Predictive value of different bilirubin subtypes for clinical outcomes in patients with acute ischemic stroke receiving thrombolysis therapy

The protective role of endothelial GLUT1 in ischemic stroke

OBJECTIVE

To provide thorough insight on the protective role of endothelial glucose transporter 1 (GLUT1) in ischemic stroke.

METHODS

We comprehensively review the role of endothelial GLUT1 in ischemic stroke by narrating the findings concerning biological characteristics of GLUT1 in brain in depth, summarizing the changes of endothelial GLUT1 expression and activity during ischemic stroke, discussing how GLUT1 achieves its neuroprotective effect via maintaining endothelial function, and identifying some outstanding blind spots in current studies.

RESULTS

Endothelial GLUT1 maintains persistent high glucose and energy requirements of the brain by transporting glucose through the blood-brain barrier, which preserves endothelial function and is beneficial to stroke prognosis.

CONCLUSION

This review underscores the potential involvement of GLUT1 trafficking, activity modulation, and degradation, and we look forward to more clinical and animal studies to illuminate these mechanisms.

Higher baseline serum bilirubin levels are associated with increased risk of early neurological deterioration in women with acute ischemic stroke

Background and objectives

Early neurological deterioration (END) occurs in up to one-third of patients with acute ischemic stroke (AIS) and associated with poor outcome. The role of serum bilirubin in END remains controversial. This study aims to investigate the association of total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) with END.

Methods

This study was a cross-sectional retrospective study with 344 AIS patients enrolled. We retrospectively reviewed consecutive AIS patients with END through a medical record retrieval system and enrolled patients as control randomly from the AIS patients without END at the same period. The bilirubin levels were compared between the END group and No END group. The correlations of bilirubin with END were assessed according to the bilirubin tertiles on the cohort of different genders.

Results

In women, as the bilirubin level increased, the occurrence of END showed an increasing trend. The linear association was significant based on the tertiles of all bilirubin types (TBIL p = 0.003; DBIL p = 0.025; IBIL p = 0.025), while in men no similar trend was observed. After adjustment for confounders, higher TBIL (p for trend 0.009) and DBIL (p for trend 0.033) levels were associated with increased risk of END in women. The adjusted OR for T3 relative to T1 was 5.240 (95% CI 1.496-18.347) in TBIL and 3.549 (95% CI 1.089-11.566) in DBIL. Multivariate logistic regression showed that DBIL was independently associated with END in women (OR 1.717, 95% CI 1.106-2.666). The study also found that DBIL was superior to TBIL and IBIL in prediction of END occurrence in women, with greater predictive value.

Discussion

There were gender differences in the relationship between bilirubin and END, and DBIL level was positively associated with END occurrence in women, not in men. DBIL had greater incremental predictive value for END than TBIL and IBIL.

Supra-Blan2 t score as a multisystem-based risk score to predict poor 3-month outcome in acute ischemic stroke patients with intravenous thrombolysis

AIM

To develop and validate a novel weighted score integrating multisystem laboratory and clinical variables to predict poor 3-month outcome (mRS score of 3-6) in acute ischemic stroke (AIS) patients with intravenous thrombolysis (IVT) therapy.

METHODS

We retrospectively analyzed data from Trial of Revascularization Treatment for Acute Ischemic Stroke study. The Supra-Blan2 t score was derived using the data on age, the National Institutes of Health Stroke Scale score, history of atrial fibrillation, blood sugar level, neutrophil count, direct bilirubin level, platelet-lymphocyte ratio, and TnI level in the derivation cohort of 433 patients, and validated in a cohort of 525 patients. Furthermore, we compared the performance of the Supra-Blan2 t score with DRAGON, TURN, and SPAN-100 scores.

