Reduced butyrylcholinesterase activity is an early indicator of trauma-induced acute systemic inflammatory response

Exploring the Potential Role of the Cholinergic Anti-Inflammatory Pathway from the Perspective of Sepsis Pathophysiology

Sepsis is one of the most prevalent conditions in critical care medicine and is characterized by a high incidence, mortality, and poor prognosis, with no specific treatment currently available. The pathogenesis of sepsis is complex with a dysregulated inflammatory response at its core. If the initial inflammatory response is not promptly controlled, patients often develop multiple organ dysfunction syndrome or die, whereas survivors may experience post-sepsis syndrome. Regulation by the central and autonomic nervous systems is essential for maintaining inflammatory homeostasis. Among these, the cholinergic anti-inflammatory pathway (CAP) has been extensively studied in sepsis owing to its significant role in modulating inflammatory responses. Recent advancements in CAP-related interventions include minimally invasive vagus nerve stimulation, novel α7nAchR-targeting drugs, serum choline acetyltransferase and cholinesterase, acupuncture, and focused ultrasound stimulation therapy. This review primarily discusses the advantages, limitations, and therapeutic prospects of these approaches. Additionally, heart rate variability, which reflects changes in autonomic nervous system function, can serve as an indicator for assessing the functional status of the vagus nerve. In summary, modulation of inflammatory responses through the vagus nerve-mediated CAP represents a potential strategy for achieving precision medicine for sepsis. Future research should focus on conducting high-quality clinical studies on CAP-based therapies in the context of sepsis-induced inflammatory dysregulation. Incorporating indicators to evaluate the autonomic nervous system function may further elucidate the impact of inflammatory dysregulation in the body.

Modification in ICU design may influence circadian serum cholinesterase activities: a proof-of-concept pilot study

BACKGROUND

Deficits in cholinergic function are assumed to cause cognitive decline. Studies have demonstrated that changes in serum cholinesterase activities are associated with a higher incidence of delirium in critically ill patients. Additionally, basic research indicates that the cholinergic and circadian systems are interconnected, with each system influencing the functionality of the other. This data analysis of a proof-of-concept pilot study investigates whether modification in ICU design, including dynamic light therapy, may influence the circadian oscillation of serum cholinesterase activities.

METHODS

We enrolled adult critically ill patients who were on mechanical ventilation and had an anticipated ICU stay of at least 48 h. The patients were treated in either modified or standard ICU rooms. The modified rooms received extensive architectural modifications, including a new dynamic lighting system. Serum acetylcholinesterase and butyrylcholinesterase activities were measured every four hours for up to three 24-h assessment periods.

RESULTS

We included 64 patients in the data analysis (n = 34 patients in modified rooms, n = 30 in standard rooms). The median values of serum acetylcholinesterase and butyrylcholinesterase activities showed different patterns. Acetylcholinesterase activities differed significantly between the groups during the first assessment period (p = 0.04) and the second assessment period (p = 0.045). The intensity of light, as quantified by the effective circadian irradiance, significantly influenced the activities of acetylcholinesterase and butyrylcholinesterase throughout all assessment periods for patients in both groups (p < 0.001). The analysis showed significant interaction (p < 0.001), indicating that the differences in acetylcholinesterase and butyrylcholinesterase activities between the groups were inconsistent over time but apparent during specific periods of the day.

CONCLUSION

Implementing a comprehensive set of changes to the design of ICU rooms, including a dynamic lighting system, may influence the course of the activity patterns of acetylcholinesterase and butyrylcholinesterase in critically ill patients. Modifications to environmental factors could potentially offer neuroprotective benefits and facilitate the realignment of circadian rhythms within the cholinergic system. Clinical trial registration ClinicalTrials.gov: NCT02143661. Registered May 21, 2014.

Systemic Immune-Inflammation Index and Systemic Inflammation Response Index Predict the Response to Radioiodine Therapy for Differentiated Thyroid Cancer

Purpose

This research sought to evaluate the clinical value of systemic immune-inflammation index and systemic inflammation response index in predicting the response to radioactive iodine (RAI) therapy in individuals diagnosed with differentiated thyroid cancer.

Patients and Methods

This retrospective study included 406 patients with differentiated thyroid cancer who received initial RAI therapy and follow-up from December 2019 to December 2023. Patients were divided into two groups based on imaging and serum indicators to evaluate the response to radioactive iodine treatment: the ER group (excellent response) and the non-ER group (suboptimal response). Systemic immune-inflammation index and systemic inflammation response index were calculated based on peripheral blood cell counts before treatment. Multivariable logistic regression analysis was used to assess the independent associations of these indices with the therapeutic response to radioiodine treatment. Receiver operating characteristic (ROC) curves were graphed and the area under the curve (AUC) was calculated to evaluate their predictive ability.

Results

Compared to the ER group, patients in the non-ER group had significantly elevated systemic immune-inflammation index and systemic inflammation response index levels (p < 0.001). After adjusting for confounding factors, there was a significant association between these indices and the response to radioactive iodine treatment in patients with differentiated thyroid cancer. The optimal cutoff values for predicting the response to RAI treatment were 668.91 for systemic immune-inflammation index (AUC=0.692, sensitivity 58.2%, specificity 73.1%, 95% CI: 0.639-0.745, p < 0.001) and 0.47 for systemic inflammation response index (AUC=0.664, sensitivity 85.6%, specificity 42.7%, 95% CI: 0.612-0.717, p < 0.001).

Conclusion

Systemic immune-inflammation index and systemic inflammation response index could be valuable for predicting the response to RAI treatment in individuals diagnosed with differentiated thyroid cancer. Further research is needed to explore their practical utility, and these novel inflammation markers could serve as adjunct tools in clinical practice.

