Insulin Resistance and Prognosis of Nondiabetic Patients With Ischemic Stroke: The ACROSS-China Study (Abnormal Glucose Regulation in Patients With Acute Stroke Across China)

Insulin resistance and white matter microstructural abnormalities in nondiabetic adult: A population-based study

BACKGROUND

Insulin resistance (IR) is of growing concern yet its association with white matter integrity remains controversial. We aimed to investigate the association between IR and white matter integrity in nondiabetic adults.

METHODS

This cross-sectional analysis was conducted based on the PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study. A total of 1709 nondiabetic community-dwelling adults with available diffusion-weighted imaging based on brain magnetic resonance imaging and completed oral glucose tolerance test were included. IR was measured noninvasively by insulin sensitivity indices (ISI), including ISIcomposite and ISI0,120, as well as homeostasis model assessment of insulin resistance (HOMA-IR). White matter microstructure abnormalities were identified by diffusion-weighted imaging along with tract-based spatial statistical analysis to compare diffusion metrics between groups. The multivariable linear regression models were applied to measure the association between white matter microstructure abnormalities and IR.

RESULTS

A total of 1709 nondiabetic individuals with a mean age of 60.8 ± 6.4 years and 54.1% female were included. We found that IR was associated with a significant increase in mean diffusivity, axial diffusivity, and radial diffusivity extensively in cerebral white matter in regions such as the anterior corona radiata, superior corona radiata, anterior limb of internal capsule, external capsule, and body of corpus callosum. The pattern of associations was more marked for ISIcomposite and ISI0,120. However, the effect of IR on white matter integrity was attenuated after, in addition, adjustment for history of hypertension and cardiovascular disease and antihypertensive medication use.

CONCLUSION

Our findings indicate a significant association between IR and white matter microstructural abnormalities in nondiabetic middle-aged community residents, while these associations were greatly influenced by the history of hypertension and cardiovascular disease, and antihypertensive medication use. Further investigation is needed to clarify the role of IR in white matter integrity, whereas prophylactic strategies of maintaining a low IR status may ameliorate disturbances in white matter integrity.

DATA ACCESSIBILITY STATEMENT

The data that support the findings of this study are available from the corresponding authors upon reasonable request.

Investigation of vascular risk factor control and secondary prevention medication compliance in acute ischemic stroke

Objectives

This study aimed to investigate the management of vascular risk factors, with a specific focus on understanding the various factors affecting risk factor control through an in-depth analysis of clinical data and a longitudinal follow-up of patients who have experienced ischemic strokes.

Methods

A total of 1,572 participants were included in the analysis. We assessed thresholds for blood pressure (BP), low-density lipoprotein cholesterol (LDL-C), and glycated hemoglobin (HbA1c) levels to uncover the contextual conditions and factors affecting vascular risk factor control. Moreover, the study also scrutinized medication compliance at intervals of 3, 6, and 12 months post-onset. Logistic regression was used to adjust for confounding factors.

Results

At 3, 6, and 12 months, BP,LDL, hemoglobin control targets were achieved in 50.7, 51.8, and 50.6%; 51.5, 59.4, and 50.6%; 48.1, 44.0, and 48.4%,respectively. Notably, age was associated with the achievement of BP control (odds ratio [OR], 0.96; 95% confidence intervals [CI], 0.94-0.98; p < 0.0001). Ethnic minorities (OR, 4.23; 95% CI, 1.19-15.09; p = 0.02) and individuals with coronary heart disease (OR, 0.5; 95% CI, 0.3-1.0; p = 0.05) experienced decreased BP control ratios. A previous history of stroke (OR, 1.7; 95% CI, 1.0-2.8; p = 0.03) and unrestricted alcohol consumption (OR, 3.3; 95% CI, 1.0-11.1; p = 0.05) was significantly associated with the achievement of lipid control. Furthermore, lifestyle modifications were significantly correlated with the achievement of BP control (OR, 0.19; 95% CI, 0.12-0.30; p < 0.01), blood glucose control (OR, 0.03; 95% CI, 0.01-0.08; p < 0.01), and blood lipid control (OR, 0.26; 95% CI, 0.16-0.42; p < 0.01). The absence of regular physical activity was associated with lower rates of glycemic (OR, 0.14; 95% CI, 0.06-0.36; p < 0.01) and lipid controls (OR, 0.55; 95% CI, 0.33-0.90; p = 0.01). Over time, overall medication compliance declined.

Conclusion

Within the cohort of patients under medication, the compliance rate concerning vascular risk factors remains unsatisfactory. Attention should be paid to compliance with secondary prevention medications and enhance the control of vascular risk factors, as compliance emerges as the key to effective prevention.

The role of triglyceride-glucose index in the differential diagnosis of atherosclerotic stroke and cardiogenic stroke

OBJECTIVE

This study aims to investigate the role of the triglyceride glucose (TyG) index in differentiating cardiogenic stroke (CE) from large atherosclerotic stroke (LAA).

METHOD

In this retrospective study, patients with acute ischemic stroke were recruited from the First Affiliated Hospital of Soochow University, Lianyungang Second People's Hospital and Lianyungang First People's Hospital. Their general data, medical history and laboratory indicators were collected and TyG index was calculated. Groups were classified by the TyG index quartile to compare the differences between groups. Logistic regression was utilized to assess the relationship between the TyG index and LAA. The receiver operating characteristic curve (ROC) curve was used to evaluate the diagnostic efficiency of the TyG index in differentiating LAA from CE.

RESULT

The study recruited 1149 patients. After adjusting for several identified risk factors, groups TyG-Q2, TyG-Q3, and TyG-Q4 had a higher risk of developing LAA compared to group TyG-Q1(odds ratio (OR) = 1.63,95% confidence interval (CI) = 1.11-2.39, OR = 1.72,95%CI = 1.16-2.55, OR = 2.06,95%CI = 1.36-3.09). TyG has certain diagnostic value in distinguishing LAA from CE(AUC = 0.595, 95%CI0.566-0.623;P<0.001).

CONCLUSION

Summarily, the TyG index has slight significance in the identification of LAA and CE; it is particularly a marker for their preliminary identification.

Adipose tissue specific insulin resistance and prognosis of nondiabetic patients with ischemic stroke

BACKGROUND

Insulin resistance is linked to atherosclerotic cardiovascular diseases and stroke, whereas less is known about adipose tissue specific insulin resistance and outcomes after ischemic stroke. This study aimed to estimate the association between adipose tissue specific insulin resistance and prognosis of nondiabetic patients with ischemic stroke.

METHODS

Patients with ischemic stroke without a history of diabetes mellitus in the Third China National Stroke Registry were included. Adipose tissue specific insulin resistance index (Adipo-IR) was calculated by fasting serum insulin and free fatty acids and categorized into 5 groups according to the quintiles. Outcomes included stroke recurrence (ischemic or hemorrhagic), combined vascular events, all-cause death, and poor outcome (modified Rankin Scale, 3-6) at 12 months after stroke onset. We assessed the association between Adipo-IR and risk of prognosis by multivariable Cox/logistic regression models adjusted for potential covariates.