RESULTS

The discrimination capacity in the derivation and validation cohorts was good for poor 3-month outcome (the area under the curve was 0.821 and 0.843, respectively). The cumulative incidence of poor 3-month outcome significantly increased across risk categories in the derivation (low-risk, 9.2%; medium-risk, 17.4%; and high-risk, 58.8%) and validation cohorts (12.7%, 36.5%, and 73.6%, respectively). The performance of the Supra-Blan2 t score was similar to or superior to DRAGON, TURN, and SPAN-100 scores.

CONCLUSION

The Supra-Blan2 t score, based on easily available multisystem laboratory and clinical variables, reliably predicted poor 3-month functional outcome in AIS patients treated with IVT therapy featuring good calibration and discrimination.

High indirect bilirubin levels as an independent predictor of postoperative myasthenic crisis: a single-center, retrospective study

Background

Thymectomy is an efficient and standard treatment strategy for patients with myasthenia gravis (MG), postoperative myasthenic crisis (POMC) is the major complication related to thymectomy and has a strongly life-threatening effect. As a biomarker, whether the bilirubin level is a risk factor for MG progression remains unclear. This study aimed to investigate the association between the preoperative bilirubin level and postoperative myasthenic crisis (POMC).

Methods

We analyzed 375 patients with MG who underwent thymectomy at Tangdu Hospital between January 2012 and September 2021. The primary outcome measurement was POMC. The association between POMC and bilirubin level was analyzed by restricted cubic spline (RCS). Indirect bilirubin (IBIL) was divided into two subgroups based on the normal upper limit of IBIL, 14 μmol/L.

Results

Compared with non-POMC group, IBIL levels were significantly higher in patients with POMC. Elevated IBIL levels were closely associated with an increased risk of POMC (p for trend = 0.002). There was a dose-response curve relationship between IBIL levels and POMC incidence (p for non-linearity = 0.93). However, DBIL levels showed a U-shaped association with POMC incidence. High IBIL level (≥14 μmol/L) was an independent predictive factor for POMC [odds ratio = 3.47, 95% confidence interval (CI): 1.56-7.8, p = 0.002]. The addition of high IBIL levels improved the prediction model performance (net reclassification index = 0.186, 95% CI: 0.039-0.334; integrated discrimination improvement = 0.0345, 95% CI: 0.005-0.065).

Conclusion

High preoperative IBIL levels, especially those exceeding the normal upper limit, could independently predict the incidence of POMC.

Direct bilirubin: A predictor of hematoma expansion after intracerebral hemorrhage

BACKGROUND

Previous evidence demonstrated that several biomarkers involved in the pathological process of coagulation/hemostasis dysfunction, impairment of brain vascular integrity and inflammation are associated with hematoma expansion (HE) after intracerebral hemorrhage (ICH). We aimed to explore whether there were unreported laboratory biomarkers associated with HE that were readily and commonly available in clinical practice.

METHODS

We retrospectively analyzed consecutive acute ICH patients from 2012 to 2020 with admission laboratory tests and baseline and follow-up computed tomography (CT) scans. Univariate and multivariate regression analyses were used to evaluate associations between conventional laboratory indicators and HE. The results were verified in a prospective validation cohort. The relationship of candidate biomarker and 3-month outcomes was also investigated and mediation analysis was undertaken to determine causal associations among candidate biomarker, HE and outcome.

RESULTS

Of 734 ICH patients, 163 (22.2%) presented HE. Among the included laboratory indicators, higher direct bilirubin (DBil) was associated with HE (adjusted odds ratio [OR] of per 1.0 μmol/L change 1.082; 95% confidence interval [CI] 1.011-1.158). DBil >5.65 μmol/L was a predictor of HE in validation cohort. Higher DBil was also associated with poor 3-month outcomes. The mediation analysis indicated that the association of higher DBil and poor outcomes was partially mediated by HE.

CONCLUSIONS

DBil is a predictor of HE and poor 3-month outcomes after ICH. DBil's metabolic process and involvement in the pathological mechanism of HE are likely to contribute to the association between DBil and HE. Interventions targeting DBil to improve post-ICH prognosis may be meaningful and worthy of further exploration.

