The impact of lymphopenia on delirium in ICU patients

Piperacillin-Tazobactam Versus Anti-Pseudomonal Cephalosporins and Renal and Neurologic Outcomes in Critically Ill Adults: A Secondary Analysis of the SMART Trial

Background: Prior studies suggest associations between receipt of piperacillin-tazobactam and development of acute kidney injury and receipt of anti-pseudomonal cephalosporins and neurotoxicity. We compared clinically-relevant renal and neurologic outcomes in critically ill patients who received piperacillin-tazobactam versus anti-pseudomonal cephalosporins. Methods: We conducted a secondary analysis of data from the Isotonic Solutions and Major Adverse Renal Events Trial examining patients who received piperacillin-tazobactam or an anti-pseudomonal cephalosporin within 24 h of intensive care unit admission. We performed multivariable analysis using a proportional odds model to examine the association between the first antibiotic received and the outcomes of Major Adverse Kidney Events within 30 days (MAKE30) and days alive and free of delirium and coma to day 28. Results: 3199 were included in the study; 2375 (74%) receiving piperacillin-tazobactam and 824 (26%) receiving anti-pseudomonal cephalosporin. After adjustment for prespecified confounders, initial receipt of piperacillin-tazobactam, compared to anti-pseudomonal cephalosporins, was not associated with higher incidence of MAKE30 (adjusted odds ratio, 1.03; 95% CI, 0.83-1.27; P = .80) but was associated with a greater number of days alive and free of delirium and coma (adjusted odds ratio, 1.18; 95% CI, 1.00-1.38; P = .04). In a sensitivity analysis adjusting for baseline receipt of medications which may impact neuro function, this finding was not significant. Conclusion: Among critically ill adults, receipt of piperacillin-tazobactam was not associated with an increased incidence of death, renal replacement therapy, or persistent renal dysfunction or a greater number of days alive and free of delirium and coma. Randomized trials are needed to inform the choice of antibiotics for empiric treatment infection in critically ill adults.

The role of inflammatory parameters in the prediction of postoperative delirium in patients undergoing coronary artery bypass grafting

OBJECTIVE

In this study, we aimed to evaluate the association of pre-operative and early postoperative inflammatory parameters with postoperative delirium in patients operated on for coronary artery bypass grafting.

METHODS

The data of 1 279 cardiac surgery patients operated on between June 2014 and March 2020 were analysed retrospectively. Among these, 777 (61.2%) patients operated on for isolated coronary artery bypass grafting surgery with cardiopulmonary bypass were enrolled. Two groups were formed. The patients who developed postoperative delirium were placed in group 1 (n = 187) and the patients with uneventful postoperative follow up (n = 590) were enrolled in group 2.

RESULTS

Pre- and early postoperative mean platelet volume, C-reactive protein level, erythrocyte sedimentation rate, platelet- to-lymphocyte ratio and neutrophil-to-lymphocyte ratio were elevated in group 1 (p = 0.0001). The APACHE II score and duration of hospital and intensive care unit stay were significantly elevated in group 1 (p < 0.05). An early-stage neurological event was observed in eight patients (4.3%) in group 1 and 12 patients (2%) in group 2, which was not statistically significantly different between the groups (p = 0.09). In-hospital mortality was observed in three patients (1.6%) in group 1 and five patients (0.8%) in group 2, which did not show a statistically significant difference (p > 0.05). In univariate and multivariate regression analysis, the pre-operative platelet-to-lymphocyte ratio (p = 0.013), mean platelet volume (p = 0.0001) and erythrocyte sedimentation rate (p = 0.002) were determined as independent risk factors for the occurrence of delirium in the early postoperative period. Also, the postoperative platelet-to-lymphocyte ratio (p = 0.0001), neutrophil-to-lymphocyte ratio (p = 0.0001) and erythrocyte sedimentation rate (p = 0.0001) were determined as independent risk factors for the occurrence of delirium in the early postoperative period.

CONCLUSIONS

Pre- and early postoperative inflammatory parameters were observed to be predictors of postoperative delirium in patients operated on for coronary artery bypass grafting.

