High Neutrophil-to-Albumin Ratio Predicts Postoperative Pneumonia in Aneurysmal Subarachnoid Hemorrhage

Neutrophil-to-albumin ratio as a predictor of mortality in patients with intracerebral hemorrhage: a multicenter retrospective cohort study

BACKGROUND

Intracerebral hemorrhage (ICH) is associated with a poor prognosis. The association between the neutrophil-to-albumin ratio (NAR) with mortality in patients with ICH remains underexplored. This study investigated the relationship between the NAR and mortality in patients with ICH.

METHODS

A multicenter retrospective observational cohort study was conducted from January 2010 to June 2019. Participants were divided into four groups according to NAR quartiles at admission. Univariable and multivariable logistic regression analyses were used to evaluate the relationship between NAR and 90-day mortality. The predictive power of NAR was compared with neutrophil count and albumin levels using receiver operating characteristic (ROC) curve analysis.

RESULTS

Patients in the highest NAR quartile had significantly greater odds of 90-day mortality (adjusted OR 1.74, 95% CI 1.27-2.39, p < 0.001) compared to those in the lowest quartile. The area under the curve (AUC) for NAR was 0.68, demonstrating superior discriminative ability compared to neutrophil count (AUC 0.64) and albumin (AUC 0.60). These findings were consistent across various subgroups, with multivariate analysis confirming the independent predictive value of NAR for mortality in patients with ICH.

CONCLUSIONS

Elevated NAR was independently associated with increased mortality in patients with ICH. NAR is a promising inflammatory marker that could aid in early risk assessment and guide management strategies for patients with ICH.

Nomogram for predicting the development of pneumonia after colorectal cancer surgery

The aim of this study was to analyze the factors contributing to the development of pneumonia after colorectal cancer (CRC) surgery and to develop a validated nomogram to predict the risk. We retrospectively collected information on patients who underwent radical CRC resection at a single clinical center from January 2011 to December 2021. The information was then randomly assigned to a training cohort and a validation cohort in a 7:3 ratio. Univariate and multivariate logistic regression analysis were performed on the training cohort to identify independent risk factors for the development of pneumonias, which were then included in the nomogram. Validation was performed in a validation cohort, area under the curve (AUC) and calibration curves were used to determine the predictive accuracy and discriminative power of the graphs, and decision curve analysis (DCA) was used to further substantiate the clinical efficacy of the nomogram. A total of 7130 patients were included in the study. Based on multivariate logistic regression analysis of the training cohort, age, sex, preoperative albumin, surgical methods, and surgical time were identified as independent risk factors for the development of pneumonia after CRC surgery, and a nomogram prediction model was established using the above five variables. The AUC was 0.745 in training cohort and 0.773 in validation cohort. This study established a nomogram that is a good predictor of the risk of developing pneumonia after CRC surgery and provided surgeons with a reference for personalized management of patients in the perioperative period.

The association between neutrophil to high-density lipoprotein cholesterol ratio and gallstones: a cross-sectional study

OBJECTIVE

Several studies have discussed the relationship between cholesterol and gallstones, and high-density lipoprotein cholesterol (HDL-C) as a representative of this has been addressed in various diseases. The metric neutrophil to high-density lipoprotein cholesterol ratio (NHR) derived from HDL-C has attracted much attention. The purpose of this article is to examine the relationship between NHR and gallstones in a population of American adults.

METHODS

This study investigated the correlation between NHR and gallstone prevalence among US adults using population-based data from the 2017-2020 National Health and Nutrition Examination Survey (NHANES). NHR was derived by dividing the neutrophil count by HDL-C. Data were analyzed using a variety of statistical techniques, such as univariate analysis, multivariate analysis, and subgroup analysis. In addition, a receiver operating characteristic curve (ROC) was used to determine the predictive power of the index for the risk of gallstone prevalence.

RESULTS

The trial enrolled 6,954 subjects, among whom 746 patients were diagnosed with gallstones. By fully adjusted multivariate logistic regression analysis in the Model 3 section observed a significant positive association between NHR and gallstones with an odds ratio (OR) of 1.05 and a 95% confidence interval (CI) of (1.01, 1.10). The restricted cubic curve (RCS) had a P-Nonlinear = 0.481, suggesting that the relationship was a near-linear one. The area under the curve (AUC) of the ROC curve was 0.550, indicating that NHR has a predictive value for the development of gallstones.

