Admission Hyperglycemia Predicts Long-Term Mortality in Critically Ill Patients With Subarachnoid Hemorrhage: A Retrospective Analysis of the MIMIC-III Database

Multimodal imaging of the role of hyperglycemia following experimental subarachnoid hemorrhage

Hyperglycemia has been linked to worsening outcomes after subarachnoid hemorrhage (SAH). Nevertheless, the mechanisms involved in the pathogenesis of SAH have been scarcely evaluated so far. The role of hyperglycemia was assessed in an experimental model of SAH by T2 weighted, dynamic contrast-enhanced magnetic resonance imaging (T2W and DCE-MRI), [18F]BR-351 PET imaging and immunohistochemistry. Measures included the volume of bleeding, the extent of cerebral infarction and brain edema, blood brain barrier disruption (BBBd), neutrophil infiltration and matrix metalloprotease (MMP) activation. The neurofunctional outcome, neurodegeneration and myelinization were also investigated. The induction of hyperglycemia increased mortality, the size of the ischemic lesion, brain edema, neurodegeneration and worsened neurological outcome during the first 3 days after SAH in rats. In addition, these results show for the first time the exacerbating effect of hyperglycemia on in vivo MMP activation, Intercellular Adhesion Molecule 1 (ICAM-1) expression and neutrophil infiltration together with increased BBBd, bleeding volume and fibrinogen accumulation at days 1 and 3 after SAH. Notably, these data provide valuable insight into the detrimental effect of hyperglycemia on early BBB damage mediated by neutrophil infiltration and MMP activation that could explain the worse prognosis in SAH.

The association between blood pressure at admission and in-hospital mortality in patients with subarachnoid hemorrhage

PURPOSE

The objective of this study was to examine the association between mean arterial pressure (MAP) at admission and in-hospital mortality among patients diagnosed with subarachnoid hemorrhage (SAH).

METHODS

In this cohort study, 1420 SAH patients were categorized into four groups based on quartiles of MAP: <82 mmHg group, 82-93 mmHg group, 93-103 mmHg group, and >103 mmHg group. Furthermore, the X-tile program was used to divide all patients into four groups: < 81.7 mmHg group, 81.7-92.3 mmHg group, 92.3-103.7 mmHg group, and > 103.7 mmHg group. The association between MAP and in-hospital mortality of SAH patients was evaluated using univariate and multivariable Cox proportional hazards models. A restricted cubic spline (RCS) was plotted to explore the association between MAP at admission and in-hospital mortality in patients with SAH.

RESULTS

The median follow-up duration was 7.87 days, during which, 1219 (85.85%) patients survived. After adjusting for confounding factors, MAP <82 mmHg (hazard ratio (HR)=1.67, 95% confidence interval (CI): 1.08-2.57) or MAP >103 mmHg (HR=2.13, 95% CI: 1.38-3.29) was associated with increased risk of in-hospital mortality of SAH patients. Subgroup analysis depicted that MAP <82 mmHg or MAP >103 mmHg was associated with increased risk of in-hospital mortality in male patients or those aged ≥ 65 years. MAP >103 mmHg was linked with elevated risk of in-hospital mortality in patients aged <65 years; individuals with normal and underweight, overweight, and obesity; or people with hypertension.

CONCLUSION

The findings may offer a preliminary estimate of the optimum range for SAH patients for future randomized trials.

Synergistic effect of elevated glucose levels with SARS-CoV-2 spike protein induced NOX-dependent ROS production in endothelial cells

BACKGROUND

Diabetic patients infected with coronavirus disease 2019 (COVID-19) often have a higher probability of organ failure and mortality. The potential cellular mechanisms through which blood glucose exacerbates tissue damage due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is still unclear.

METHODS AND RESULTS

We cultured endothelial cells within differing glucose mediums with an increasing concentration gradient of SARS-CoV-2 Spike protein (S protein). S protein can cause the reduction of ACE2 and TMPRSS2, and activation of NOX2 and NOX4. A high glucose medium was shown to aggravate the decrease of ACE2 and activation of NOX2 and NOX4 in cultured cells, but had no effect on TMPRSS2. S protein mediated activation of the ACE2-NOX axis induced oxidative stress and apoptosis within endothelial cells, leading to cellular dysfunction via the reduction of NO and tight junction proteins which may collectively be exacerbated by elevated glucose. In addition, the glucose variability model demonstrated activation of the ACE2-NOX axis in a similar manner observed in the high glucose model in vitro.

CONCLUSIONS

Our present study provides evidence for a mechanism through which hyperglycemia aggravates endothelial cell injury resulting from S protein mediated activation of the ACE2-NOX axis. Our research thus highlights the importance of strict monitoring and control of blood glucose levels within the context of COVID-19 treatment to potentially improve clinical outcomes.