Neutrophil-lymphocyte ratio as a predictor of delirium in older internal medicine patients: a prospective cohort study

BACKGROUNDS

Delirium is a common neuropsychiatric syndrome in older hospitalized patients. Previous studies have suggested that inflammation and oxidative stress contribute to the pathophysiology of delirium. However, it remains unclear whether neutrophil-lymphocyte ratio (NLR), an indicator of systematic inflammation, is associated with delirium. This study aimed to investigate the value of NLR as an independent risk factor for delirium among older hospitalized patients.

METHODS

We conducted a prospective study of 740 hospitalized patients aged ≥ 70 years in the geriatric ward of West China Hospital of Sichuan University. Neutrophil and lymphocyte counts were collected within 24 h after hospital admission. Delirium was assessed on admission and every 48 h thereafter. We used the receiver operating characteristic analysis to assess the ability of the NLR for predicting delirium. The optimal cut-point value of the NLR was determined based on the highest Youden index (sensitivity + specificity - 1). Patients were categorized according to the cut-point value and quartiles of NLR, respectively. We then used logistic regression to identify the unadjusted and adjusted associations between NLR as a categorical variable and delirium.

RESULTS

The optimal cut-point value of NLR for predicting delirium was 3.626 (sensitivity: 75.2 %; specificity: 63.4 %; Youden index: 0.386). The incidence of delirium was significantly higher in patients with NLR > 3.626 than NLR ≤ 3.626 (24.5 % vs. 5.8 %; P < 0.001). Significantly fewer patients in the first quartile of NLR experienced delirium than in the third (4.3 % vs. 20.0 %; P < 0.001) and fourth quartiles of NLR (4.3 % vs. 24.9 %; P < 0.001). Results from the multivariable logistic regression models showed that NLR was independently associated with delirium.

CONCLUSIONS

NLR is a simple and practical marker that can predict the development of delirium in older internal medicine patients.

Cardiac Delirium Index for Predicting the Occurrence of Postoperative Delirium in Adult Patients After Coronary Artery Bypass Grafting

Background

Postoperative delirium (POD) is a serious complication of cardiac surgery. It is an acute neuropsychiatric syndrome. The aim of this study was to analyze the CARDEL Index, composed of advancing age, preoperative glycated hemoglobin and the platelet-to-WBC ratio (PWR) previously described and calculated, using a different patient database, to assess its usefulness as a marker for predicting postoperative delirium after coronary artery by-pass grafting (CABG).

Methods

A retrospective analysis of 1098 patients who underwent, isolated CABG procedures between 2017 and 2019 was performed.

Results

Within the study group, 164/1098 (14.93%) patients were diagnosed with delirium. Preoperative inflammatory parameters were elevated in patients with delirium: White Blood Cell count (p=0.003), Neutrophil count (p=0.016) and C-reactive protein (p<0.001). A decrease in preoperative PWR was shown in patients with delirium (p=0.008). Delirious patients spent more time mechanically ventilated (p<0.001) and had longer hospitalization times (p=0.002). Mortality at 1 year was significantly higher in patients with POD (p<0.001). The CARDEL Index in this study group for POD detection has the largest area under the curve (AUC) of 0.664 (p<0.001) and a cut-off value of 8.08.

Conclusion

CARDEL Index may be treated as a potentially valuable tool for delirium prediction in patients after CABG.

Lymphocyte and NK Cell Counts Can Predict Sepsis-Associated Delirium in Elderly Patients

Background: Sepsis-associated delirium (SAD) is prevalent in elderly patients and is recognized as brain dysfunction associated with increased inflammatory response in the central nervous system during sepsis. Neuroinflammation was demonstrated to be part of its mechanism and we aimed to validate the role of immunity imbalance in a combined retrospective and prospective cohort study.

Methods: We performed a retrospective study analyzing the association between SAD and lymphocyte counts in the peripheral blood, alongside a prospective trial evaluating the quantitative changes in lymphocyte subsets and their predictive value for early diagnosis of SAD.

Results: In the retrospective study, among 1,010 enrolled adult patients (age ≥65 years), 297 patients were diagnosed with delirium during intensive care unit (ICU) stay and lymphocyte counts at ICU admission in the SAD group were significantly higher than in non-delirious counterparts (1.09 ± 0.32 vs. 0.82 ± 0.24, respectively, p = 0.001). In the prospective study, lymphocyte counts [0.83 (0.56, 1.15) vs. 0.72 (0.40, 1.06) × 10⁹/L, p = 0.020] and natural killer (NK) cell counts [96 (68, 118) vs. 56 (26, 92) cells/μl, p = 0.024] were significantly higher in the SAD group. The area under the curve value of NK cell count was 0.895 [95% confidence interval (CI): 0.857, 0.933] and of lymphocyte count was 0.728 (95% CI: 0.662, 0.795). An NK cell count cut-off value of 87 cells/ml in septic patients at ICU admission was predictive of delirium with a sensitivity of 80.2% and specificity of 80.8%.