CONCLUSION

This study demonstrated a near-linear correlation between NHR and increased susceptibility to gallstones, and the ROC curve is evidence that NHR has some predictive value for the risk of gallstones, albeit with weak predictive power relative to NPAR (Neutrophil percentage/albumin) and NAR (Neutrophils/albumin). Of course, to confirm these findings, more extensive prospective studies are needed to thoroughly validate the role of NHR in the development of gallstones.

Immunoinflammatory markers SIRI and NAR as predictors of respiratory distress syndrome and secondary infections in premature infants

Background

Premature infants are at high risk for neonatal respiratory distress syndrome (RDS) and secondary infections. This study aims to investigate the association between immunoinflammatory markers-the systemic immune inflammation index (SII), systemic inflammation response index (SIRI), and neutrophil-to-albumin ratio (NAR)-and the risk of developing RDS in premature infants.

Methods

A total of 2164 premature infants were enrolled in this retrospective study. The clinical records of these neonates (respiratory tract infections, adverse pregnancy history, placental abnormalities, birth weight, Apgar scores, and immunoinflammatory indices) were collected. Comparisons were made between infants with and without RDS. Logistic regression analysis was used to evaluate the relationship between SII, SIRI, NAR and RDS.

Results

Among the cohort, 962 infants developed RDS, while 1202 did not. The RDS group showed higher proportions of mothers with adverse pregnancy history, placental abnormalities, birth weight <2.5 kg, and lower Apgar scores at 1 and 5 minutes (all p<0.05). SII, SIRI, and NAR levels were significantly elevated in RDS infants (p<0.05). Logistic regression revealed that adverse pregnancy history (OR: 1.390, p=0.001), placental abnormalities (OR: 2.499, p<0.001), birth weight <2.5 kg (OR: 4.165, p<0.001), high SIRI (OR: 1.338, p=0.035), and high NAR (OR: 1.639, p<0.001) were significant predictors of RDS. Additionally, secondary infections, particularly pneumonia and sepsis, were significantly more common in the RDS group (p<0.001).

Conclusion

Adverse pregnancy history, placental abnormalities, low birth weight, elevated SIRI and NAR were associated with increased risk of RDS and secondary infections in premature infants. These findings suggest that SIRI and NAR could serve as useful markers for early identification and management of RDS and its complications in this vulnerable population.

Development and validation of a machine-learning model for predicting postoperative pneumonia in aneurysmal subarachnoid hemorrhage

Pneumonia is a common postoperative complication in patients with aneurysmal subarachnoid hemorrhage (aSAH), which is associated with poor prognosis and increased mortality. The aim of this study was to develop a predictive model for postoperative pneumonia (POP) in patients with aSAH. A retrospective analysis was conducted on 308 patients with aSAH who underwent surgery at the Neurosurgery Department of the First Affiliated Hospital of Soochow University. Univariate and multivariate logistic regression and lasso regression analysis were used to analyze the risk factors for POP. Receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the constructed model. Finally, the effectiveness of modeling these six variables in different machine learning methods was investigated. In our patient cohort, 23.4% (n = 72/308) of patients experienced POP. Univariate, multivariate logistic regression analysis and lasso regression analysis revealed age, Hunt-Hess grade, mechanical ventilation, leukocyte count, lymphocyte count, and platelet count as independent risk factors for POP. Subsequently, these six factors were used to build the final model. We found that age, Hunt-Hess grade, mechanical ventilation, leukocyte count, lymphocyte count, and platelet count were independent risk factors for POP in patients with aSAH. Through validation and comparison with other studies and machine learning models, our novel predictive model has demonstrated high efficacy in effectively predicting the likelihood of pneumonia during the hospitalization of aSAH patients.

Predictive Value of Fibrin Fibrinogen Degradation Products-to-Potassium Ratio for Poor Functional Outcome in Patients with Aneurysmal Subarachnoid Hemorrhage: A Retrospective Case-Control Study

BACKGROUND

The relationship of fibrin(ogen) degradation products (FDPs) and potassium with the functional outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) is still uncertain. This study aims to evaluate the predictive value of a novel combination biomarker, the FDP-to-potassium ratio (FPR), for poor functional outcomes in patients with aSAH.