RESULTS

Among 2,222 patients, 69.0% were men with a mean age of 62.5 years. At 12 months, 185 (8.3%) patients had recurrent stroke, 193 (8.7%) had combined vascular events, 58 (2.6%) died, and 250 (11.5%) had a poor outcome. Compared with patients with the lowest quintile, patients with the second, third, fourth, fifth quintiles of the Adipo-IR were associated with an increased risk of stroke recurrence (hazard ratio [HR], 1.77; 95% CI, 1.04-3.03; P = 0.04; HR, 2.19; 95% CI, 1.30-3.68; P = 0.003; HR, 1.84; 95% CI, 1.06-3.21; P = 0.03; HR, 2.11; 95% CI, 1.20-3.71; P = 0.01, respectively) and marginally associated with an increased risk of combined vascular events ( HR, 1.60; 95%CI, 0.97-2.64; P = 0.07; HR, 1.91; 95% CI, 1.17-3.13; P = 0.01; HR, 1.62; 95% CI, 0.96-2.75; P = 0.07; HR, 1.80; 95% CI, 1.05-3.09; P = 0.03, respectively) at 12 months after adjustment for potential covariates. Adipo-IR was not associated with mortality and poor outcome at 12 months.

CONCLUSIONS

These findings suggest that adipose tissue specific insulin resistance is independently associated with recurrent stroke and combined vascular events after acute ischemic stroke in nondiabetic patients.

Intranasal insulin helps overcome brain insulin deficiency and improves survival and post-stroke cognitive impairment in male mice

Obesity increases the risk for stroke and is associated with worse post-stroke outcomes; however, the mechanisms are poorly understood. Diet-induced obesity leads to insulin resistance and subsequently, brain insulin deficiency. The purpose of this study was to investigate the potential impact of brain insulin deficiency on post-stroke outcomes. To accomplish this, brain insulin levels were assessed in male C57BL/6J (B6) mice placed on either a standard diet or 54% kcal high-fat diet, a known model of insulin resistance. Mice were subjected to either a sham surgery (control) or 30-min middle cerebral artery occlusion to induce an ischemic stroke and administered either intranasal saline (0.9%) or intranasal insulin (1.75 U) twice daily for 5 days beginning on day 1 post-stroke. High-fat diet-induced brain insulin deficiency was associated with increased mortality, neurological and cognitive deficits. On the other hand, increasing brain insulin levels via intranasal insulin improved survival, neurological and cognitive function in high-fat diet mice. Our data suggests that brain insulin deficiency correlates with worse post-stroke outcomes in a diet-induced mouse model of insulin resistance and increasing brain insulin levels may be a therapeutic target to improve stroke recovery.

Association of insulin resistance with intra- and extra-cranial atherosclerotic burden in the nondiabetic community population

AIMS

Few population-based studies have investigated the association between insulin resistance and atherosclerotic burden in intra- and extra-cranial arteries. The purpose of this study is to explore the relationship between insulin resistance and intra- and extra-cranial atherosclerotic burden in community-based nondiabetic participants.

METHODS

This is a cross-sectional analysis from a population-based prospective cohort-PolyvasculaR Evaluation for Cognitive Impairment and vaScular Events (PRECISE) study in China. The homeostasis model assessment of insulin resistance (HOMA-IR) and insulin sensitivity indices (ISI0-120) were stratified by the quartiles, respectively. The atherosclerotic presence of plaques and burden was evaluated by high-resolution MRI. Binary or ordinal logistic regression was performed to assess the association between HOMA-IR or ISI0-120 and the presence and burden of atherosclerosis.

RESULTS

Among the 2754 participants, the mean age was 60.9 ± 6.6 years, and 1296 (47.1%) were males. Compared with the lowest quartile of HOMR-IR, the highest quartile of HOMA-IR (indicating a higher level of insulin resistance) was associated with an increased presence of plaques (OR:1.54, 95% CI:1.14-2.08), and atherosclerotic burden (OR:1.53, 95%CI:1.14-2.07) in intracranial arteries. Meanwhile, we observed a similar relationship between HOMA-IR and the presence or burden in extracranial atherosclerosis. The first (indicating a higher level of insulin resistance) quartiles of ISI0-120 were associated with the intracranial plaques (Q1, OR:1.56, 95%CI:1.16-2.11) and atherosclerotic burden (Q1, OR:1.57, 95%CI:1.17-2.12), but not extracranial plaques or atherosclerotic burden, compared with the fourth quartile of ISI0-120.

CONCLUSIONS

Insulin resistance was associated with an increased intra-and extra-cranial atherosclerotic burden in the nondiabetic elderly Chinese population.

Insulin resistance estimated by estimated glucose disposal rate predicts outcomes in acute ischemic stroke patients

BACKGROUND

Estimated glucose disposal rate (eGDR), a simple and noninvasive measure of insulin resistance, has been proven to be an independent risk factor for first-time stroke and all-cause mortality. In this study, we aimed to investigate the associations between eGDR and the stroke outcome in patients with first-time acute ischemic stroke (AIS).

METHODS

We included first-time AIS patients with available data on eGDR in the China National Stroke Registry III (CNSR-III), and divided the subjects into lower eGDR group (eGDR ≤ 6 mg/kg/min) and higher eGDR group (eGDR > 6 mg/kg/min). The primary outcome was excellent functional outcome (modified Rankin Scale score 0-1) at 3 months. Secondary outcomes included stroke recurrence and favorable functional outcome (modified Rankin Scale score 0-2) at 3 months, and functional outcome and combined vascular event at one year. Univariate and multivariate analyses were performed to evaluate the association between eGDR and outcomes.

RESULTS

A total of 6,271 patients with AIS were included in this study. The median values of eGDR in lower and higher eGDR group were 5.0 mg/kg/min (interquartile range, 4.2-5.6) and 7.6 mg/kg/min (interquartile range, 6.8-9.6), respectively. Patients with higher eGDR were significantly associated with higher incidence of excellent functional outcome (adjusted odds ratio, 1.24; 95% confidence interval, 1.06-1.45; P < 0.01) at 3 months and favorable (adjusted odds ratio, 1.55; 95% confidence interval, 1.24-1.93; P < 0.01) and excellent (adjusted odds ratio, 1.28; 95% confidence interval, 1.08-1.51; P < 0.01) functional outcome at one year. However, there was no significant difference in stroke recurrence between these two groups at 3 months (adjusted odds ratio, 0.81; 95% confidence interval, 0.61-1.06; P = 0.12) and one year (adjusted odds ratio, 0.91; 95% confidence interval, 0.73-1.14; P = 0.41).

CONCLUSION

eGDR is a predictor of functional outcome in patients with AIS, independent of traditional cardiovascular predictors.

