Prediabetes is associated with post-stroke cognitive impairment in ischaemic stroke patients

High triglyceride-glucose index at admission is a predictor of post-stroke cognitive impairment in patients with acute ischemic stroke

BACKGROUND

Post-stroke cognitive impairment (PSCI) is a very common complication of ischemic stroke (IS). Triglyceride-glucose (TyG) index was an effective alternative marker of insulin resistance (IR). This prospective study was designed to explore the correlation between TyG index and PSCI.

METHODS

Between January 1 2021 to June 30 2022, consecutive patients with first onset IS were enrolled prospectively. Baseline information was collected at admission and fasting blood was drawn the next morning. Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive function at three months after stroke. Multiple regression analysis was used to explore the correlation between PSCI and TyG. Receiver operating characteristic (ROC) was performed to evaluate the predictive ability.

RESULTS

Ultimately, 313 patients were enrolled in this study. The TyG index was higher in patients with PSCI than those without PSCI (8.99 (8.55, 9.54) vs. 8.61(8.25, 8.87), P<0.001). The spearman correlation analysis indicated that TyG index was negatively correlated with MoCA score (r=-0.272, P<0.001). The multivariate logistic regression analysis demonstrated that TyG index was correlated with PSCI independently (P<0.001) regardless of whether the patients had diabetes or not. The area under curve (AUC) of the ROC was 0.684 (95%CI=0.635-0.768, P<0.001). The optimal cutoff value of TyG index for predicting PSCI was 8.81, with a sensitivity of 61.7% and a specificity of 73.6%.

CONCLUSION

A higher TyG index level at admission was independently correlated with increased risk of PSCI three months later and could be used as a predictor.

Association between diabetes mellitus and post-stroke cognitive impairment

Stroke survivors suffer from various physical, emotional, and cognitive impairments. These changes are dynamic and depend on multiple factors, including underlying diseases, baseline brain function and pathology, the site of the stroke and the post-stroke inflammation, neurogenesis as well as the subsequent remodeling of the neuro-network. First we review the structural and pathological changes of the brain in stroke survivors with diabetes mellitus, which may lead to post-stroke cognitive dysfunction. Second, we provide evidence of hyperglycemia, diabetes mellitus, hypoglycemia, and their relationship with post-stroke cognitive impairment (PSCI) and post-stroke dementia (PSD). In addition to conventional biomarkers, such as HbA1c, we also provide other novel tools to predict PSCI/PSD, such as glycemic variability, receptor for advanced glycation end products, and gut microbiota. Finally, we attempt to provide some modifying methods for glycemic control, focusing on the prevention of PSCI/PSD.

Microglia and bradykinin cross talk in poststroke cognitive impairment in diabetes

Stroke is one of the leading causes of mortality and the leading cause of long-term disability worldwide. Although cognitive impairment is a common consequence of stroke, the underlying pathophysiological processes that lead to it are still poorly understood. Recently, more studies have shown evidence of the involvement of diabetes in producing a chronic neuroinflammatory state, which ultimately alters the recovery of function and cognition after stroke. To better understand the impact of diabetes on poststroke recovery, here we highlight the recent insights on the role of diabetes in neuroinflammation, especially regarding its effect on microglial function, and the emerging data on the involvement of kinins in both diabetes and neuroinflammation.

Reduced thiamine is a predictor for cognitive impairment of cerebral infarction

OBJECTIVE

Reduced thiamine (vitamin B₁ ) had been reported to be associated with cognitive impairment caused by Alzheimer disease. Our study is to explore the association between thiamine and cognitive impairment after acute ischemic stroke.

MATERIALS AND METHODS

One hundred and eighty two patients with acute cerebral infarction were recruited within the first 24 hr after admission. Thiamine and other vitamin Bs of peripheral blood samples were measured. Patients were divided into with poststroke cognitive impairment (PSCI) and non-PSCI according to the score of MMSE and the degree of education.

RESULTS

Reduced thiamine (<1.0 ng/ml) was independently associated with PSCI (OR: 2.033, 95% CI: 1.017-4.067, p = .045) after adjusting for potential confounding factors. Advanced age, lower education, diabetes mellitus, left hemisphere infarction, and higher National Institute of Health Stroke Scale (NIHSS) were also independent risk factors for PSCI.