METHODS

A total of 425 consecutive patients with aSAH at a single center were retrospectively enrolled in our study. An unfavorable outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 3 months after discharge. Univariate analysis and multivariable logistic regression were performed for baseline information and laboratory parameters recorded at admission. In addition, the receiver operating characteristic curve was plotted, and propensity score matching was performed based on the FPR.

RESULTS

On the basis of mRS grade, 301 patients were classified as having favorable outcomes, and 124 patients were assessed as having unfavorable outcomes. FPR levels were significantly correlated with mRS grade (r[Spearman] = 0.410; P < 0.001). Multivariate logistic regression analysis showed that age (odds ratio [OR] 1.043, 95% confidence interval [CI] 1.016-1.071; P = 0.002), white blood cell count (OR 1.150, 95% CI 1.044-1.267; P = 0.005), potassium (OR 0.526, 95% CI 0.291-0.949; P = 0.033), World Federation of Neurosurgical Societies grade (OR 1.276, 95% CI 1.055-1.544; P = 0.012), and FPR (OR 1.219, 95% CI 1.102-1.349; P < 0.001) at admission were independently associated with poor functional outcomes. The DeLong test showed that the area under the receiver operating characteristic curve of FPR was higher than that of age, white blood cell count, potassium, World Federation of Neurosurgical Societies grade, or FDP alone, indicating that FPR had better predictive potential than these other variables. After 1:1 propensity score matching (FPR ≥ 1.45 vs. FPR < 1.45), the rate of poor prognosis was still significantly increased in the high-FPR group (48/121 [39.7%] vs. 16/121 [13.2%], P < 0.001).

CONCLUSIONS

Fibrin(ogen) degradation product-to-potassium ratio is an independent predictor of poor outcomes for patients with aSAH and may be a promising tool for clinicians to evaluate patients' functional prognosis.

Development and performance assessment of novel machine learning models for predicting postoperative pneumonia in aneurysmal subarachnoid hemorrhage patients: external validation in MIMIC-IV

Background

Postoperative pneumonia (POP) is one of the primary complications after aneurysmal subarachnoid hemorrhage (aSAH) and is associated with postoperative mortality, extended hospital stay, and increased medical fee. Early identification of pneumonia and more aggressive treatment can improve patient outcomes. We aimed to develop a model to predict POP in aSAH patients using machine learning (ML) methods.

Methods

This internal cohort study included 706 patients with aSAH undergoing intracranial aneurysm embolization or aneurysm clipping. The cohort was randomly split into a train set (80%) and a testing set (20%). Perioperative information was collected from participants to establish 6 machine learning models for predicting POP after surgical treatment. The area under the receiver operating characteristic curve (AUC), precision-recall curve were used to assess the accuracy, discriminative power, and clinical validity of the predictions. The final model was validated using an external validation set of 97 samples from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database.

Results

In this study, 15.01% of patients in the training set and 12.06% in the testing set with POP after underwent surgery. Multivariate logistic regression analysis showed that mechanical ventilation time (MVT), Glasgow Coma Scale (GCS), Smoking history, albumin level, neutrophil-to-albumin Ratio (NAR), c-reactive protein (CRP)-to-albumin ratio (CAR) were independent predictors of POP. The logistic regression (LR) model presented significantly better predictive performance (AUC: 0.91) than other models and also performed well in the external validation set (AUC: 0.89).

Conclusion

A machine learning model for predicting POP in aSAH patients was successfully developed using a machine learning algorithm based on six perioperative variables, which could guide high-risk POP patients to take appropriate preventive measures.

A High Immediate Postoperative Neutrophil-to-Albumin Ratio is Associated With Unfavorable Clinical Outcomes at Hospital Discharge in Patients With Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Inflammation is associated with unfavorable clinical outcomes after aneurysmal subarachnoid hemorrhage (aSAH). We evaluated the relationship between postoperative neutrophil-to-albumin ratio (NAR) and unfavorable clinical outcomes (modified Rankin score ≥ 3) at hospital discharge in aSAH patients.

METHODS

Five hundred sixty aSAH patients undergoing surgical or endovascular treatment were included in this retrospective study. Patients were initially allocated to high (n=247) or low (n=313) postoperative NAR groups based on the immediate postoperative NAR cutoff value identified by receiver operating characteristic analysis, and then further subclassified into 4 groups: HH (high pre- and high postoperative NAR, n=156), LH (low preoperative and high postoperative NAR, n=91), HL (high preoperative and low postoperative NAR, n=68), and low pre- and low postoperative NAR (n=245).