Triglyceride-glucose index predicts death in patients with stroke younger than 65

Background

The triglyceride-glucose index (TGI), a reliable surrogate indicator of insulin resistance (IR), has been proven to be a predictor of the incidence of ischemic stroke. The role of TGI in predicting the outcomes of stroke patients remains controversial. Susceptibility to IR-related diseases varies among patients of different ages. The study aims to evaluate the predictive value of TGI levels on clinical outcomes of patients with ischemic stroke of different ages.

Method

This was a retrospective cohort study including patients with ischemic stroke in the Department of Neurology at West China Hospital. TGI was calculated as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. The patients were subdivided into 3 tertiles according to TGI levels. Multivariate logistic regression analyses were conducted to estimate the association between TGI levels and post-stroke outcomes among the whole patients, younger patients (<65), and older patients (>=65). The outcomes included death and unfavorable functional outcome (modified Rankin scale score 3-6) at 3 and 12 months after stroke.

Results

A total of 3,704 patients (men, 65.08%, mean age, 61.44 ± 14.15; women 34.92%, mean age, 65.70 ± 13.69) were enrolled in this study. TGI levels were not associated with 3 month or 12 month death in the whole patients. Patients with higher TGI levels (T2 and T3) had a higher risk of 3 month death than those had lower TGI levels (T1) in the younger group (T2 vs. T1: OR 2.64, 95% CI 1.03-6.79, p = 0.043; T3 vs. T1: OR 2.69, 95% CI 1.00-7.10, p = 0.049) but not in the older group. Additionally, Kaplan-Meier estimate analysis illustrated that the 12 month death risk was significantly higher in the group with the highest TGI among younger patients (p for log-rank test = 0.028) but not among older patients. There was an interactive effect between TGI and age on 3 month death (p for interaction = 0.013) and 12 month death (p for interaction = 0.027). However, TGI was not associated with unfavorable functional outcome at 3 month or 12 month after stroke.

Conclusion

Elevated TGI independently predicts death at 3 months and 12 months in patients under 65 with ischemic stroke. Regulating TGI is expected to be an approach to enhance prognosis in young individuals affected by ischemic stroke.

The change of triglyceride-glucose index may predict incidence of stroke in the general population over 45 years old

BACKGROUND

Stroke has been found to be highly correlated with the triglyceride-glucose (TyG) index. The relation between the TyG index changes and stroke, however, has seldom been reported, and current researches mentioning the TyG index concentrate on individual values. We aimed to investigate whether the level and the change of TyG index was associated with the incidence of stroke.

METHODS

Sociodemographic, medical background, anthropometric and laboratory information were retrospectively collected. Classification was conducted using k-means clustering analysis. Logistic regressions were to determine the relationship between different classes with changes in the TyG index and incidence of stroke, taking the class with the smallest change as a reference. Meanwhile, restricted cubic spline regression was applied to examine the links of cumulative TyG index and stroke.

RESULTS

369 (7.8%) of 4710 participants had a stroke during 3 years. Compared to class 1 with the best control of the TyG Index, the OR for class 2 with good control was 1.427 (95% CI, 1.051-1.938), the OR for class 3 with moderate control was 1.714 (95% CI, 1.245-2.359), the OR for class 4 with worse control was 1.814 (95% CI, 1.257-2.617), and the OR for class 5 with consistently high levels was 2.161 (95% CI, 1.446-3.228). However, after adjusting for multiple factors, only class 3 still had an association with stroke (OR 1.430, 95%CI, 1.022-2.000). The relation between the cumulative TyG index and stroke was linear in restricted cubic spline regression. In subgroup analysis, similar results were shown in participants without diabetes or dyslipidemia. There is neither additive nor multiplicative interaction between TyG index class and covariates.

CONCLUSION

A constant higher level with worst control in TyG index indicated a higher risk of stroke.

New stress-induced hyperglycaemia markers predict prognosis in patients after mechanical thrombectomy

OBJECTIVE

Stress-induced hyperglycaemia (SIH) is a frequent phenomenon that occurs in patients with acute ischaemic stroke. The aim of this study was to investigate the relationship between SIH and the prognosis of mechanical thrombectomy (MT) patients according to the stress hyperglycemia ratio (SHR) and glycaemic gap (GG) indicators, as well as explore its relationship with haemorrhagic transformation (HT).

METHODS

Patients were enrolled from January 2019 to September 2021 in our centre. SHR was calculated as fasting blood glucose divided by the A1c-derived average glucose (ADAG). GG was calculated as fasting blood glucose minus ADAG. Logistic regression was used to analyse SHR, GG with outcome and HT.

RESULTS

A total of 423 patients were enrolled in the study. The incidence of SIH was as follows: 191/423 of patients with SHR > 0.89, 169/423 of patients with GG > -0.53. SHR > 0.89 (OR: 2.247, 95% CI: 1.344-3.756, P = 0.002) and GG>-0.53 (OR: 2.305, 95% CI: 1.370-3.879, P = 0.002) were both associated with poor outcomes (modified Rankin Scale > 2) at Day 90 and an increase risk of HT. Additionlly, receiver operating characteristic curves were used to assess the predictive performance of the SHR and GG on outcomes. The area under the curve for SHR to predict poor outcomes was 0.691, with an optimal cut-off value of 0.89. The area under the curve for GG was 0.682, with an optimal cut-off value of -0.53.

CONCLUSION

High SHR and high GG are strongly associated with poor 90-day prognosis in MT patients and an increased risk of HT.

Mediation of Systemic Inflammation on Insulin Resistance and Prognosis of Nondiabetic Patients With Ischemic Stroke

BACKGROUND

Insulin resistance is associated with stroke recurrence and poor functional outcomes of nondiabetic patients with ischemic stroke. The study aimed to investigate whether the association between insulin resistance and the prognosis of nondiabetic patients with ischemic stroke was mediated by systematic inflammation.

METHODS

Patients with ischemic stroke but without a history of diabetes who were enrolled in CNSR-III (Third China National Stroke Registry) were included in the study and followed up for 1 year after stroke onset. Insulin resistance was determined by using the homeostasis model assessment for insulin resistance (HOMA-IR) method. hs-CRP (high-sensitivity C-reactive protein) and Lp-PLA₂ (lipoprotein-associated phospholipase A₂) activity were measured at baseline. The primary outcome was stroke recurrence, and other outcomes included composite vascular events, mortality, and poor functional outcome (modified Rankin Scale score, 3-6). Multivariable Cox or logistic regression analyses were performed to estimate the association between HOMA-IR and the study outcomes. A mediation analysis was performed to examine the relationship between insulin resistance and the study outcomes mediated by systemic inflammation.

RESULTS

Among a total of 3808 nondiabetic patients with ischemic stroke who were included in the study, the median HOMA-IR was 1.79 (interquartile range, 1.05-2.97). After adjustments for potential confounders, higher HOMA-IR quartiles were associated with higher risks of stroke recurrence, ischemic stroke, and composite vascular events, especially in the large artery atherosclerosis subtype. hs-CRP partially mediated the association between the HOMA-IR index and the prognosis of ischemic stroke (mediation proportion, 5.9% for stroke recurrence and 7.5% for composite vascular events). No evidence of Lp-PLA₂ activity mediating the association of insulin resistance with stroke outcomes was observed.

