients were divided into the CCI group and the non-CCI group according to whether they progressed to CCI, and differences between the two groups were compared. The CCI was defined as a MICU length of stay (LOS) ≥ 14 days and persistent organ dysfunction [sequential organ failure assessment (SOFA) score ≥ 2]. Logistic regression analysis was performed to evaluate the risk factors for predicting CCI. The receiver operator characteristic curve (ROC curve) was plotted for evaluating the predictive value of NLR in the progression of sepsis to CCI in elderly patients.

RESULTS

(1) Among 103 sepsis patients enrolled, 16 (15.5%) died within 2 weeks of admission to the MICU, 46 (44.7%) developed CCI, and 41 (39.8%) were non-CCI. (2) Compared between the two groups, the NEU of CCI group on day 7 was significantly higher than that of non-CCI group [×10/L: 9.80 (6.72, 16.80) vs. 6.66 (5.14, 9.29), P < 0.01], LYM was significantly lower than that of non-CCI group [×10/L: 0.77 (0.46, 1.20) vs. 1.00 (0.86, 1.48), P < 0.05], and NLR on day 4 and day 7 were significantly higher than those of non-CCI group [12.85 (6.56, 17.56) vs. 8.26 (5.34, 13.17), 13.76 (6.97, 23.66) vs. 6.14 (4.04, 8.84), both P < 0.05]. Compared with different time points in the same group, NEU and NLR decreased gradually and LYM increased gradually in non-CCI group (χ values were 10.216, 28.343, 7.189, respectively, all P < 0.05), which tended to be normal. There were no significant differences in NEU, LYM and NLR of CCI group at each time point (χ values were 0.798, 4.478, 5.783, respectively, all P > 0.05). (3) Multivariate Logistic regression analysis showed that NLR on day 7 was an independent risk factor for sepsis progression to CCI [odds ratio (OR) = 1.155, P = 0.005]. (4) ROC curve analysis showed that the area under the curve (AUC) of NLR predicting the sepsis progression to CCI on day 7 was 0.775, and the 95% confidence interval (95%CI) was 0.670-0.860, P < 0.01; when the cut-off value was 9.25, the sensitivity was 69.57% and the specificity was 80.56%.

CONCLUSIONS

Dynamic monitoring of NLR is helpful to determine the progress of sepsis in elderly patients, NLR on day 7 has a certain predictive value for the occurrence of CCI.