Butyrylcholinesterase levels correlate with surgical site infection risk and severity after colorectal surgery: a prospective single-center study

INTRODUCTION

Surgical site infections (SSIs) after colorectal surgery remain a significant concern, which warrants effective predictive markers for prompt diagnosis and treatment. Butyrylcholinesterase (BChE), a non-specific cholinesterase enzyme, has been correlated with the risk of hepatic dysfunction progression and, more recently, infectious diseases and septic shock with ongoing research into the utility of BChE in multiple systemic inflammatory conditions. Whether these preliminary results can be translated into predicting infection after colorectal surgery remains in remains in question. This prospective study aimed to assess BChE's potential as a predictive marker for surgical site infections and anastomotic leaks after colorectal surgery.

MATERIALS AND METHODS

This single-center prospective study (11/2019-05/2023) enrolled 402 patients who underwent colorectal surgery. BChE levels were measured at four postoperative time points. The primary endpoints focused on BChE's association with complications, particularly surgical site infections (SSIs). Further known predictors of SSI were utilized to construct multivariable models to assess for independent association with SSI development.

RESULTS

During the third and fifth day postsurgery, SSI patients had significantly lower mean BChE levels (3.90 KU/L vs. 4.54 KU/L p-value < 0.05, and 4.14 KU/L vs. 4.73 KU/L, p-value < 0.05; t-test, respectively). However, multivariate analysis revealed that when adjusted for other factors, low BChE levels on the first postoperative day were associated with 2.6 times higher odds of developing SSI (OR: 2.6, 95%CI: 1.3-3.9, p-value < 0.05). Similar results were found for low BChE levels on the third postoperative day as they were associated with a. 2.53 times higher odds for developing SSI (OR: 2.5, 95%CI: 1.27-3.87, p-value < 0.05) when adjusted for other factors.

CONCLUSION

In conclusion, in this prospective observational study, low levels in the first and third postsurgery were associated with an increased risk for the development of SSIs but not sepsis.

Butyrylcholinesterase activity in patients with postoperative delirium after cardiothoracic surgery or percutaneous valve replacement- an observational interdisciplinary cohort study

BACKGROUND AND OBJECTIVES

Postoperative delirium is a frequent and severe complication after cardiac surgery. Activity of butyrylcholinesterase (BChE) has been discussed controversially regarding a possible role in its development. This study aimed to investigate the relevance of BChE activity as a biomarker for postoperative delirium after cardiac surgery or percutaneous valve replacement.

METHODS

A total of 237 patients who received elective cardiothoracic surgery or percutaneous valve replacement at a tertiary care centre were admitted preoperatively. These patients were tested with the Montreal Cognitive Assessment investigating cognitive deficits, and assessed for postoperative delirium twice daily for three days via the 3D-CAM or the CAM-ICU, depending on their level of consciousness. BChE activity was measured at three defined time points before and after surgery.

RESULTS

Postoperative delirium occurred in 39.7% of patients (n = 94). Univariate analysis showed an association of pre- and postoperative BChE activity with its occurrence (p = 0.037, p = 0.001). There was no association of postoperative delirium and the decline in BChE activity (pre- to postoperative, p = 0.327). Multivariable analysis including either preoperative or postoperative BChE activity as well as age, MoCA, type 2 diabetes mellitus, coronary heart disease, type of surgery and intraoperative administration of red-cell concentrates was performed. Neither preoperative nor postoperative BChE activity was independently associated with the occurrence of postoperative delirium (p = 0.086, p = 0.484). Preoperative BChE activity was lower in older patients (B = -12.38 (95% CI: -21.94 to -2.83), p = 0.011), and in those with a history of stroke (B = -516.173 (95% CI: -893.927 to -138.420), p = 0.008) or alcohol abuse (B = -451.47 (95% CI: -868.38 to -34.55), p = 0.034). Lower postoperative BChE activity was independently associated with longer procedures (B = -461.90 (95% CI: -166.34 to -757.46), p = 0.002), use of cardiopulmonary bypass (B = -262.04 (95% CI: -485.68 to -38.39), p = 0.022), the number of administered red cell-concentrates (B = -40.99 (95% CI: -67.86 to -14.12), p = 0.003) and older age (B = -9.35 (95% CI: -16.04 to -2.66), p = 0.006).

CONCLUSION

BChE activity is not independently associated with the occurrence of postoperative delirium. Preoperative BChE values are related to patients' morbidity and vulnerability, while postoperative activities reflect the severity, length and complications of surgery.

Cholinesterase activities and sepsis-associated encephalopathy in viral versus nonviral sepsis

PURPOSE

There is evidence that cholinergic imbalance secondary to neuroinflammation plays a role in the pathophysiology of sepsis-associated encephalopathy (SAE). Blood acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities have been proposed as surrogate parameters for the cholinergic function of the central nervous system. Viral sepsis is associated with systemic inflammation and BChE has been reported to be of prognostic value in a small cohort of COVID-19 patients. Nevertheless, the prognostic value of AChE in patients with viral sepsis remains unclear.

METHODS

We investigated the role of AChE and BChE activities as prognostic biomarkers of SAE and mortality in patients with viral vs nonviral sepsis enrolled in two prospective cohort studies. We quantified the AChE and BChE activities in whole blood of patients at two time points in the acute phase of viral sepsis (N = 108) and compared them with the activities in patients with nonviral sepsis (N = 117) and healthy volunteers (N = 81). Patients were observed until discharge from the intensive care unit (ICU).