CONCLUSIONS

Our study found that insulin resistance was associated with poor clinical outcomes in nondiabetic patients with ischemic stroke, which was partially mediated by hs-CRP with a modest amount.

The Pre-Stroke Induction and Normalization of Insulin Resistance Respectively Worsens and Improves Functional Recovery

Type 2 diabetes (T2D) impairs post-stroke recovery, and the underlying mechanisms are unknown. Insulin resistance (IR), a T2D hallmark that is also closely linked to aging, has been associated with impaired post-stroke recovery. However, whether IR worsens stroke recovery is unknown. We addressed this question in mouse models where early IR, with or without hyperglycemia, was induced by chronic high-fat diet feeding or sucrose supplementation in the drinking water, respectively. Furthermore, we used 10-month-old mice, spontaneously developing IR but not hyperglycemia, where IR was normalized pharmacologically pre-stroke with Rosiglitazone. Stroke was induced by transient middle cerebral artery occlusion and recovery was assessed by sensorimotor tests. Neuronal survival, neuroinflammation and the density of striatal cholinergic interneurons were also assessed by immunohistochemistry/quantitative microscopy. Pre-stroke induction and normalization of IR, respectively, worsened and improved post-stroke neurological recovery. Moreover, our data indicate a potential association of this impaired recovery with exacerbated neuroinflammation and a decreased density of striatal cholinergic interneurons. The global diabetes epidemic and population aging are dramatically increasing the percentage of people in need of post-stroke treatment/care. Our results suggest that future clinical studies should target pre-stroke IR to reduce stroke sequelae in both diabetics and elderly people with prediabetes.

Triglyceride-glucose index and short-term functional outcome and in-hospital mortality in patients with ischemic stroke

BACKGROUND AND AIMS

The triglyceride-glucose (TyG) index has been demonstrated as an independent marker of ischemic stroke. Whether TyG index predicts short-term outcomes in patients with ischemic stroke remains uncertain. The aim of the study was to investigate the early prognosis value of TyG index in ischemic stroke patients.

METHODS AND RESULTS

A total of 3216 acute ischemic stroke patients from 22 hospitals were included in this analysis. The TyG index was calculated as ln (fasting triglyceride [mg/dL] × fasting glucose [mg/dL]/2). Logistic regression model was performed to estimate the relationship between TyG index and unfavorable functional outcome of death or disability (modified Rankin Scale score of 4-6) at discharge. Risk reclassification with TyG index to predict unfavorable functional outcome was analyzed. During hospitalization, 748 patients (23.3%) experienced poor functional outcome and 105 patients (3.3%) died from all causes. The multivariable adjusted odds ratios for the highest versus lowest quartile of TyG index was 1.62 (95% CI 1.15-2.29) for unfavorable functional outcome at discharge. The addition of TyG index to the conventional model improved the risk reclassification (net reclassification improvement 10.37%; integrated discrimination improvement 0.27%; both p < 0.05) for poor functional outcome. Moreover, TyG index was associated with an odds ratio (95% CI) of 1.26 (1.02-1.55) for an ordinal shift in mRS score and 2.49 (1.21-5.12) for in-hospital mortality.

CONCLUSIONS

Higher TyG index was associated with higher risk of unfavorable functional outcome at discharge and in-hospital mortality, implicating the significant short-term prognostic effect of TyG index in patients with ischemic stroke.

The impact of triglyceride-glucose index on ischemic stroke: a systematic review and meta-analysis

BACKGROUND

Strokes significantly impair quality of life and incur high economic and societal burdens. The triglyceride and glucose (TyG) index is a biochemical marker of insulin resistance (IR) and may have important value in the prediction of strokes, especially ischemic stroke (IS). Our study aims to investigate the relationship between TyG index and IS and ascertain whether TyG index is independently associated with IS adverse outcomes.

METHODS

The Cochrane, Embase, Medline, Web of Science, PubMed, and other relevant English databases and related websites were systematically searched for articles on ''TyG index'' and "stroke" published from inception to April 4, 2022. We reviewed the available literature on the TyG index and its relation to predicting IS occurrence in the general population and adverse clinical outcomes. We calculated odds ratios (OR) of TyG index and its predictability of IS occurrence and adverse outcomes. Statistical analyses were performed using the Meta Package in STATA, version 12.0.

RESULTS

A total of 18 studies and 592,635 patients were included in our analysis. The pooled effect values of all stroke types showed that higher TyG index was associated with increased the risk of IS in the general population (OR 1.37; 95% CI 1.22-1.54) in a total sample of 554,334 cases with a high level of heterogeneity (P = 0.000, I² = 74.10%). In addition, compared to IS patients with a lower TyG index, IS patients with a higher TyG index was associated with higher risk of stroke recurrence (OR: 1.50; 95% CI 1.19-1.89) and increased risk of mortality (OR 1.40 95% CI 1.14-1.71). No correlation was found in the effect value combinations of poor functional outcomes (OR 1.12; 95% CI 0.88-1.43) and neurological worsening (OR: 1.76; 95% CI 0.79-3.95) in a total sample of 38,301 cases with a high level of heterogeneity (P = 0.000; I² = 77.20%).

CONCLUSIONS

TyG index has potential value in optimizing risk stratification for IS in the general population. Furthermore, there is a significant association between high TyG index and many adverse outcomes of stroke, especially stroke recurrence and high mortality. Future studies should focus on multi-center and multi-regional designs in order to further explore the relationship between IS and TyG index.

Prognostic Value of Stress Hyperglycaemia Ratio in Young Patients with Ischaemic Stroke or Transient Ischaemic Attack

INTRODUCTION

Stress hyperglycaemia is common in stroke. Recently, the stress hyperglycaemia ratio (SHR) has been proposed as a novel marker for stress hyperglycaemia and found to be associated with adverse outcomes in many diseases. However, data regarding the impact of the SHR on ischaemic stroke, especially in young adults, are limited. Therefore, the aim of this study was to investigate whether the SHR is associated with stroke severity and adverse outcomes in young adults with ischaemic stroke or transient ischaemic attack (TIA).

METHODS

We retrospectively recruited patients aged 18-45 years with acute ischaemic stroke or TIA. The SHR was calculated as fasting blood glucose (FBG) divided by glycated haemoglobin. The primary and secondary outcomes were 90-day poor functional outcomes and stroke severity on admission, respectively. Multivariable logistic regression, restricted cubic spline models, and subgroup analysis were performed to validate the relationship between the SHR and ischaemic stroke or TIA in young adults.