CONCLUSIONS

Reduced thiamine is one of the predictors for early cognitive impairment in patients with acute cerebral infarction.

The association between serum uric acid level and the risk of cognitive impairment after ischemic stroke

Post-stroke cognitive impairment (PSCI) is a severe complication of stroke. Predicting PSCI is difficult because some risk factors for stroke, such as blood glucose level and blood pressure, are affected by many other elements. Although recent studies have shown that high serum uric acid (UA) levels are associated with cognitive dysfunction and may be a risk factor for PSCI, its impact remains unclear. Accordingly, the present study aimed to explore the association between serum UA level and PSCI. In total, 274 patients who experienced acute cerebral infarction, confirmed between January 2016 and December 2018, were enrolled. Baseline data and biological indicators were recorded. According to the Montreal Cognitive Assessment (MoCA) scores, patients were divided into two groups: PSCI and non-PSCI. Logistic regression analysis was used to determine possible risk factors for PSCI. Results demonstrated that serum UA levels were significantly higher in the PSCI group than in the non-PSCI group. Multivariable logistic analysis revealed that age, years of education, and UA level were independent risk factors for PSCI. PSCI patients were subdivided according to serum UA level: high and low. Hypertension history and homocysteine (Hcy) levels differed significantly between the high and low UA level groups. Further analysis revealed that a history of hypertension and Hcy demonstrated a certain correlation (r = 0.163, 0.162; P < 0.05), suggesting that serum UA level was an independent risk factor for PSCI. These findings indicate that serum UA level was correlated with PSCI in post-stroke patients and is anticipated to be used in clinical practice to reduce the incidence of PSCI.

Association of Prediabetes and Type 2 Diabetes With Cognitive Function After Stroke: A STROKOG Collaboration Study

Background and Purpose- Type 2 diabetes mellitus (T2D) is associated with cognitive impairment and an increased risk of dementia, but the association between prediabetes and cognitive impairment is less clear, particularly in a setting of major cerebrovascular events. This article examines the impact of impaired fasting glucose and T2D on cognitive performance in a stroke population. Methods- Seven international observational studies from the STROKOG (Stroke and Cognition) consortium (n=1601; mean age, 66.0 years; 70% Asian, 26% white, and 2.6% African American) were included. Fasting glucose level (FGL) during hospitalization was used to define 3 groups, T2D (FGL ≥7.0 mmol/L), impaired fasting glucose (FGL 6.1-6.9 mmol/L), and normal (FGL <6.1 mmol/L), and a history of diabetes mellitus and the use of a diabetes mellitus medication were also used to support a diagnosis of T2D. Domain and global cognition Z scores were derived from standardized neuropsychological test scores. The cross-sectional association between glucose status and cognitive performance at 3 to 6 months poststroke was examined using linear mixed models, adjusting for age, sex, education, stroke type, ethnicity, and vascular risk factors. Results- Patients with T2D had significantly poorer performance in global cognition (SD, -0.59 [95% CI, -0.82 to -0.36]; P<0.001) and in all domains compared with patients with normal FGL. There was no significant difference between impaired fasting glucose patients and those with normal FGL in global cognition (SD, -0.10 [95% CI, -0.45 to 0.24]; P=0.55) or in any cognitive domain. Conclusions- Diabetes mellitus, but not prediabetes, is associated with poorer cognitive performance in patients 3 to 6 months after stroke.

Recombinant Human Growth Hormone Ameliorates Cognitive Impairment in Stroke Patients

OBJECTIVE

We aimed to determine the effects of recombinant human growth hormone (rhGH) replacement on cognitive function in subjects with poststroke cognitive impairment using resting-state functional magnetic resonance imaging.