RESULTS

Three days after sepsis onset, the median [interquartile range] levels of AChE and BChE were reduced in both patients with viral sepsis (AChE, 5,105 [4,010-6,250] U·L-1; BChE, 1,943 [1,393-2,468] U·L-1) and nonviral sepsis (AChE, 4,424 [3,630-5,055] U·L-1; BChE, 1,095 [834-1,526] U·L-1) compared with healthy volunteers (AChE, 6,693 [5,401-8,020] U·L-1; BChE, 2,645 [2,198-3,478] U·L-1). Patients with viral sepsis with SAE during their ICU stay had lower AChE activity three days after sepsis onset than patients without SAE (4,249 [3,798-5,351] U·L-1 vs 5,544 [4,124-6,461] U·L-1). Butyrylcholinesterase activity seven days after sepsis onset was lower in patients with viral sepsis who died in the ICU than in surviving patients (1,427 [865-2,181] U·L-1 vs 2,122 [1,571-2,787] U·L-1).

CONCLUSION

Cholinesterase activities may be relevant prognostic markers for the occurrence of SAE and mortality in the ICU in patients with viral sepsis.

STUDY REGISTRATION

This study constitutes an analysis of data from the ongoing studies ICROS (NCT03620409, first submitted 15 May 2018) and ICROVID (DRKS00024162, first submitted 9 February 2021).

Prognostic Value of Serum Cholinesterase Levels for In-Hospital Mortality among Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Cholinesterase (ChE) is associated with the pathogenesis of chronic obstructive pulmonary disease (COPD), including chronic airway inflammation and oxidation/antioxidant imbalance. However, the relationship between serum ChE levels and survival outcomes of patients hospitalized with acute exacerbations of COPD (AECOPD) is unknown. In this retrospective single-center study, we investigated the ability of the serum ChE level to predict in-hospital death in patients hospitalized with AECOPD. The clinicopathological data, including serum ChE levels as well as clinical and biochemical indicators were extracted for 477 patients from the hospital records and analyzed. Our results demonstrated that AECOPD patients with lower serum ChE levels were associated with increased mortality, frequent hospitalization due to acute exacerbations (AE) in the past year, and longer hospital stay. The optimal cutoff value for the serum ChE level was 4323 U/L. The area under the ROC curve (AUC) values for predicting in-hospital mortality based on the serum ChE level was 0.79 (95% confidence interval (CI), 0.72-0.85). Multivariate logistic regression analysis demonstrated that serum ChE level ≤ 4323 U/L (odds ratio (OR) 9.09, 95% CI 3.43-28.3, p < 0.001), age-adjusted Charlson comorbidity index (aCCI), and the number of hospitalizations due to AE in the past year were independent risk factors for predicting the in-hospital mortality of AECOPD patients. In conclusion, our study demonstrated that low serum ChE levels were associated with significantly higher in-hospital mortality rates of patients hospitalized with AECOPD. Therefore, serum ChE level is a promising prognostic predictor of hospitalized AECOPD patients.

Potentials of Acetylcholinesterase and Butyrylcholinesterase Alterations in On-Pump Coronary Artery Bypass Surgery in Postoperative Delirium: An Observational Trial

Cardiac surgery is regularly associated with postoperative delirium (POD), affected by neuro-inflammation and changes in cholinergic activity. Therefore, this prospective observational study aimed to evaluate whether pre- and perioperative changes in blood acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity were associated with POD development in patients undergoing isolated elective coronary artery bypass graft (CABG) surgery. It included 93 patients. Pre- and postoperative blood AChE and BChE activities were measured with photometric rapid-point-of-care-testing. The Intensive Care Delirium Screening Checklist and the Confusion Assessment Method for the Intensive Care Unit were used to screen patients for POD. POD developed in 20 patients (21.5%), who were older (p = 0.003), had higher EuroSCOREs (p ≤ 0.001), and had longer intensive care unit stays (p < 0.001). On postoperative day one, BChE activity decreased from preoperative values more in patients with (31.9%) than without (23.7%) POD (group difference p = 0.002). Applying a cutoff of ≥32.0% for BChE activity changes, receiver operating characteristic analysis demonstrated a moderate prediction capability for POD (area under the curve = 0.72, p = 0.002). The risk of developing POD was 4.31 times higher with a BChE activity change of ≥32.0% (p = 0.010). Monitoring the pre- to postoperative reduction in BChE activity might be a clinically practicable biomarker for detecting patients at risk of developing POD after CABG surgery.

Non-Neuronal Acetylcholinesterase Activity Shows Limited Utility for Early Detection of Sepsis

(1) Background: Sepsis is a severe systemic inflammatory condition characterized by rapid clinical deterioration and organ dysfunction. The cholinergic system has been implicated in modulating the inflammatory response. Acetylcholinesterase (AChE), an enzyme primarily responsible for the hydrolysis of acetylcholine, has been proposed as a potential early indicator of sepsis onset. However, the exact role of non-neuronal AChE activity in sepsis and its correlation with disease severity and patient outcomes remain unclear. This study aimed to investigate the involvement of AChE activity in sepsis and evaluate its association with disease severity and clinical outcomes. (2) Methods: A prospective study included 43 septic patients. AChE activity was measured at sepsis detection, as well as 7 and 28 days later. Inflammatory biomarkers, disease severity scores, and patient outcomes were evaluated. (3) Results: AChE activity remained stable for 7 days and decreased at 28 days. However, there was no correlation between initial AChE activity and inflammatory biomarkers, disease severity scores, ICU stay, or hospital stay. (4) Conclusions: Non-neuronal AChE activity may not reliably indicate early sepsis or predict disease severity.

Preoperative BChE serves as a prognostic marker in patients with resectable AEG after neoadjuvant chemotherapy

BACKGROUND

Diminished systemic serum butyrylcholinesterase (BChE), a biomarker for chronic inflammation, cachexia, and advanced tumor stage, has shown to play a prognostic role in various malignancies. The aim of this study was to investigate the prognostic value of pretherapeutic BChE levels in patients with resectable adenocarcinoma of the gastroesophageal junction (AEG), treated with or without neoadjuvant therapy.