RESULTS

A total of 687 young adults (mean age 36.9 years) were recruited. Among them, 119 (17.3%) patients had prior diabetes, and 568 (82.7%) did not. The SHR was significantly associated with stroke severity and poor functional outcome. Compared with patients with lower SHR values, patients with higher SHR values were more likely to have moderate-to-severe stroke. The multivariable-adjusted OR (95% CI) was 1.70 (1.21-2.39) after adjusting for all potential confounders excluding FBG and 1.50 (1.03-2.17) after FBG adjustment. The restricted cubic spline showed a J-shaped association between the SHR and moderate-to-severe stroke. Compared with patients with lower SHR values, patients with higher SHR values were more likely to have poor functional outcome at 90-day follow-up. The multivariable-adjusted OR (95% CI) was 1.95 (1.12-3.41) after adjusting for all potential confounders excluding FBG and 1.84 (1.01-3.36) after FBG adjustment. A J-shaped association was found between the SHR and poor functional outcomes at the 90-day follow-up. In the subgroup analysis, SHR was independently associated with more severe stroke (OR, 1.79, 95% CI, 1.18-2.72) and poor functional outcomes (OR, 2.11, 95% CI, 1.32-3.35) in nondiabetic patients but not in diabetic patients in multivariate logistic analysis. Despite this, the interaction effects of prior diabetes on the association between the SHR and stroke severity and poor functional outcomes did not reach statistical significance.

CONCLUSION

The SHR is independently related to more severe stroke and an increased risk of poor functional outcomes among young adults with ischaemic stroke or TIA.

Study on insulin resistance and ischemic cerebrovascular disease: A bibliometric analysis via CiteSpace

Background

It is reported that insulin resistance widely exists in non-diabetic patients with a recent history of transient ischemic attack (TIA) or ischemic stroke. There is currently strong evidence to prove the bidirectional effect of glucose metabolism disorders and stroke events. Therefore, it is necessary to retrospectively tease out the current status, hotspots, and frontiers of insulin resistance and ischemic cerebrovascular disease through CiteSpace.

Materials and methods

We searched the Web of Science (WOS) for studies related to insulin resistance and ischemic cerebrovascular disease from 1999 to April 2022, then downloaded the data into CiteSpace to generate a knowledge visualization map.

Results

A total of 1,500 publications relevant to insulin resistance and ischemic cerebrovascular disease were retrieved. The USA had the most articles on this topic, followed by PEOPLES R CHINA and JAPAN. WALTER N KERNAN was the most prolific author, whose research mainly focused on insulin resistance intervention after stroke (IRIS) trial. The most common keywords were myocardial ischemia, metabolic syndrome, ischemic stroke, cerebral ischemia, association, oxidative stress, inflammation, and adipose tissue. Major ongoing research trends include three aspects: (1) the association between insulin resistance and ischemic cerebrovascular disease in non-diabetic patients, (2) the intrinsic pathological mechanism between insulin resistance and ischemic cerebrovascular disease, and (3) early intervention of insulin resistance to improve the prognosis of stroke.

Conclusion

The results of this bibliometric study provide the current status and trends of clinical research publications in the field of insulin resistance and ischemic cerebrovascular disease. Insulin resistance is strongly associated with the occurrence of ischemic stroke, early neurological deterioration in stroke patients, post-stroke depression, and cerebral small vessel disease. Early treatment of insulin resistance can be an effective way to prevent the onset of ischemic stroke and improve stroke prognosis. This study may help researchers to identify hot topics and explore new research directions.

Association of triglyceride-glucose index with ischemic stroke recurrence in nondiabetic patients with small vessel occlusion: a multicenter hospital-based prospective cohort study

BACKGROUND

Triglyceride-glucose (TyG) index is a simple and reliable surrogate marker of insulin resistance. Elevated TyG index was related to stroke recurrence. This study aimed to explore the associations between TyG index with ischemic stroke recurrence in nondiabetic patients with small vessel occlusion.

METHODS

From November 1, 2016 to February 28, 2021, consecutive acute ischemic stroke patients admitted within 1 week after onset were screened. The stroke mechanism was determined based on medical history, laboratory examinations, cardiac examinations, vascular examinations and neuroimaging. Nondiabetic patients with small vessel occlusion were enrolled and followed up for 1 year. The primary outcome was ischemic stroke recurrence. Logistic regression and Kaplan-Meier survival curve were used to analyze the association of the TyG index and stroke recurrence.

RESULTS

A total of 6100 acute ischemic stroke patients were screened, with 1970 nondiabetic patients with small vessel occlusion included and divided into 4 groups according to the TyG index quartiles (Q1: < 8.20; Q2: 8.20-8.53; Q3: 8.54-8.92; Q4: > 8.92). There were significant differences in age, body mass index, systolic blood pression, diastolic blood pressure, lipid-lowering agents, infarct location, fasting blood glucose, total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, uric acid, and stroke recurrence among the 4 groups. In the multi-adjusted models, compared to Q1 of the TyG index, the odds ratio for Q4 of the TyG index for stroke recurrence was 3.100 (1.366-8.019). The Kaplan-Meier survival (ischemic stroke-free) curves by quartiles of the TyG index also showed statistically significant differences (log-rank test, P = 0.004).

CONCLUSIONS

Our findings suggested that the TyG index was associated with ischemic stroke recurrence in nondiabetic patients with small vessel occlusion, and it could be a valuable biomarker for assessing the risk of ischemic stroke recurrence in these patients.

The mediating function of obesity on endocrine-disrupting chemicals and insulin resistance in children

OBJECTIVES

To explore the association of endocrine-disrupting chemicals (EDCs) with insulin resistance (IR) in children as well as whether obesity played a mediation role between EDCs and IR.

METHODS

In this cross-sectional study, the data of 878 subjects were included, and divided into the non-IR group (n=501) and IR group (n=377). The associations of EDC and IR, obesity, abdominal obesity were shown by restricted cubic spline (RCS). Univariate and multivariable logistic analysis were applied to explore the associations between EDCs and IR as well as EDCs and obesity, respectively. Bootstrap coefficient product was used to analyze the medication effect of obesity on EDCs and IR.

RESULTS

RCS showed that increase of benzophenone-3 (BP-3) level was associated with increased risk of IR, obesity and abdominal obesity. After adjusting for confounders, BP-3>100 ng/mL was a risk factor for IR (OR=1.42, 95%CI: 1.11-1.81). In the adjusted model, we found BP-3>100 ng/mL was a risk factor for both obesity (OR=1.52, 95%CI: 1.13-2.04) and abdominal obesity (OR=1.68, 95%CI: 1.11-2.54). The indirect effect of obesity as a mediator on the relationship between BP-3 and IR was 0.038 (95%CI: 0.016-0.090) and the direct effect of obesity as a mediator on the relationship between BP-3 and IR was 0.077 (95%CI: 0.001-0.160). As for abdominal obesity, the indirect effect of it on the relationship between BP-3 and IR was 0.039 (95%CI: 0.007-0.070).

CONCLUSIONS

BP-3 level might be a risk factor for IR and obesity in children, and obesity was a mediator on the relationship between BP-3 and IR in children.