RESULTS

Optimum cutoff values of immediate postoperative and preoperative NAR were 2.45 and 2.09, respectively. Unfavorable clinical outcomes were more frequent in patients with high compared with low postoperative NAR (45.3% vs. 13.4%; P < 0.001). In multivariate analysis, postoperative NAR was a significant predictor of unfavorable clinical outcomes (odds ratio, 2.10; 95% CI, 1.42-3.10; P < 0.001). Unfavorable clinical outcomes were less frequent in group low pre- and low postoperative NAR than in groups HH, LH, and HL (9.4% vs. 44.9%, 46.2% and 27.9%, respectively; all P < 0.001) and also in Group HL compared with groups HH and LH ( P =0.026 and P =0.030); clinical outcomes did not differ between Groups HH and LH.

CONCLUSIONS

A high immediate postoperative NAR was associated with unfavorable clinical outcomes at hospital discharge in aSAH patients.

Association between neutrophil-to-albumin ratio and long-term mortality of aneurysmal subarachnoid hemorrhage

OBJECTIVE

The prognosis of aneurysmal subarachnoid hemorrhage (aSAH) survivors is concerning. The goal of this study was to investigate and demonstrate the relationship between the neutrophil-to-albumin ratio (NAR) and long-term mortality of aSAH survivors.

METHODS

A retrospective observational cohort study was conducted at Sichuan University West China Hospital between January 2009 and June 2019. The investigation of relationship between NAR and long-term mortality was conducted using univariable and multivariable Cox regression models. To demonstrate the predictive performance of different biomarkers over time, time-dependent receiver operating characteristic curve (ROC) analysis and decision curve analysis (DCA) were created.

RESULTS

In total, 3173 aSAH patients were included in this study. There was a strong and continuous relationship between NAR levels and long-term mortality (HR 3.23 95% CI 2.75-3.79, p < 0.001). After adjustment, the result was still significant (adjusted HR 1.78 95% CI 1.49-2.12). Compared with patients with the lowest quartile (< 0.15) of NAR levels, the risk of long-term mortality in the other groups was higher (0.15-0.20: adjusted HR 1.30 95% CI 0.97-1.73; 0.20-0.28: adjusted HR 1.37 95% CI 1.03-1.82; >0.28: adjusted HR 1.74 95% CI 1.30-2.32). Results in survivors were found to be still robust. Moreover, out of all the inflammatory markers studied, NAR demonstrated the highest correlation with long-term mortality.

CONCLUSIONS

A high level of NAR was associated with increased long-term mortality among patients with aSAH. NAR was a promising inflammatory marker for long-term mortality of aSAH.

Development and external validation of a nomogram for predicting postoperative pneumonia in aneurysmal subarachnoid hemorrhage

Background

Postoperative pneumonia (POP) is a common complication after aneurysmal subarachnoid hemorrhage (aSAH) associated with increased mortality rates, prolonged hospitalization, and high medical costs. It is currently understood that identifying pneumonia early and implementing aggressive treatment can significantly improve patients' outcomes. The primary objective of this study was to explore risk factors and develop a logistic regression model that assesses the risks of POP.

Methods

An internal cohort of 613 inpatients with aSAH who underwent surgery at the Neurosurgical Department of First Affiliated Hospital of Wenzhou Medical University was retrospectively analyzed to develop a nomogram for predicting POP. We assessed the discriminative power, accuracy, and clinical validity of the predictions by using the area under the receiver operating characteristic curve (AUC), the calibration curve, and decision curve analysis (DCA). The final model was validated using an external validation set of 97 samples from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database.

Results

Among patients in our internal cohort, 15.66% (n = 96/613) of patients had POP. The least absolute shrinkage and selection operator (LASSO) regression analysis identified the Glasgow Coma Scale (GCS), mechanical ventilation time (MVT), albumin, C-reactive protein (CRP), smoking, and delayed cerebral ischemia (DCI) as potential predictors of POP. We then used multivariable logistic regression analysis to evaluate the effects of these predictors and create a final model. Eighty percentage of patients in the internal cohort were randomly assigned to the training set for model development, while the remaining 20% of patients were allocated to the internal validation set. The AUC values for the training, internal, and external validation sets were 0.914, 0.856, and 0.851, and the corresponding Brier scores were 0.084, 0.098, and 0.143, respectively.