METHODS

Data of a consecutive series of patients with resectable AEG at the Department for General Surgery, Medical University of Vienna, were analyzed. Preoperative serum BChE levels were correlated to clinic-pathological parameters as well as treatment response. The prognostic impact of serum BChE levels on disease-free (DFS) and overall survival (OS) was evaluated by univariate and multivariate cox regression analysis, and Kaplan-Meier curves used for illustration.

RESULTS

A total of 319 patients were included in this study, with an overall mean (standard deviation, SD) pretreatment serum BChE level of 6.22 (± 1.91) IU/L. In univariate models, diminished preoperative serum BChE levels were significantly associated with shorter overall (OS, p < 0.003) and disease-free survival (DFS, p < 0.001) in patients who received neoadjuvant treatment and/or primary resection. In multivariated analysis, decreased BChE was significantly associated with shorter DFS (HR: 0.92, 95% CI: 0.84-1.00, p 0.049) and OS (HR: 0.92, 95% CI: 0.85-1.00, p < 0.49) in patients receiving neoadjuvant therapy. Backward regression identified the interaction between preoperative BChE and neoadjuvant chemotherapy as a predictive factor for DFS and OS.

CONCLUSION

Diminished serum BChE serves as a strong, independent, and cost-effective prognostic biomarker for worse outcome in patients with resectable AEG who had received neoadjuvant chemotherapy.

Transcranial direct current stimulation effects in the pain threshold and in oxidative stress parameters of neuropathic pain rats

Transcranial direct current stimulation (tDCS) can modulate cortical excitability and relieve neuropathic pain (NP), but the role of several biomarkers in this process is not well understood. This study aimed to analyze the effects of tDCS on biochemical parameters in rats with neuropathic pain (NP) induced by chronic constriction injury (CCI) of the right sciatic nerve. Eighty-eight male 60-day-old Wistar rats were divided into nine groups: control (C), control-electrode off (CEoff), control-tDCS (C-tDCS), sham-lesion (SL), sham-lesion electrode off (SLEoff), sham-lesion (SL-tDCS), lesion (L), lesion electrode off (LEoff), and lesion-tDCS (L-tDCS). After NP establishment, 20-minute bimodal tDCS for 8 consecutive days was applied to the rats. Fourteen days after the induction of NP, rats developed mechanical hyperalgesia with a decreased threshold, and at the end of treatment, an increase in the pain threshold was observed in NP rats. In addition, NP rats had increased levels of reactive species (RS) in the prefrontal cortex, while superoxide dismutase (SOD) activity was decreased in NP rats. In the spinal cord, nitrite levels and glutathione-S-transferase (GST) activity decreased in the L-tDCS group, and it was observed that increased levels in total sulfhydryl content for neuropathic pain rats were reversed by tDCS. In serum analyses, the neuropathic pain model increased the levels of RS and thiobarbituric acid-reactive substances (TBARS) and decreased the activity of butyrylcholinesterase (BuChE). In conclusion, bimodal tDCS increased total sulfhydryl content in the spinal cord of rats with neuropathic pain, positively modulating this parameter.

Diagnostic and Prognostic Performance of Plasma Albumin and Cholinesterase in Patients with Sepsis and Septic Shock

OBJECTIVE

Despite improved risk stratification tools and identification of novel biomarkers for the diagnosis and prognosis in patients with sepsis, sepsis-related mortality has not significantly improved during the past years. This study investigates the diagnostic and prognostic role of the plasma albumin and cholinesterase (ChE) in patients with sepsis and septic shock.

METHODS

Consecutive patients with sepsis and septic shock from 2019 to 2021 were included at one institution. Blood samples were obtained on the day of disease onset (day 1), and on days 2, 3, 5, and 7 thereafter. The diagnostic value of ChE for the diagnosis of a septic shock was compared to albumin and the prognostic value of the albumin and the ChE for 30-day all-cause mortality was tested.

RESULTS

239 patients were included with a median albumin level of 21.4 g/dL and a median ChE of 5004 U/L on admission. With an area under the curve (AUC) of 0.641-0.762 on days 3 and 5, the ChE was associated with moderate but better diagnostic discrimination between sepsis and septic shock than albumin. Furthermore, ChE was able to discriminate between 30-day non-survivors and survivors (range of AUC 0.612-0.686). Patients with a ChE below the median had higher rates of 30-days all-cause mortality in comparison to patients with a ChE above the median (65 vs. 42%, log rank p = 0.001; HR = 1.820; 95% CI = 1.273-2.601; p = 0.001), which was still demonstrated after multivariable adjustment.

CONCLUSION

The level of ChE was associated with moderate diagnostic and prognostic accuracy in patients with sepsis and septic shock, whereas albumin was not.

In a secondary analysis from a randomised, double-blind placebo-controlled trial Dexmedetomidine blocks cholinergic dysregulation in delirium pathogenesis in patients with major surgery

Dexmedetomidine is an alpha-2 adrenoreceptor agonist with anti-inflammatory and anti-delirogenic properties. Pathogenesis of postoperative delirium (POD) includes cholinergic dysfunction and deregulated inflammatory response to surgical trauma. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are discussed as biomarkers for both POD and severity in acute inflammation. To show whether there is a link between blood cholinesterase activities and dexmedetomidine, we performed a secondary analysis of a randomised, double-blind, placebo-controlled trial that recently showed a lower incidence of POD in the dexmedetomidine group. Abdominal or cardiac surgical patients aged ≥ 60 years were randomised to receive dexmedetomidine or placebo intra- and postoperatively in addition to standard general anaesthesia. We analysed the course of perioperative cholinesterase activities of 56 patients, measured preoperatively and twice postoperatively. Dexmedetomidine resulted in no change in AChE activity and caused a rapid recovery of BChE activity after an initial decrease, while placebo showed a significant decrease in both cholinesterase activities. There were no significant between-group differences at any point in time. From these data it can be assumed that dexmedetomidine could alleviate POD via altering the cholinergic anti-inflammatory pathway (CAIP). We advocate for further investigations to show the direct connection between dexmedetomidine and cholinesterase activity.

