Association Between Neutrophil Percentage to Serum Albumin Ratio and in-Hospital Mortality of Patients with Chronic Obstructive Pulmonary Disease in Intensive Care Unit: A Retrospective Cohort Study

Abstract

Objective: This study aimed to investigate the potential correlation between the neutrophil percentage to serum albumin ratio(NPAR) and in-hospital mortality in critically ill patients with Chronic Obstructive Pulmonary Disease (COPD).

Patients and methods: This study employed a retrospective cohort design. A total of 599 COPD patients were included in this research. Clinical data from the MIMIC-IV (Medical Information Mart for Intensive Care IV) database were utilized. To determine whether a correlation exists between NPAR and in-hospital mortality, a multivariable logistic regression analysis was conducted. Subgroup analyses were performed, taking into account factors such as age, sex, diabetes, congestive heart failure, and ventilator use.

Results: Among the 599 patients studied, 114 (19.0%) experienced in-hospital mortality. In the multivariable logistic regression model, NPAR was positively correlated with in-hospital mortality; for each unit increase in NPAR, the in-hospital mortality rate increased by 5% (Odds Ratio [OR] = 1.05; 95% Confidence Interval [95% CI] = 1.02-1.09). Compared to the lowest NPAR group, the highest NPAR group had a significantly greater risk of in-hospital mortality (OR [95% CI] = 2.15 [1.11-4.17]). Furthermore, the results of the subgroup analyses were consistent across all groups.

Conclusion: Our study reveals a correlation between NPAR levels and mortality in COPD patients. Further research is warranted to validate these findings.

Keywords: MIMIC-IV; chronic obstructive pulmonary disease; hospital mortality; neutrophil percentage to serum albumin ratio; retrospective cohort study.

Figure 1

Diagram Illustrating the Enrollment of Participants. Symbols: (n=XXX): Represents the number of patients at each step.

Figure 2

Illustrates a forest plot that shows the relationship between the NPAR and mortality rates in hospitals. Bold text (eg, “Overall”, “Crude”, “Adjusted”) highlights key categories or analysis types. Symbols:OR (95% CI): Odds ratio with 95% confidence interval. P for interaction: P-value for interaction tests between subgroups. Event (%): Percentage of in-hospital mortality events in each subgroup. The crude analysis is presented without adjustments, while the adjusted analysis incorporates various covariates including gender, age, race, heart rate, systolic blood pressure (SBP), mean blood pressure (MBP), respiratory rate, oxygen saturation (SPO2), white blood cell count (WBC), platelet count, hemoglobin levels, anion gap, bicarbonate levels, blood urea nitrogen (BUN), creatinine levels, calcium levels, glucose levels, sodium levels; as well as whether or not there is congestive heart failure present along with mild liver disease, severe liver disease, metastatic solid tumors, renal disease diabetes mellitus.Additionally, the Charlson Comorbidity Index is taken into account alongside the Simplified Acute Physiology Score II (SAPS II) and the Sequential Organ Failure Assessment (SOFA) score, as well as the patient’s ventilation status.