Hepatic responses following acute ischemic stroke: A clinical research update

Acute ischemic stroke (AIS) not only affects the brain but also has significant implications for peripheral organs through neuroendocrine regulation. This reciprocal relationship influences overall brain function and stroke prognosis. Recent research has highlighted the importance of poststroke liver changes in determining patient outcomes. In our previous study, we investigated the relationship between stroke and liver function. Our findings revealed that the prognostic impact of stress-induced hyperglycemia in patients undergoing acute endovascular treatment for acute large vessel occlusion is closely related to their preexisting diabetes status. We found that the liver contributes to stress hyperglycemia after AIS by increasing hepatic gluconeogenesis and decreasing hepatic insulin sensitivity. These changes are detrimental to the brain, particularly in patients without diabetes. Furthermore, we examined the role of bilirubin, a byproduct of hepatic hemoglobin metabolism, in stroke pathophysiology. Our results demonstrated that blood bilirubin levels can serve as predictors of stroke severity and may hold therapeutic potential for reducing oxidative stress-induced stroke injury in patients with mild stroke. These results underscore the potential role of the liver in the oxidative stress response following AIS, paving the way for further investigation into liver-targeted therapeutic strategies to improve stroke prognosis and patient outcomes.

Association between bilirubin levels with incidence and prognosis of stroke: A meta-analysis

Objective

Bilirubin has anti-inflammatory, antioxidant, and neuroprotective properties, but the association between bilirubin and stroke remains contentious. A meta-analysis of extensive observational studies on the relationship was conducted.

Methods

Studies published before August 2022 were searched in PubMed, EMBASE, and Cochrane Library. Cohort, cross-sectional and case-control studies that examined the association between circulating bilirubin and stroke were included. The primary outcome included the incidence of stroke and bilirubin quantitative expression level between stroke and control, and the secondary outcome was stroke severity. All pooled outcome measures were determined using random-effects models. The meta-analysis, subgroup analysis, and sensitivity analysis were performed using Stata 17.

Results

A total of 17 studies were included. Patients with stroke had a lower total bilirubin level (mean difference = -1.33 μmol/L, 95% CI: -2.12 to -0.53, P < 0.001). Compared with the lowest bilirubin level, total odds ratio (OR) of the highest bilirubin for the occurrence of stroke was 0.71 (95% CI: 0.61-0.82) and ischemic stroke was 0.72 (95% CI: 0.57-0.91), especially in cohort studies with accepted heterogeneity (I 2 = 0). Serum total and direct bilirubin levels were significantly and positively associated with stroke severity. A stratified analysis based on gender showed that the total bilirubin level in males correlated with ischemic stroke or stroke, which was not noted in females.

Conclusion

While our findings suggest associations between bilirubin levels and stroke risk, existing evidence is insufficient to establish a definitive association. Better-designed prospective cohort studies should further clarify pertinent questions (PROSPERO registration number: CRD42022374893).

Higher serum bilirubin levels are associated with hemorrhagic transformation after intravenous thrombolysis in acute ischemic Stroke

Background

Bilirubin has both antioxidative and prooxidative properties. The study aimed to explore the relationship between serum bilirubin and hemorrhagic transformation (HT) after intravenous thrombolysis in patients with acute ischemic stroke.

Methods

The patients receiving intravenous thrombolysis with alteplase were retrospectively analyzed. HT was defined as new intracerebral hemorrhage in follow-up computed tomography images within 24-36 h after thrombolysis. Symptomatic intracranial hemorrhage (sICH) was defined as HT accompanied by worsening neurological function. Multivariate logistic regression and spline regression models were performed to investigate the relationship between serum bilirubin levels and the risk of HT and sICH.