Conclusions: We found that lymphocyte and NK cell counts were significantly higher in senior patients with SAD and that NK cell count may be valuable for the prediction of SAD within elderly patient cohorts.

The Practical Use of White Cell Inflammatory Biomarkers in Prediction of Postoperative Delirium after Cardiac Surgery

: Introduction: Postoperative delirium (POD) is associated with unfavorable outcomes. It may result from neuroinflammation and oxidative stress. The aim of this study was to evaluate the role of routinely available inflammatory markers derived from white blood cell count (WBC), for prognostic value in diagnosing delirium after cardiac surgery.

METHODS

We performed an analysis of data collected from patients undergoing planned coronary artery bypass grafting (CABG). Differential WBC and CRP concentration were evaluated preoperatively (T0) and postoperatively at day 1 (T1), 3 (T3), 5 (T5) after CABG. Differences in neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and platelet-to-WBC ratio (PWR) between patients with (Del+) and without delirium (Del-) were evaluated. Patients were screened using CAM-ICU.

RESULTS

We included 968 patients in the study. Incidence of delirium was 13.3%. In the group with POD, the majority of patients were men (87/129, 67.44%), and the mean age was 72 years. Preoperative WBC (8.21 ± 3.04 G/l vs. 7.55 ± 1.86 G/l, p = 0.029) were higher and mean platelet count was lower (217.7 ± 69.07 G/l vs. 227.44 ± 59.31 G/l, p = 0.031) in patients with POD. Lower pre-operative PLR values (109.87 ± 46.38 vs. 120.36 ± 52.98, p = 0.026) and PWR values (27.69 7.50 vs. 31.32 9.88 p < 0.001) were found in patients with POD. Association was strongest for PWR and remained significant at T1 (p < 0.001), T3 (p < 0.001) and T5 (p < 0.001). Basing on coefficients of logistic regression a model for optimal prediction of POD was calculated: CARDEL Index = 0.108 × Age + 0.341 × HBA1C - 0.049 × PWR with AUC of 0.742 (p < 0.001).

CONCLUSIONS

The results of this study show that lower pre-operative levels of PLR and PWR were associated with POD after cardiac surgery. Pre-operative PWR showed strongest correlation with POD and may be a potential new biomarker associated with postoperative delirium. CARDEL prognosis index composed of age, HbA1c and PWR is good at predicting development of delirium after CABG.

Could Neutrophil-to-Lymphocyte Ratio (NLR) Serve as a Potential Marker for Delirium Prediction in Patients with Acute Ischemic Stroke? A Prospective Observational Study

Delirium is an acute brain disorder that commonly occurs in patients with acute ischemic stroke (AIS). Pathomechanism of delirium is related to the neuroinflammatory process and oxidative stress. Search for readily available diagnostic marker that will aid clinicians in early identification of delirium is ongoing. The aim of this study was to investigate whether neutrophil-to-lymphocyte ratio (NLR) could serve as a potential marker for delirium prediction in patients with AIS and to find an easy diagnostic tool using laboratory and clinical parameters to predict delirium. Prospective observational study (NCT03944694) included patients with AIS admitted to the neurology department of a district general hospital. All patients were screened for delirium using CAM-ICU (Confusion Assessment Method for Intensive Care Unit). Demographic and medical history data and admission lab results, including differential white blood cell analysis, were collected from all patients. We included 1001 patients in the final analysis. The mean age of the sample was 71 years, and 52% of patients were males. The incidence of early-onset delirium was 17.2%. The NLR was elevated in delirious patients (6.39 ± 8.60 vs. 4.61 ± 5.61, p < 0.001). The best cut-off value of NLR to predict delirium using the receiver operating characteristics (ROC) was determined at 4.86. Multivariable logistic regression analysis showed that the odds ratio (OR) for developing delirium with NLR > 4.86 (adjusted for age, sex, body mass index (BMI), comorbidities, and baseline neurology) was 1.875 (95% CI 1.314-2.675, p = 0.001). As a result of different combinations of markers and clinical parameters based on logistic regression, a formula-DELirium in Acute Ischemic Stroke (DELIAS score)-was obtained with the area under the ROC curve of 0.801 (p < 0.001). After regression of the cut-off points of the obtained curve, a significant correlation of the DELIAS score was observed with the occurrence of early-onset delirium (OR = 8.976, p < 0.001) and with delirium until the fifth day after AIS (OR = 7.744, p < 0.001). In conclusion, NLR can be regarded as a potential marker for prediction of early-onset delirium after AIS. On the basis of combined laboratory and clinical parameters, the DELIAS score was calculated, which gave the highest predictive value for delirium in the analyzed group of patients after ischemic stroke. However, further studies are needed to validate these findings.