Insulin Resistance and Vitamin D Deficiency: A Link Beyond the Appearances

Vitamin D is a steroid hormone that plays a key role in the regulation of body homeostasis, including cardiovascular function. Although the chronic deficiency of vitamin D is associated with cardiovascular risk factors, as well as with an adverse prognosis, randomized controlled trials have failed in demonstrating that dietary vitamin D supplementation could ameliorate the prognosis of patients with cardiovascular diseases, and suggested that vitamin D deficiency is the expression of the effects of other determinants of cardiovascular risk. Thus, the supplementation of vitamin D is not sufficient to improve the cardiovascular risk profile and prognosis. Insulin resistance is a complex phenomenon that plays a key role in the pathogenesis of conventional cardiovascular risk factors. Interestingly, defects of vitamin D and insulin resistance have a superimposable epidemiological distribution. According to the common view, Insulin resistance is considered the direct or indirect consequence of vitamin D deficiency. However, it is also reasonable to speculate that the deficit or the impaired action of vitamin D, in some circumstances, could be the result of the same pathogenic mechanisms responsible of insulin resistance development. In this case, vitamin D deficiency could be considered an epiphenomenon of insulin resistance. Insulin resistance is a reversible condition, being possibly ameliorated by physical activity and hypocaloric diets. Notably, both physical exercise and energy-restricted dietary regimens are associated with an increase of vitamin D levels. These findings indicate that improving insulin resistance condition is a necessary step to ameliorate vitamin D supplementation-based strategies in cardiovascular prevention.

Association of triglyceride-glucose index and stroke recurrence among nondiabetic patients with acute ischemic stroke

Backgroud and purpose

Triglyceride-glucose (TyG) index has been considered a surrogate marker of insulin resistance. We investigated the association between TyG index and stroke recurrence and compared the effectiveness of TyG index with homeostasis model assessment of insulin resistance (HOMA-IR) in predicting stroke recurrence and death in nondiabetic acute ischemic stroke patients.

Methods

Nondiabetic acute ischemic stroke patients from the ACROSS-China (Abnormal Glucose Regulation in Patients with Acute Stroke across China) registry were included. TyG index was performed and classified into four groups by quartiles. The outcomes were stroke recurrence and death within 1 year. The association between TyG index and the risk of stroke recurrence and death were analyzed by Cox regression models. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the prediction of TyG index and HOMA-IR for stroke recurrence and death. Delong test was used for comparing the differences between area under the curve (AUC) of TyG index and HOMA-IR.

Results

Among the 1226 patients included, the median (interquartile range) of TyG index was 5.8 (5.5–6.2). Both the third and fourth quartiles of TyG index were associated with an increased risk of stroke recurrence (adjusted hazard ratio 2.04, 95% confidence interval 1.26–3.31; adjusted hazard ratio 1.86, 95% confidence interval 1.13–3.06). Patients with fourth quartiles of TyG index were associated with a higher mortality risk (adjusted hazard ratio, 2.91; 95% confidence interval, 1.62–2.53). Regarding stroke recurrence within 1 year, the AUC (95% confidence interval) of the ROC curve for the TyG index was similar to that of the HOMA-IR[0.56 (0.52–0.61) vs 0.57 (0.52–0.61); P = 0.93]. Regarding death within 1 year, the AUCs (95% confidence interval) of the ROC curve for the TyG index and HOMA-IR were 0.55 (0.50–0.61) and 0.59 (0.53–0.64), respectively (P = 0.32).

Conclusions

Elevated TyG index was associated with an increased risk of stroke recurrence and death. However, neither of TyG nor HOMA-IR can be a qualified predictor of stroke recurrence and death in nondiabetic acute ischemic stroke patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02588-3.

Triglyceride-Glucose Index and Intravenous Thrombolysis Outcomes for Acute Ischemic Stroke: A Multicenter Prospective–Cohort Study

Background

The triglyceride-glucose (TyG) index has recently been proposed as a reliable marker of insulin resistance. There is insufficient evidence to verify that the TyG index is correlated with functional outcomes and hemorrhagic transformation and in patients with stroke treated with intravenous thrombolysis (IVT).

Methods

We designed a multicenter cohort study, which enrolled patients with acute ischemic stroke treated with IVT between December 2004 and December 2016. The TyG index was divided into tertiles and calculated on a continuous scale. Unfavorable functional outcomes were defined by the modified Rankin Scale of 3–6 at 90 days and the incident rates of symptomatic intracranial hemorrhage (SICH) within 36 h of IVT onset were surveyed. Stroke severity was defined as mild (4–8), moderate (9–15), or high (≥16) based on the National Institutes of Health Stroke Scale (NIHSS) scores.

Results

Among 914 enrolled patients, the tertiles of the TyG index were 8.48 for T1, 8.48–9.04 for T2, and 9.04 for T3. T3 showed an increased risk of unfavorable functional outcomes at 90 days [odds ratio (OR): 1.76; P = 0.0132]. The TyG index was significantly associated with unfavorable functional outcomes at 90 days (OR: 1.32; P = 0.0431 per unit increase). No association was found between the TyG index and SICH. These findings were applicable for T3 with stroke of moderate (OR, 2.35; P = 0.0465) and high severity (OR: 2.57, P = 0.0440) patients with stroke.

Conclusion

This study supports the strong association between the increased TyG index and increased unfavorable functional outcomes at 90 days in patients with acute ischemic stroke treated with IVT. These findings were found to be robust in patients with moderate and high stroke severity.

Association of triglyceride-glucose index with clinical outcomes in patients with acute ischemic stroke receiving intravenous thrombolysis

Intravenous tissue plasminogen activator (tPA) remains the cornerstone of recanalization therapy for acute ischemic stroke (AIS), albeit with varying degrees of response. The triglyceride-glucose (TyG) index is a novel marker of insulin resistance, but association with outcomes among AIS patients who have received tPA has not been well elucidated. We studied 698 patients with AIS who received tPA from 2006 to 2018 in a comprehensive stroke centre. TyG index was calculated using the formula: ln[fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. TyG index was significantly lower in patients that survived at 90-days than those who died (8.61 [Interquartile Range: 8.27-8.99] vs 8.76 [interquartile range: 8.39-9.40], p = 0.007). In multivariate analysis, TyG index was significantly associated with 90-day mortality (OR: 2.12, 95% CI: 1.39-3.23, p = 0.001), poor functional outcome (OR: 1.41 95% CI: 1.05-1.90, p = 0.022), and negatively associated with early neurological improvement (ENI) (OR: 0.68, 95% CI: 0.52-0.89, p = 0.004). There was no association between TyG index and symptomatic intracranial hemorrhage. 'High TyG' (defined by TyG index ≥ 9.15) was associated with mortality, poor functional outcomes and no ENI. In conclusion, the TyG index, a measure of insulin resistance, was significantly associated with poorer clinical outcomes in AIS patients who received tPA.

Impact of Pancreatic β-Cell Function on Clopidogrel Responsiveness and Outcomes in Chinese Nondiabetic Patients Undergoing Elective Percutaneous Coronary Intervention

PURPOSE

Insulin resistance and β-cell dysfunction are fundamental defects contributing to type 2 diabetes development. Prior studies indicated that insulin resistance may be correlated with low responsiveness to clopidogrel. This study aimed to investigate the effects of β-cell function on clopidogrel-induced platelet P2Y12 inhibition and the clinical outcomes of nondiabetic patients undergoing elective percutaneous coronary intervention (PCI).