Increased Enzymatic Activity of Acetylcholinesterase Indicates the Severity of the Sterile Inflammation and Predicts Patient Outcome following Traumatic Injury

Traumatic injury induces sterile inflammation, an immune response often associated with severe organ dysfunction. The cholinergic system acts as an anti-inflammatory in injured patients. Acetylcholinesterase (AChE), an enzyme responsible for the hydrolysis of acetylcholine, plays an essential role in controlling cholinergic activity. We hypothesized that a change in the AChE activity might indicate the severity of the traumatic injury. This study included 82 injured patients with an Injury Severity Score (ISS) of 4 or above and 40 individuals without injuries. Bedside-measured AChE was obtained on hospital arrival, followed by a second measurement 4-12 h later. C-reactive protein (CRP), white blood cell count (WBCC), and Sequential Organ Failure Assessment (SOFA) score were simultaneously collected. Injured patients showed an early and sustained increase in AChE activity. CRP remained unaffected at hospital admission and increased subsequently. Initially elevated WBCC recovered 4-12 h later. AChE activity directly correlated with the ISS and SOFA scores and predicted the length of ICU stay when measured at hospital admission. An early and sustained increase in AChE activity correlated with the injury severity and could predict the length of ICU stay in injured patients, rendering this assay a complementary diagnostic and prognostic tool at the hand of the attending clinician in the emergency unit.

Association between cholinesterase activity and critical illness brain dysfunction

BACKGROUND

Delirium is a frequent manifestation of acute brain dysfunction and is associated with cognitive impairment. The hypothesized mechanism of brain dysfunction during critical illness is centered on neuroinflammation, regulated in part by the cholinergic system. Point-of-care serum cholinesterase enzyme activity measurements serve as a real-time index of cholinergic activity. We hypothesized that cholinesterase activity during critical illness would be associated with delirium in the intensive care unit (ICU) and cognitive impairment after discharge.

METHODS

We enrolled adults with respiratory failure and/or shock and measured plasma acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity on days 1, 3, 5, and 7 after enrollment. AChE values were also normalized per gram of hemoglobin (AChE/Hgb). We assessed for coma and delirium twice daily using the Richmond Agitation Sedation Scale and the Confusion Assessment Method for the ICU to evaluate daily mental status (delirium, coma, normal) and days alive without delirium or coma. Cognitive impairment, disability, and health-related quality of life were assessed at up to 6 months post-discharge. We used multivariable regression to determine whether AChE, AChE/Hgb, and BChE activity were associated with outcomes after adjusting for relevant covariates.

RESULTS

We included 272 critically ill patients who were a median (IQR) age 56 (39-67) years and had a median Sequential Organ Failure Assessment score at enrollment of 8 (5-11). Higher daily AChE levels were associated with increased odds of being delirious versus normal mental status on the same day (Odds Ratio [95% Confidence Interval] 1.64 [1.11, 2.43]; P = 0.045). AChE/Hgb and BChE activity levels were not associated with delirious mental status. Lower enrollment BChE was associated with fewer days alive without delirium or coma (P = 0.048). AChE, AChE/Hgb, and BChE levels were not significantly associated with cognitive impairment, disability, or quality of life after discharge.

CONCLUSION

Cholinesterase activity during critical illness is associated with delirium but not with outcomes after discharge, findings that may reflect mechanisms of acute brain organ dysfunction.

TRIAL REGISTRATION

NCT03098472. Registered 31 March 2017.

Reduced serum cholinesterase is an independent risk factor for all-cause mortality in the pediatric intensive care unit

Objective

Our aim was to assess the relationship between serum cholinesterase levels at intensive care unit admission and all-cause mortality in the pediatric intensive care unit.

Methods

We used the pediatric intensive care unit database (a large pediatric intensive care database in China from 2010 to 2018) to conduct a retrospective analysis to evaluate the serum cholinesterase levels at intensive care unit admission of 11,751 critically ill children enrolled to the intensive care unit. We analyzed the association between serum cholinesterase and all-cause mortality. Adjusted smoothing spline plots, subgroup analysis and segmented multivariate logistic regression analysis were conducted to estimate the relative risk between proportional risk between serum cholinesterase and death.

Results

Of the 11,751 children, 703 (5.98%) died in hospital. After adjusting for confounders, there was a negative association between serum cholinesterase and the risk of death in pediatric intensive care unit. For every 1,000 U/L increase in serum cholinesterase, the risk of death was reduced by 16% (adjusted OR = 0.84, 95% CI: 0.79, 0.89). The results of sensitivity analysis showed that in different stratified analyses (age, intensive care unit category, albumin, alanine aminotransferase, creatinine, neutrophils), the effect of serum cholinesterase on all-cause mortality remained stable.

Conclusion

After adjusting for inflammation, nutrition, and liver function factors, cholinesterase reduction is still an independent risk factor for pediatric intensive care unit all-cause mortality.