The Role of MicroRNAs in Predicting the Neurological Outcome of Patients with Subarachnoid Hemorrhage: A Meta-analysis

Subarachnoid hemorrhage (SAH) is a hemorrhagic cerebrovascular disease with an extremely poor prognosis. The molecular mechanism and biomarkers involved in neurological outcome after SAH still need to be explored. This study assessed the microRNA expression characteristics of SAH patients with different neurological outcomes by meta-analysis. Public databases were searched from database inception until December 2022. The study reported that microRNA expression data in SAH patients with different neurological outcomes were included in the analysis. The differential expression of miRNAs was evaluated by meta-analysis. Overrepresentation analysis was performed for the targeted genes of significant miRNAs. The XGBoost algorithm was used to assess the predictive ability for neurological outcomes with clinical characteristics and significantly expressed miRNAs. Seven studies were finally included in the meta-analysis. The results showed that the levels of miR-152-3p (SMD: - 0.230; 95% CI - 0.389, - 0.070; padj = 0.041), miR-221-3p (SMD: - 0.286; 95% CI - 0.446, - 0.127; padj = 0.007), and miR-34a-5p (SMD: - 0.227; 95% CI - 0.386, - 0.067; padj = 0.041) were significantly lower in SAH patients with good neurological outcomes than in those with poor neurological outcomes. The PI3K-AKT signaling pathway may have an important role in neurological recovery after SAH. Based on the XGBoost algorithm, the neurological outcome could be accurately predicted with clinical characteristics plus the three miRNAs. The expression levels of miR-152-3p, miR-221-3p, and miR-34a-5p were significantly lower in patients with good neurological outcomes than in those with poor outcomes. These miRNAs can serve as potential predictive biomarkers for neurological outcomes. The molecular mechanism and biomarkers involved in neurological outcome after SAH still need to be explored. Our study analyzed microRNA expression characteristics of SAH patients with different neurological outcomes by meta-analysis. After analyze studies reporting the microRNA expression data in SAH patients with different neurological outcomes, results show that the levels of miR-152-3p, miR-221-3p, and miR-34a-5p were significantly lower in SAH patients with good neurological outcomes than in those with poor neurological outcomes. The PI3K-AKT signaling pathway may have an important role in neurological recovery after SAH. Based on the XGBoost algorithm, the neurological outcome could be accurately predicted with clinical characteristics plus the three miRNAs.

Clinical relevance of glucose metrics during the early brain injury period after aneurysmal subarachnoid hemorrhage: An opportunity for continuous glucose monitoring

Hyperglycaemia, hypoglycaemia and higher glucose variability during the Early Brain Injury (EBI) period of aneurysmal subarachnoid hemorrhage (aSAH) have been associated with poor clinical outcome. However, it is unclear whether these associations are due to direct glucose-driven injury or if hyperglycaemia simply acts as a marker of initial severity. Actually, strict glucose control with intensive insulin therapy has not been demonstrated as an effective strategy for improving clinical outcomes after aSAH. Currently published studies describing an association between hyperglycaemia and prognosis in aSAH patients have been based on isolated glucose measurements and did not incorporate comprehensive dynamic evaluations, such as those derived from subcutaneous continuous glucose monitoring devices (CMG). Arguably, a more accurate knowledge on glycaemic patterns during the acute phase of aSAH could increase our understanding of the relevance of glycaemia as a prognostic factor in this disease as well as to underpin its contribution to secondary focal and diffuse brain injury. Herein, we have summarized the available evidence on the diagnostic and prognostic relevance of glucose metrics during the acute phase of cerebrovascular diseases, focusing in the EBI period after aSAH. Overall, obtaining a more precise scope of acute longitudinal glucose profiles could eventually be useful for improving glucose management protocols in the setting of acute aSAH and to advance toward a more personalized management of aSAH patients during the EBI phase.

Relationship between the mean of 24-h venous blood glucose and in-hospital mortality among patients with subarachnoid hemorrhage: A matched cohort study

Objective

The aim of this study was to explore the correlation between the mean of 24-h venous blood glucose (BG) and in-hospital mortality and all-cause mortality (ACM) in patients with subarachnoid hemorrhage (SAH).

Methods

Detailed clinical information was acquired from the Medical Information Mart for Intensive IV (MIMIC-IV) database. The best cutoff value of mean BG was calculated using the X-tile program. Univariate and multivariate logistic regressive analyses were utilized to analyze the prognosis significance of mean BG, and survival curves were drawn using the Kaplan-Meier (K-M) approach. To improve the reliability of results and balance the impact of underlying confounders, the 1:1 propensity score matching (PSM) approach was utilized.

Results

An overall of 1,230 subjects were selected herein. The optimal cutoff value of the mean BG for in-hospital mortality was 152.25. In addition, 367 pairs of score-matched subjects were acquired after PSM analysis, and nearly all variables' differences were balanced. K-M analysis showed that patients with mean BG ≥ 152.25 mg/dl had significantly higher in-hospital, 3-month, and 6-month mortalities compared with patients with mean BG < 152.25 mg/dl (p < 0.001). The multivariable logistic regressive analyses revealed that patients with mean BG ≥ 152.25 mg/dl had significantly increased in-hospital mortality compared with patients with mean BG < 152.25 mg/dl after the adjustment for possible confounders (OR = 1.994, 95% CI: 1.321–3.012, p = 0.001). Similar outcomes were discovered in the PSM cohort.

Conclusion

Our data suggested that mean BG was related to ACM of patients with SAH. More studies are needed to further analyze the role of the mean of 24-h venous BG in patients with SAH.