METHODS

Patients scheduled to undergo elective PCI and receive clopidogrel in addition to aspirin were recruited for this study. Homeostatic model assessment 2 of β-cell function (HOMA2-β%) was used to classify participants into quartiles. Thromboelastography (TEG) was used to calculate the quantitative platelet inhibition rate to assess clopidogrel-induced antiplatelet reactivity. The clinical outcome was major adverse cardiovascular and cerebrovascular events (MACCEs).

RESULTS

Of the 784 participants evaluated, 21.3% of them (169 of 784) had low responsiveness to clopidogrel. According to multivariate linear regression analysis, the first quartile of HOMA2-β% (19.9-78.1), indicating greater β-cell dysfunction, was independently associated with low responsiveness to clopidogrel compared with the fourth quartile (126.8-326.2) after adjustment for potential covariates [odds ratio 2.140, 95% confidence interval (CI) (1.336 to 3.570), P = 0.038]. In addition, at one year, the first quartile of HOMA2-β% was associated with an increased risk of 1-year MACCE occurrence compared with the fourth quartile [adjusted hazard ratio 4.989, 95% CI (1.571 to 15.845), P = 0.006].

CONCLUSION

Increased β-cell dysfunction, indicated by a low HOMA2-β%, was associated with low responsiveness to clopidogrel and an increased risk of one-year MACCEs in nondiabetic patients undergoing elective PCI.

Chronic binge alcohol and ovariectomy-mediated impaired insulin responsiveness in SIV-infected female rhesus macaques

Aging people living with HIV (PLWH), especially postmenopausal women may be at higher risk of comorbidities associated with HIV, antiretroviral therapy (ART), hypogonadism, and at-risk alcohol use. Our studies in simian immunodeficiency virus (SIV)-infected male macaques demonstrated that chronic binge alcohol (CBA) reduced acute insulin response to glucose (AIRG), and at-risk alcohol use decreased HOMA-β in PLWH. The objective of this study was to examine the impact of ovariectomy (OVX) on glucose-insulin dynamics and integrity of pancreatic endocrine function in CBA/SIV-infected female macaques. Female macaques were administered CBA (12-15 g/kg/wk) or isovolumetric water (VEH) intragastrically. Three months after initiation of CBA/VEH administration, all macaques were infected with SIVmac251, and initiated on antiretroviral therapy (ART) 2.5 mo postinfection. After 1 mo of ART, macaques were randomized to OVX or sham surgeries (n = 7 or 8/group), and euthanized 8 mo post-OVX (study endpoint). Frequently sampled intravenous glucose tolerance tests (FSIVGTT) were performed at selected time points. Pancreatic gene expression and islet morphology were determined at study endpoint. There was a main effect of CBA to decrease AIRG at Pre-SIV and study endpoint. There were no statistically significant OVX effects on AIRG (P = 0.06). CBA and OVX decreased the expression of pancreatic markers of insulin docking and release. OVX increased endoplasmic stress markers. CBA but not OVX impaired glucose-insulin expression dynamics in SIV-infected female macaques. Both CBA and OVX altered integrity of pancreatic endocrine function. These findings suggest increased vulnerability of PLWH to overt metabolic dysfunction that may be exacerbated by alcohol use and ovarian hormone loss.

Predictive Value of Insulin Resistance as Determined by Homeostasis Model Assessment in Acute Ischemic Stroke Patients: A Systematic Review and Meta-Analysis

Studies on association between homeostasis model assessment of insulin resistance (HOMA-IR) and adverse outcomes have yielded conflicting results in patients with acute ischemic stroke (AIS). This meta-analysis aimed to assess the predictive value of HOMA-IR in AIS patients. Two authors comprehensively searched PubMed and Embase databases until February 28, 2021. All observational studies investigating the association between HOMA-IR and adverse outcomes in AIS patients were included. Outcome measures were poor functional outcome (Modified Rankin Scale≥3), all-cause mortality, stroke recurrence, and neurologic worsening. Seven studies (eight articles) involving 8330 AIS patients were identified. For the highest versus lowest HOMA-IR, the pooled risk ratio (RR) of poor functional outcome was 2.55 (95% CI 1.76-3.70) after adjustment of conventional confounding factors. In addition, elevated HOMA-IR was associated with higher risk of neurologic worsening (RR 1.93; 95% CI 1.15-3.26). However, there were conflicting findings on the association of HOMA-IR with stroke recurrence and all-cause mortality. This meta-analysis confirms that HOMA-IR is significantly associated with an increased risk of poor functional outcome in patients with AIS. However, interpretation of the results of mortality, stroke recurrence, and neurologic worsening should be done with caution due to small number of studies available.

Triglyceride glucose index influences platelet reactivity in acute ischemic stroke patients

Aim

Insulin resistance was reported to increase the risk of ischemic stroke, which can be assessed by the triglyceride glucose (TyG) index. However, it remains unclear whether the TyG index influences the platelet reactivity during the treatment of ischemic patients.

Methods

Ischemic stroke patients receiving dual antiplatelet therapy (DAPT) within 48 h onset were consecutively included. The TyG index was calculated as ln (fasting triglyceride [mg/dL] × fasting glucose [mg/dL]/2). The top quartile of TyG index was defined as insulin resistance. The platelet reactivity was assessed by thromboelastography. The platelet inhibition rate induced by arachidonic acid (AA) or adenosine diphosphate (ADP) was used to confirm the high residual on-treatment platelet reactivity (HRPR) to aspirin or clopidogrel, respectively. The association between TyG index and platelet reactivity was assessed by Kruskal–Wallis test. The independent risk factors of HRPR were determined by multivariate logistic regression analysis.

Results

A total of 1002 patients were included and divided into 4 groups by quartiles of the TyG index (< 2.02; 2.02–2.27; 2.27–2.52; ≥2.52). The findings demonstrated that the maximum intensity of the clot increased, but the AA-induced platelet inhibition rate decreased, depending on the TyG index quartiles. No significant difference was found in the ADP-induced platelet inhibition rate among groups. The prevalence of aspirin HRPR increased depending on the TyG index quartile. Unlike the non-insulin resistance group, the insulin resistance group was independently associated with aspirin HRPR (OR = 1.689, 95% CI 1.14 to 2.51, P = 0.009).

Conclusions

In acute ischemic stroke patients taking DAPT, the elevation of the TyG index is associated with enhanced platelet reactivity and higher prevalence of aspirin HRPR. Insulin resistance assessed by the TyG index could be an independent risk factor for aspirin HRPR.

Baseline or 90-day fibrinogen levels and long-term outcomes after ischemic stroke or TIA: Results from the China national stroke registry Ⅲ

BACKGROUND AND AIMS

Elevated fibrinogen levels have been observed in patients with acute ischemic stroke, but the association of fibrinogen with stroke outcomes is still undefined. We aimed to assess the association between baseline or 90-day fibrinogen levels and long-term outcomes in patients with ischemic stroke or transient ischemic attack (TIA).