Critically Ill COVID-19 Patients Show Reduced Point of Care-Measured Butyrylcholinesterase Activity—A Prospective, Monocentric Observational Study

A biomarker for risk stratification and disease severity assessment in SARS-CoV-2 infections has not yet been established. Point of care testing (POCT) of butyrylcholinesterase (BChE) enables early detection of systemic inflammatory responses and correlates with disease severity in sepsis and burns. In acute care or resource-limited settings, POCT facilitates rapid clinical decision making, a particularly beneficial aspect in the management of pandemic situations. In this prospective observational study, POCT-measured BChE activity was assessed in 52 critically ill COVID-19 patients within 24 h of ICU admission and on the third and seventh day after ICU admission. Forty (77%) of these patients required venovenous extracorporeal membrane oxygenation (vvECMO). In critically ill COVID-19 patients, BChE activity is significantly decreased compared with healthy subjects, but also compared with other inflammatory conditions such as sepsis, burns, or trauma. POCT BChE activity reflects the severity of organ dysfunction and allows prediction of 28-day mortality in critically ill COVID-19 patients. Implementing early POCT BChE measurement could facilitate risk stratification and support admission and transfer decisions in resource-limited settings.

Prognostic Value of Serum Cholinesterase Activity in Severe SARS-CoV-2-Infected Patients Requiring Intensive Care Unit Admission

We evaluated the prognostic value of serum cholinesterase (SChE) levels in SARS-CoV-2-infected patients requiring intensive care unit (ICU) admission. This is a retrospective study of severe, critically ill, adult COVID-19 patients, all of whom had a confirmed SARS-CoV-2 infection and were admitted into the ICU of a university hospital. We included all patients admitted to our ICU and whose SChE levels were explored on ICU admission and during ICU stay. One hundred and thirty-seven patients were included. There were 100 male and 37 female patients. The mean of SChE activity on ICU admission was 5,656 ± 1,818 UI/L (range: 1926-11,192 IU/L). The SChE activity on ICU admission was significantly lower in nonsurvivors (P < 0.001). A significant association between the SChE activity on ICU admission and the need for invasive mechanical ventilation was found. We also found a significant correlation between the SChE activity and other biomarkers of sepsis (C-reactive protein, procalcitonin, and leukocytes) on ICU admission and during the ICU stay. A significant correlation among SChE nadir value activity recorded during ICU stay, the occurrence of nosocomial infection, and the outcome of studied patients was found. Our study shows that the low SChE activity value is associated with a severe outcome. It might be used as a biomarker to aid in prognostic risk stratification in SARS-CoV-2-infected patients. Further studies for external validation of our findings are needed on this subject.

Prospective, observational, single-centre cohort study with an independent control group matched for age and sex aimed at investigating the significance of cholinergic activity in patients with schizophrenia: study protocol of the CLASH-study

INTRODUCTION

Alterations in the cholinergic metabolism may cause various clinical symptoms of schizophrenia. In addition to the 'monoamine hypothesis,' neuroinflammation is also discussed as a cause of schizophrenia. To date, there has been no evidence of alterations in the central cholinergic transmitter balance in patients with schizophrenia under clinical conditions. By contrast, studies in critically ill patients have established the measurement of acetylcholinesterase activity as a suitable surrogate parameter of central cholinergic transmitter balance/possible pathophysiological changes. Butyrylcholinesterase activity has been established as a parameter indicating possible (neuro)inflammatory processes. Both parameters can now be measured using a point-of-care approach. Therefore, the primary objective of this study is to investigate whether acetylcholinesterase and butyrylcholinesterase activity differs in patients with various forms of schizophrenia. Secondary objectives address the possible association between acetylcholinesterase and butyrylcholinesterase activity and (1) schizophrenic symptoms using the Positive and Negative Syndrome Scale, (2) the quantity of antipsychotics taken and (3) the duration of illness.

METHODS AND ANALYSIS

The study is designed as a prospective, observational cohort study with one independent control group. It is being carried out at the Department of Psychiatry and Psychotherapy III, Ulm University Hospital, Germany. Patient enrolment started in October 2020, and the anticipated end of the study is in January 2022. The enrolment period was set from October 2020 to December 2021 (extension required due to SARS-CoV-2 pandemic). The sample size is calculated at 50 patients in each group. Esterase activity is measured on hospital admission (acute symptomatology) and after referral to a postacute ward over a period of three consecutive days. The matched control group will be created after reaching 50 patients with schizophrenia. This will be followed by a comprehensive statistical analysis of the data set.

ETHICS AND DISSEMINATION

The study was registered prospectively in the German Clinical Trials Register (DRKS-ID: DRKS00023143,URL: https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00023143) after approval by the ethics committee of the University of Ulm, Germany Trial Code No. 280/20.

TRIAL REGISTRATION NUMBER

DRKS00023143; Pre-results.

Butyrylcholinesterase as a perioperative complication marker in patients after transcatheter aortic valve implantation: a prospective observational study

OBJECTIVES

Transcatheter aortic valve implantation (TAVI) is performed in elderly patients with severe aortic valve stenosis and increased operative risks. We tested the hypothesis that acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) have a predictive value for prevalent complications after TAVI and could serve as indicators of systemic inflammation in the early postoperative period.

DESIGN

Prospective observational study.

SETTING

This study is a secondary analysis of multicentre CESARO- study.

PARTICIPANTS

48 patients with TAVI were included and 43 obtained the complete assessment.

PRIMARY AND SECONDARY OUTCOME MEASURES

Patients' clinical parameters, demographic data, peripheral AChE and BChE activities and routine blood markers were assessed throughout the perioperative period using bedside point-of-care measurements for AChE and BChE. Postoperative complication screening was conducted up to the third postoperative day and included infections, delirium and heart-rhythm disturbances. After assessment, the patients were divided into complication and noncomplication group.

RESULTS

Of 43 patients, 24 developed postsurgical complications (55.8%). Preoperative assessment showed no significant differences regarding demographic data and laboratory markers, but preoperative BChE levels were significantly lower in patients who developed postoperative complications (complication group 2589.2±556.4 vs noncomplication group 3295.7±628.0, Cohen's r=0.514, p<0.001). In complication group, we observed an early, sustained reduction in BChE activity from preoperative to postoperative period. In complication group, BChE levels were significantly lower at each time point compared with noncomplication group. AChE activity showed no significant difference between both groups. Complication group also had longer stay in hospital overall.