METHODS

We included 60 patients with a first-ever stroke for 3 months and a diagnosis of cognitive impairment who were randomized 1:1 to receive either rhGH subcutaneously or placebo injection for 6 months. All subjects were required to receive the same rehabilitative therapy program. Both groups were subjected to pretreatment and posttreatment neuropsychological assessment using the Montreal Cognitive Assessment, serum neurotrophic factors, biomarkers of glucose and lipid metabolism, and functional magnetic resonance imaging during 6 months of the study period. The pattern of brain activity was determined by examining the functional connectivity and amplitude of low-frequency fluctuations (ALFF) of blood oxygen level dependent signal.

RESULTS

Forty-three (82.7%) completed the study. Treatment with rhGH reduced levels of triglycerides and low-density lipoprotein cholesterol but did not significantly altered plasma concentrations of glucose and glycated hemoglobin. We found a significant increase in serum insulin-like growth factor 1 levels (32.6%; P < 0.001) in the rhGH-treated group compared with that in the controls. After 6 months of rhGH treatment, mean Montreal Cognitive Assessment score improved from 16.31 (5.32) to 21.19 (6.54) (P < 0.001). The rhGH group showed significant increased area of activation with increased ALFF values in the regions of the frontal lobe, putamen, temporal lobe, and thalamus (P < 0.05), relative to the baseline conditions. The correlation analysis revealed that the ALFF and functional connectivity of default mode network was positively correlated with the ΔMoCA score and ΔIGF-1 levels; that is, the more the scale score increased, the higher the functional connection strength. No undesirable adverse effects were observed.

CONCLUSIONS

The rhGH replacement has a significant impact on global and domain cognitive functions in poststroke cognitive impairment.

The importance of stroke as a risk factor of cognitive decline in community dwelling older and oldest peoples: the SONIC study

Background

Cognitive impairment is a major health concern among older and oldest people. Moreover, stroke is a relevant contributor for cognitive decline and development of dementia. The study of cognitive decline focused on stroke as the important risk factor by recruiting older and oldest is still lagging behind. Therefore, the aim of this study was to investigate the importance of stroke as a risk factor of cognitive decline during 3 years in community dwelling older and oldest people.

Methods

This study was longitudinal study with a 3-year follow-up in Japan. The participants were 1333 community dwelling older and oldest people (70 years old = 675, 80 years old = 589, and 90 years old = 69). Data collected included basic data (age, sex, and history of stroke), vascular risk factors (hypertension, diabetes mellitus, dyslipidemia, atrial fibrillation, and current smoking), and social factors (educational level, frequency of going outdoors, long-term care (LTC) service used, and residential area). The Japanese version of the Montreal Cognitive Assessment (MoCA-J) was decline of ≥2 points was defined as cognitive decline. Multiple logistic regression analysis was used to investigate the association between stroke and other risk factors with cognitive decline during a 3-year follow-up.

Results

The fit of the hypothesized model by multiple logistic regression showed that a history of stroke, advanced age, and greater MoCA-J score at the baseline were important risk factors, while the presence of dyslipidemia and a higher educational level were protective factors that were significantly correlated with cognitive decline during the 3-year follow-up.

Conclusions

The cognitive decline after the 3-year follow-up was influenced by the history of stroke and advanced age, while greater MoCA-J score at the baseline was positively associated with subsequent 3 years cognitive decline. The protective factors were the presence of dyslipidemia and a higher educational level. Therefore, these factors are considered important and should be taken into consideration when searching for creative solutions to prevent cognitive decline after stroke in community dwelling older and oldest people.

Delayed Administration of Angiotensin II Type 2 Receptor (AT2R) Agonist Compound 21 Prevents the Development of Post-stroke Cognitive Impairment in Diabetes Through the Modulation of Microglia Polarization