Results

Among 557 included patients, 71 (12.7%) were diagnosed with HT and 28 (5.0%) developed sICH. Patients with HT had significant higher baseline serum total bilirubin, direct bilirubin, and indirect bilirubin levels than those without HT. Multivariable logistic regression analysis indicated that patients with higher serum bilirubin levels, including total bilirubin (OR 1.05, 95% CI 1.01-1.08, p = 0.006), direct bilirubin (OR 1.18, 95% CI 1.05-1.31, p = 0.004), and indirect bilirubin (OR 1.06, 95% CI 1.02-1.10, p = 0.005) had increased risk of HT. Furthermore, multiple-adjusted spline regression models excluded nonlinear association between serum bilirubin levels and HT (p > 0.05 for nonlinearity). Similar results were present between serum bilirubin and sICH.

Conclusion

The data showed the positively linearly relationship between serum bilirubin levels and the risk of HT and sICH in patients with acute ischemic stroke undergoing intravenous thrombolysis.

Low serum magnesium is associated with poor functional outcome in acute ischemic stroke or transient ischemic attack patients

AIM

The association between magnesium and outcomes after stroke is uncertain. We aimed to investigate the association of serum magnesium with all-cause mortality and poor functional outcome.

METHODS

We included patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA) from the China National Stroke Registry III. We used Cox proportional hazards model for all-cause mortality and logistic regression model for poor functional outcome (modified Rankin Scale [mRS] 2-6/3-6) to examine the relationships.

RESULTS

Among the 6483 patients, the median (interquartile range) magnesium was 0.87 (0.80-0.93) mmol/L. Patients in the first quartile had a higher risk of mRS score 3-6/2-6 at 3 months (adjusted odds ratio [OR]: 1.30; 95% confidence interval [CI]: 1.02, 1.64; adjusted OR: 1.29; 95% CI: 1.04-1.59) compared with those in the fourth quartile. Similar results were found for mRS score 26 at 1 year. The age- and sex-adjusted hazard ratio (HR) with 95% CI in first quartile magnesium was 1.40 (1.02-1.93) for all-cause mortality within 1 year, but became insignificant (HR: 1.03; 95% CI: 0.71-1.50) after adjusting for potential variables.

CONCLUSIONS

Low serum magnesium was associated with a high risk of poor functional outcome in patients with AIS or TIA.

Specific subsystems of the inferior parietal lobule are associated with hand dysfunction following stroke: A cross-sectional resting-state fMRI study

AIM

The inferior parietal lobule (IPL) plays important roles in reaching and grasping during hand movements, but how reorganizations of IPL subsystems underlie the paretic hand remains unclear. We aimed to explore whether specific IPL subsystems were disrupted and associated with hand performance after chronic stroke.

METHODS

In this cross-sectional study, we recruited 65 patients who had chronic subcortical strokes and 40 healthy controls from China. Each participant underwent the Fugl-Meyer Assessment of Hand and Wrist and resting-state fMRI at baseline. We mainly explored the group differences in resting-state effective connectivity (EC) patterns for six IPL subregions in each hemisphere, and we correlated these EC patterns with paretic hand performance across the whole stroke group and stroke subgroups. Moreover, we used receiver operating characteristic curve analysis to distinguish the stroke subgroups with partially (PPH) and completely (CPH) paretic hands.

RESULTS

Stroke patients exhibited abnormal EC patterns with ipsilesional PFt and bilateral PGa, and five sensorimotor-parietal/two parietal-temporal subsystems were positively or negatively correlated with hand performance. Compared with CPH patients, PPH patients exhibited abnormal EC patterns with the contralesional PFop. The PPH patients had one motor-parietal subsystem, while the CPH patients had one sensorimotor-parietal and three parietal-occipital subsystems that were associated with hand performance. Notably, the EC strength from the contralesional PFop to the ipsilesional superior frontal gyrus could distinguish patients with PPH from patients with CPH.

CONCLUSIONS

The IPL subsystems manifest specific functional reorganization and are associated with hand dysfunction following chronic stroke.