CONCLUSION

BChE could be a useful perioperative biomarker to identify patients with a higher risk for postoperative complications after TAVI. By using point-of-care measurements, the levels of BChE are fast available and can lead to an early targeted therapy. Predicting the length of the hospital stay might play an important role in staff and resource management for these patients.

TRIAL REGISTRATION NUMBER

NCT01964274; Post-results.

Plasma cholinesterase activity is influenced by interactive effect between omethoate exposure and CYP2E1 polymorphisms

The aim of this study was to explore the association between metabolizing enzyme gene polymorphisms and the decrease in cholinesterase activity induced by omethoate exposure. A total of 180 workers exposed to omethoate over an extended period were recruited along with 115 healthy controls. Cholinesterase activity in whole blood, erythrocyte, and plasma was detected using acetylthiocholine and the dithio-bis-(nitrobenzoic acid) method. Six polymorphic loci of GSTT1(+/-), GSTM1(+/-), GSTP1 rs1695, CYP2E1 rs6413432, CYP2E1 rs3813867, and PON2 rs12026 were detected by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The gene-environment interactions were analyzed using the generalized linear model method. The cholinesterase activity of erythrocyte and plasma in the exposure group was significantly lower than that in the control group (P < 0.001) in general. The plasma cholinesterase activity in the TT + AT genotype in CYP2E1 rs6413432 was lower than that in the AA genotype in the exposure group (P = 0.016). Interaction between the AA genotype in CYP2E1 rs6413432 and omethoate exposure had a significant effect on plasma cholinesterase activity (P = 0.079). The decrease in plasma cholinesterase activity was associated with interaction between the AA genotypes in rs6413432 and omethoate exposure.

Different Pharmacokinetics of Tramadol, O-Demethyltramadol and N-Demethyltramadol in Postoperative Surgical Patients From Those Observed in Medical Patients

Background: Most studies examining tramadol metabolism have been carried out in non-surgical patients and with oral tramadol. The aim of this study was 1) to measure concentrations of tramadol, O-demethyltramadol (ODT), and N-demethyltramadol (NDT) in the surgical patients admitted to the intensive care unit (ICU) within the first 24 postoperative hours after intravenous application of tramadol, and 2) to examine the effect of systemic inflammation on tramadol metabolism and postoperative pain. Methods: A prospective observational study was carried out in the surgical ICU in the tertiary hospital. In the group of 47 subsequent patients undergoing major abdominal surgery, pre-operative blood samples were taken for CYP2D6 polymorphism analysis. Systemic inflammation was assessed based on laboratory and clinical indicators. All patients received 100 mg of tramadol intravenously every 6 h during the first postoperative day. Postoperative pain was assessed before and 30 min after tramadol injections. Tramadol, ODT, and NDT concentrations were determined by high-performance liquid chromatography. Results: CYP2D6 analysis revealed 2 poor (PM), 22 intermediate (IM), 22 extensive (EM), and 1 ultrafast metabolizer. After a dose of 100 mg of tramadol, t1/2 of 4.8 (3.2-7.6) h was observed. There were no differences in tramadol concentration among metabolic phenotypes. The area under the concentration-time curve at the first dose interval (AUC1-6) of tramadol was 1,200 (917.9-1944.4) μg ×h ×L-1. NDT concentrations in UM were below the limit of quantification until the second dose of tramadol was administrated, while PM had higher NDT concentrations compared to EM and IM. ODT concentrations were higher in EM, compared to IM and PM. ODT AUC1-6 was 229.6 (137.7-326.2) μg ×h ×L-1 and 95.5 (49.1-204.3) μg ×h ×L-1 in EM and IM, respectively (p = 0.004). Preoperative cholinesterase activity (ChE) of ≤4244 U L-1 was a cut-off value for a prediction of systemic inflammation in an early postoperative period. NDT AUC1-6 were significantly higher in patients with low ChE compared with normal ChE patients (p = 0.006). Pain measurements have confirmed that sufficient pain control was achieved in all patients after the second tramadol dose, except in the PM. Conclusions: CYP2D6 polymorphism is a major factor in O-demethylation, while systemic inflammation accompanied by low ChE has an important role in the N-demethylation of tramadol in postoperative patients. Concentrations of tramadol, ODT, and NDT are lower in surgical patients than previously reported in non-surgical patients. Clinical Trial Registration: ClinicalTrials.gov, NCT04004481.

Point-of-care measured serum cholinesterase activity predicts patient outcome following severe burns

Risk stratification is of utmost importance in burn therapy. However, suitable bedside biomarkers to evaluate the emerging inflammatory response following burn injuries are missing. Serum cholinesterase (butyrylcholinesterase, BChE) has been shown to be a clinically relevant biomarker in acute inflammatory diseases including burns. In this observational cohort study BChE activity was measured by using point-of-care testing (POCT), a novel method in acute burn care. POCT measurements were performed at emergency room admission (ERA) of 35 patients and repeated 12, 24 and 48 h later. All patients or their legal designees gave informed consent. Patients with burn injuries showed sustained BChE activity reduction following hospital admission. BChE activity correlated negatively with burn injury severity, organ failure severity and intensive care unit resource requirements. BChE activity measured at ERA and 12 h later identified survivors and predicted 28-day patient outcome with noninferior efficacy compared to the abbreviated burn severity index (ABSI) scoring. Finally, POCT-measured BChE activity might complement ABSI scoring and possibly improve early risk stratification in acute burn care therapy.