Type D personality is a predictor of prolonged acute brain dysfunction (delirium/coma) after cardiovascular surgery

BACKGROUND

Previous studies have shown a relationship between delirium and depressive symptoms after cardiac surgery with distress personalities linking to negative surgical outcomes. The aim of the present study is to further investigate the association between patients with Type D (distressed) personality with regards to delirium after cardiac surgery.

METHODS

We conducted a consecutive-sample observational cohort pilot study with an estimated 142 patients needed. Enrollment criteria included patients aged ≥18 years who were undergoing planned cardiovascular, thoracic and abdominal artery surgery between October 2015 to August 2016 at the University of Tsukuba Hospital, Japan. All patients were screened by Type-D Personality Scale-14 (DS14) as well as the Hospital Anxiety and Depression Scale (HADS) the day before surgery. Following surgery, daily data was collected during recovery and included severity of organ dysfunction, sedative/analgesic exposure and other relevant information. We then evaluated the association between Type D personality and delirium/coma days (DCDs) during the 7-day study period. We applied regression and mediation modeling for this study.

RESULTS

A total of 142 patients were enrolled in the present study and the total prevalence of delirium was found to be 34% and 26% of the patients were Type D. Non-Type D personality patients experienced an average of 1.3 DCDs during the week after surgery while Type D patients experienced 2.1 days over the week after surgery. Multivariate analysis showed that Type D personality was significantly associated with increased DCDs (OR:2.8, 95%CI:1.3-6.1) after adjustment for depressive symptoms and clinical variables. Additionally, there was a significant Type D x depression interaction effect (OR:1.7, 95% CI:1.2-2.2), and depressive symptoms were associated with DCDs in Type D patients, but not in non-Type D patients. Mediation modeling showed that depressive symptoms partially mediated the association of Type D personality with DCDs (Aroian test =0.04).

CONCLUSIONS

Type D personality is a prognostic predictor for prolonged acute brain dysfunction (delirium/coma) in cardiovascular patients independent from depressive symptoms and Type D personality-associated depressive symptoms increase the magnitude of acute brain dysfunction.

Increased neutrophil-lymphocyte ratio in delirium: a pilot study

Aim

Delirium is a common and severe complication among older hospitalized patients. The pathophysiology is poorly understood, but it has been suggested that inflammation and oxidative stress may play a role. The aim of this pilot study was to investigate levels of the neutrophil–lymphocyte ratio (NLR) – a marker of systemic inflammation and oxidative stress – in patients with and without delirium.

Methods

This pilot study was performed within a retrospective chart review study that included acutely ill patients, 65 years and older, who were admitted to the ward of geriatrics of the Erasmus University Medical Center. All patients in whom the differential white blood cell (WBC) counts as well as the C-reactive protein (CRP) level were determined within 24 h after admission were included in the present study. Differences in NLR between patients with and without delirium were investigated using univariate analysis of variance, with adjustments for age, sex, comorbidities, CRP level, and total WBC count.

Results

Eighty-six patients were included. Thirteen patients were diagnosed with delirium. In adjusted models, higher mean NLR values were found in patients with, than in those without, delirium (9.10 vs 5.18, P=0.003).

Conclusion

In this pilot study, we found increased NLR levels in patients with delirium. This finding might suggest that an inadequate response of the immune system and oxidative stress may play a role in the pathogenesis of delirium. Further studies are needed to confirm the association between NLR and delirium.