Conclusion

We found that GCS, MVT, albumin, CRP, smoking, and DCI are independent predictors for the development of POP in patients with aSAH. Overall, our nomogram represents a reliable and convenient approach to predict POP in the patient population.

Pre-operative prognostic nutrition index and post-operative pneumonia in aneurysmal subarachnoid hemorrhage patients

Background and objective

Post-operative pneumonia (POP), a common complication, may be associated with prolonged hospitalization and long-term mortality in aneurysmal subarachnoid hemorrhage (aSAH) patients. This study aimed to explore the association between pre-operative prognostic nutrition index (PNI) and POP in aSAH patients.

Methods

A total of 280 aSAH patients were enrolled from Nanjing Drum Tower Hospital. PNI was calculated as follows: [10 × albumin(gr/dl)] + [0.005 × absolute pre-operative lymphocyte count (per mm³)]. We utilized multivariate analyses, restricted cubic spline, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) to elucidate the role of PNI in POP.

Results

Pre-operative PNI levels in the POP group were higher, compared with the non-POP group (41.0 [39.0, 45.4] vs. 44.4 [40.5, 47.3], P = 0.001). When we included PNI as a categorical variable in the multivariate analysis, the levels of PNI were associated with POP (odds ratio, 0.433; 95% confidence interval, 0.253-0.743; P=0.002). In addition, when we included PNI as a continuous variable in the multivariate analysis, the PNI levels were also associated with POP (odds ratio, 0.942; 95% confidence interval, 0.892-0.994; P = 0.028). The level of albumin was also a predictor of the occurrence of POP, with a lower diagnostic power than PNI [AUC: 0.611 (95% confidence interval, 0.549-0.682; P = 0.001) for PNI vs. 0.584 (95% confidence interval, 0.517-0.650; P = 0.017) for albumin]. Multivariable-adjusted spline regression indicated a linear dose-response association between PNI and POP in aSAH participants (P for linearity = 0.027; P for non-linearity = 0.130). Reclassification assessed by IDI and NRI was significantly improved with the addition of PNI to the conventional model of POP in aSAH patients (NRI: 0.322 [0.089-0.555], P = 0.007; IDI: 0.016 [0.001-0.031], P = 0.040).

Conclusion

The lower levels of pre-operative PNI may be associated with the higher incidence of POP in aSAH patients. Neurosurgeons are supposed to pay more attention to pre-operative nutrition status in aSAH patients.

Predictive Values of White Blood Cell Count in Peripheral Blood at Admission on In-Hospital Complications and 90-Day Outcomes of Patients with Aneurysmal Subarachnoid Hemorrhage: Insights from the LongTEAM Registry

PURPOSE

This study aimed to explore the relationship between white blood cells (WBCs) at admission and clinical outcomes in patients with aneurysmal subarachnoid hemorrhage (aSAH).

PATIENTS AND METHODS

We analyzed data from patients with aSAH between January 2015 and September 2021 who were included in the LongTEAM (Long-term Prognosis of Emergency Aneurysmal Subarachnoid Hemorrhage) registry study. WBC is classified into four groups according to the quartile. We used the logistic model for in-hospital complications, mortality, modified Rankin scale (mRS) at discharge and 90 days to examine the relationship between WBC and clinical outcomes. We used WBC levels near odds ratio (OR) = 1 (Q1) in restricted cubic splines as the reference to evaluate whether there is a nonlinear relationship between WBC and clinical outcomes. Another Kaplan-Meier method was used to analyze the relationship between WBC levels and the risk of developing pneumonia.

RESULTS

Of the 988 patients included, the results showed that compared with patients in the Q1 group, patients in the highest quartile (Q4) had an increased incidence of 90-day unfavorable outcomes after adjusting the confounders (adjusted OR = 1.81, 95% CI = 1.02-3.20, p = 0.042), which may be caused by the increased incidence and risk of pneumonia (adjusted OR = 2.06, 95% CI = 1.30-3.29, p = 0.002; adjusted hazard ratio [HR]=1.63, 95% CI = 1.13-2.36, p < 0.001). The restricted cubic spline indicated that the incidence of developing pneumonia and 90-day unfavorable outcomes rises with increasing WBC levels (p for nonlinear = 0.135 and 0.113).

CONCLUSION

Patients with higher WBC at admission were associated with an increased incidence of 90-day unfavorable outcomes, which might be related to pneumonia.