Cholinesterase alterations in delirium after cardiosurgery: a German monocentric prospective study

OBJECTIVES

Postoperative delirium (POD) is a common complication after elective cardiac surgery. Recent evidence indicates that a disruption in the normal activity of the cholinergic system may be associated with delirium.

DESIGN

Prospective observational study.

SETTING

Single-centre at a European academic hospital.

PRIMARY AND SECONDARY OUTCOME MEASURES

In our study the enzyme activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were determined preoperatively as well as on the first and second postoperative day. The confusion assessment method for the intensive care unit was used to screen patients for the presence of POD.

RESULTS

A total of 114 patients were included in the study. POD was associated with a decrease in BChE activity on postoperative day 1 (p=0.03). In addition, patients who developed POD, had significantly lower preoperative AChE activity than patients without POD (p<0.01). Multivariate analysis identified a preoperatively decreased AChE activity (OR 3.1; 95% CI 1.14 to 8.46), anticholinergic treatment (OR 5.09; 95% CI 1.51 to 17.23), elevated European System for Cardiac Operative Risk Evaluation (OR 3.68; 95% CI 1.04 to 12.99) and age (OR 3.02; 95% CI 1.06 to 8.62) to be independently associated with the development of POD.

CONCLUSIONS

We conclude that a reduction in the acetylcholine hydrolysing enzyme activity in patients undergoing cardiac surgery may correlate with the development of POD.

Bedside-measurement of serum cholinesterase activity predicts patient morbidity and length of the intensive care unit stay following major traumatic injury

Major traumatic injury (MTI), a life-threatening condition requiring prompt medical intervention, is associated with an extensive inflammatory response often resulting in multiple organ dysfunction. Early stratification of trauma severity and the corresponding inflammation may help optimize resources at the intensive care unit (ICU). The cholinergic system counters inflammation by quickly modulating the immune response. Serum cholinesterase (butyrylcholinesterase, BChE) is an enzyme that hydrolyses acetylcholine. We tested whether a change in the BChE activity correlates with the morbidity and the length of ICU stay. Blood samples from 10 healthy volunteers and 44 patients with MTI were gathered at hospital admission, followed by measurements 12, 24 and 48 hours later. Point-of-care approach was used to determine the BChE activity. Disease severity was assessed by clinical scoring performed within 24 hours following hospital admission. BChE activity, measured at hospital admission, showed a significant and sustained reduction and correlated with disease severity scores obtained 24 hours following admission. BChE activity, obtained at hospital admission, correlated with the length of ICU stay. Bedside measurement of BChE activity, as a complementary addition to established procedures, might prove useful in the primary assessment of the disease severity and might therefore optimize therapy in the ICU.

In Vivo Effects of Neostigmine and Physostigmine on Neutrophil Functions and Evaluation of Acetylcholinesterase and Butyrylcholinesterase as Inflammatory Markers during Experimental Sepsis in Rats

Introduction

Recent studies have shown that acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) may serve as important diagnostic and therapeutic targets in sepsis. Since polymorphonuclear neutrophils (PMNs) play a pivotal role in the early phase of sepsis, we evaluated the potential therapeutic effects of cholinesterase inhibitors on PMN functions during cecal ligation and puncture- (CLP-) induced sepsis and investigated the roles of AChE and BChE as inflammatory markers under standardized experimental conditions.

Methods

Sham surgery or CLP was performed in male Wistar rats (n = 60). Animals were randomized into four groups: physostigmine, 100 μg/kg; neostigmine, 75 μg/kg; 0.9% saline (control group); and sham group, each applied four times over 24 h. The levels of reactive oxygen species (ROS) production and CD11b/CD62l expression were quantified by flow cytometry at t = 0, 6, 15, 20, and 24 h. Blood gas analysis as well as AChE and BChE activity levels was measured by validated point-of-care measurements. Clinical scores and survival times were determined.

Results

CLP induced a significant increase in ROS production and CD11b upregulation by rat PMNs. Treatment with physostigmine or neostigmine significantly reduced ROS production and CD11b upregulation by PMNs 20 h after CLP induction. In physostigmine-treated animals, survival times were significantly improved compared to the control animals, but not in neostigmine-treated animals. While AChE activity significantly decreased in the control animals at t > 6 h, AChE activity did not change in the sham group. BChE activity decreased at t > 20 h in the control animals.

Conclusion

While AChE activity may serve as an acute inflammatory marker, BChE activity shows a delayed decrease. Administration of centrally acting physostigmine in CLP-induced sepsis in rats has protective effects on PMN functions and improves survival times, which may be of interest in clinical practice.

A Sustained Reduction in Serum Cholinesterase Enzyme Activity Predicts Patient Outcome following Sepsis

Early sepsis identification is of paramount importance for an effective therapy and the patient outcome; however, a suitable prognostic biomarker is lacking. Anti-inflammatory nonneuronal cholinergic signaling modulates the magnitude of an immune response. Serum cholinesterase (BChE), an enzyme that hydrolyzes acetylcholine, plays an important role during inflammatory response and serves as an accurate index of cholinergic activity. BChE activity was measured in septic patients using a point-of-care system, and levels of conventional inflammatory markers and the disease severity scores were obtained. We observed a strong, sustained reduction in BChE activity in patients who died within a 90-day observation period, as compared to survivors. Reduced BChE activity when measured at the ICU admission effectively differentiated between the 90-day survivor and the nonsurvivor patient groups. We estimated a critical BChE level of 1.661 kU/L (CI 0.5–0.8, 94% sensitivity, 48% specificity, AUC 0.7) to best predict patient outcome providing a benchmark criterion for early detection of potentially fatal sepsis measured at the admission. This finding suggests that the BChE activity, used in combination with the laboratory tests, clinical examination, and the disease severity scoring, could serve to identify high-risk patients at the ICU admission, the most critical time point in the sepsis treatment.