A disabling consequence of stroke is cognitive impairment, occurring in 12%-48% of patients, for which there is no therapy. A critical barrier is the lack of understanding of how post-stroke cognitive impairment (PSCI) develops. While 70% of stroke victims present with comorbid diseases such as diabetes and hypertension, the limited use of comorbid disease models in preclinical research further contributes to this lack of progress. To this end, we used a translational model of diabetes to study the development of PSCI. In addition, we evaluated the application of compound 21 (C21), an angiotensin II Type 2 receptor agonist, for the treatment of PSCI by blinding the treatment assignment, setting strict inclusion criteria, and implementing a delayed administration time point. Diabetes was induced by a high-fat diet (HFD) and low-dose streptozotocin (STZ) combination. Control and diabetic rats were subjected to 1 h middle cerebral artery occlusion (MCAO) or sham surgery. Adhesive removal task (ART) and two-trial Y-maze were utilized to test sensorimotor and cognitive function. Three days post-stroke, rats that met the inclusion criteria were administered C21 or vehicle in drinking water at a dose of 0.12 mg/kg/day for 8 weeks. Samples from freshly harvested brains were analyzed by flow cytometry and immunohistochemistry (IHC). Diabetes exacerbated the development of PSCI and increased inflammation and demyelination. Delayed administration of C21 3 days post-stroke reduced mortality and improved sensorimotor and cognitive deficits. It also reduced inflammation and demyelination through modulation of the M1:M2 ratio in the diabetic animals.

[Frequency and risk factors associated with post-stroke dementia-an observational study on stroke patients without premorbid cognitive impairment]

BACKGROUND

Longitudinal studies on cognitive outcomes after stroke revealed heterogeneous results and the underlying pathology and risk factors for so-called post-stroke dementia are unclear.

OBJECTIVE

To assess long-term cognitive performance changes in patients after the first ischemic stroke and to evaluate possible risk factors for post-stroke dementia.

MATERIAL AND METHODS

In this study 66 clinically mildly affected patients aged 54-87 years without a history of dementia underwent extensive neuropsychological assessment after first ever ischemic stroke and again 6 months after the event (follow-up assessment). Demographic, clinical and paraclinical parameters were assessed as potential predictors for long-term cognitive outcome.

RESULTS

At the group level significant performance improvements were found for most of the neurocognitive domains at the follow-up assessment. The greatest cognitive improvement was found in visuospatial processing. Immediately after stroke 54.5% of patients were considered cognitively impaired (z-scores < -2 in at least 2 neurocognitive domains). At follow-up only 16.7% were considered cognitively impaired according to this criterion and among these only 2 patients (3%) had developed a new, clinically relevant cognitive impairment (i.e. post-stroke dementia). Patients with inferior cognitive performance improvements at follow-up had on average larger brain lesions caused by the stroke as well as a prediabetic metabolic status.

DISCUSSION

The probability of developing a post-stroke dementia syndrome is lower than previously assumed in patients with first ever stroke, with only mild clinical disability and without premorbid cognitive impairment. Long-term cognitive impairment could primarily be determined by the size of the lesioned brain area as well as the premorbid (pre)diabetic status.

Low levels of serum magnesium are associated with poststroke cognitive impairment in ischemic stroke patients

PURPOSE

Population-based studies have revealed a high prevalence of cognitive impairment after stroke. We aimed to determine the impact of serum magnesium (Mg²⁺) levels on the occurrence of poststroke cognitive impairment (PSCI).

PATIENTS AND METHODS

Acute ischemic stroke patients (n = 327) were enrolled in our study and serum Mg²⁺ levels were assessed on admission. The cognitive performance of each patient was evaluated using the Mini-Mental State Examination (MMSE) at a 1-month follow-up visit.

RESULTS

One hundred five (32.1%) patients were diagnosed with PSCI at 1-month poststroke. The serum Mg²⁺ levels in both the PSCI group and the non-PSCI group were significantly lower than those in normal control group (P<0.001). In addition, the PSCI group had lower levels of serum Mg²⁺ compared to the non-PSCI group (P=0.003). In the binary logistic regression analysis, a serum Mg²⁺ level of ≤0.82 mmol/L was significantly associated with an increased risk of developing PSCI by the 1-month follow-up (OR 2.236, 95% CI 1.232-4.058, P=0.008), as was age (OR 1.043, 95% CI 1.014-1.073, P=0.003).

CONCLUSION

Our results demonstrate the existence of a significant association between low levels of serum Mg²⁺ and the occurrence of PSCI 1-month poststroke, and these results suggest that low levels of serum Mg²⁺ on admission may serve as a risk factor for developing PSCI by 1-month poststroke.