METHODS

Using data from the China National Stroke Registry Ⅲ, this substudy included 10 518 patients within 7 days (baseline) of onset and 6268 patients at 90 days of recovery. Multivariate Cox regression and logistic regression analyses were used to assess the associations of fibrinogen with poor functional outcome (modified Rankin Scale score 3-6), dependence (modified Rankin Scale score 3-5), all-cause death, and stroke recurrence at 1 year.

RESULTS

Fibrinogen levels at 90 days were higher than those at baseline (443.5 mg/dl versus 393.7 mg/dl; p < 0.001). A high baseline fibrinogen level was associated with poor functional outcome (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.35-1.97) and dependence (OR, 1.68; 95% CI, 1.36-2.09) after adjusting for all confounding risk factors. In contrast, further adjustment for high-sensitivity C-reactive protein attenuated the association between baseline fibrinogen level and all-cause death or stroke recurrence. Furthermore, a high 90-day fibrinogen level was also associated with poor functional outcome (OR, 1.46; 95% CI, 1.07-2.00) and dependence (OR, 1.43; 95% CI, 1.03-1.98) after adjusting for all confounding risk factors.

CONCLUSIONS

High baseline and 90-day fibrinogen levels were associated with outcomes in patients with ischemic stroke or TIA.

Alcohol use and dysglycemia among people living with human immunodeficiency virus (HIV) in the Alcohol & Metabolic Comorbidities in PLWH: Evidence Driven Interventions (ALIVE-Ex) study

BACKGROUND

At-risk alcohol use is a common and costly form of substance misuse that is highly prevalent among people living with HIV (PLWH). The goal of the current analysis was to test the hypothesis that PLWH with at-risk alcohol use are more likely to meet the clinical criteria for prediabetes/diabetes than PLWH with low-risk alcohol use.

METHODS

A cross-sectional analysis was performed on measures of alcohol and glycemic control in adult PLWH (n = 105) enrolled in a prospective, interventional study (the ALIVE-Ex Study (NCT03299205)) that investigated the effects of aerobic exercise on metabolic dysregulation in PLWH with at-risk alcohol use. The Alcohol Use Disorders Identification Test (AUDIT), Timeline Followback, and phosphatidylethanol (PEth) level were used to measure alcohol use. Participants were stratified into low-risk (AUDIT score < 5) and at-risk alcohol use (AUDIT  score ≥ 5). All participants underwent an oral glucose tolerance test and measures of glycemic control- the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and Matsuda Index - were correlated with alcohol measures and compared by AUDIT score group using mixed-effects linear and logistic regression models, adjusting for age, sex, race, body mass index (BMI), and viral load.

RESULTS

In response to the glucose challenge, participants with at-risk alcohol use (n = 46) had higher glucose levels and were five times more likely to meet criteria for prediabetes/diabetes (OR: 5.3 (1.8, 15.9)) than participants with an AUDIT score < 5. Two-hour glucose values were positively associated with AUDIT score and PEth level and a higher percentage of PLWH with at-risk alcohol use had glucose values ≥140 mg/dl than those with low-risk alcohol use (34.8% vs. 10.2%, respectively).

CONCLUSION

In this cohort of PLWH, at-risk alcohol use increased the likelihood of meeting the clinical criteria for prediabetes/diabetes (2-h glucose level ≥140 mg/dl). Established determinants of metabolic dysfunction (e.g., BMI, waist-hip ratio) were not associated with greater alcohol use and dysglycemia, suggesting that other mechanisms may contribute to the impaired glycemic control observed in this cohort.

Association Between Insulin Resistance and Remote Diffusion-Weighted Imaging Lesions in Primary Intracerebral Hemorrhage

Background

Abnormal glucose metabolism was shown to be associated with the occurrence of remote diffusion-weighted imaging lesions (R-DWILs) after primary intracerebral hemorrhage (ICH) onset. Insulin resistance is a metabolic disorder that was regarded as an indicator of chronic systemic inflammation. In this study, we aimed to determine the effect of insulin resistance on the occurrence of R-DWILs in ICH.

Methods

Patients with primary ICH within 14 days after onset were prospectively enrolled from November 2017 to October 2019. R-DWILs was defined as remote focal hyperintensity from the hematoma in DWI, with corresponding hypointensity in apparent diffusion coefficient. The homeostasis model assessment of insulin resistance (HOMA-IR) was used for insulin resistance estimation and calculated as fasting insulin (μU/ml) × fasting glucose (mmol/L)/22.5. Patients in our cohort were divided into four groups according to HOMA-IR index quartiles. Logistic regression analysis and smoothing plots were used to evaluate the association of HOMA-IR with R-DWIL occurrence. Sensitivity analysis was performed in non-diabetic patients, non-obese patients, hypertensive ICH patients, and patients 60 years and older separately. The association between HOMA-IR and systemic inflammatory immune indices neutrophil to lymphocyte ratio (NLR) and monocyte to lymphocyte ratio (MLR) was examined with multiple linear regression analysis.

Results

Among the 345 patients, 54 (15.7%) had R-DWILs. Both the third and fourth quartiles of HOMA-IR index were robustly associated with an increased risk of R-DWIL occurrence (adjusted OR 3.58, 95% CI 1.33-9.65; adjusted OR 3.91, 95%CI 1.47-10.41) when compared with the first quartile. The association was consistent in non-diabetic, non-obese, hypertensive ICH patients, as well as in patients 60 years and older. Furthermore, both NLR and MLR were independently associated with HOMA-IR.

Conclusions

Our study suggested that insulin resistance evaluated with HOMA-IR index was independently associated with the presence of R-DWILs in patients with acute and subacute primary ICH. It may provide new insights into the metabolism-related brain injury after ICH ictus.

High Triglyceride Glucose Index Is Associated with Poor Outcomes in Ischemic Stroke Patients after Reperfusion Therapy

INTRODUCTION

The triglyceride glucose index (TyG index) is a simple and reliable surrogate marker of insulin resistance (IR) that can predict functional outcomes and mortality after acute ischemic stroke (AIS). However, it is unclear whether the TyG index is associated with functional outcomes in patients with stroke who receive reperfusion therapy. Thus, we aimed to explore the prognostic value of the TyG index for the clinical outcomes of patients with AIS who underwent reperfusion therapy.

METHODS

We retrospectively assessed patients with AIS, with occlusion of either the middle cerebral artery or internal carotid artery, who were evaluated using multiphase computed tomography angiography (mCTA) and received reperfusion therapy. The TyG index was calculated as "ln [fasting glucose level (mg/dL) × triglyceride level (mg/dL)]/2." Collateral status was evaluated using mCTA based on the University of Calgary Scale. Clinical outcomes included 3-month functional outcomes, early neurological deterioration, recanalization status, and hemorrhagic transformation.

RESULTS

In all, 183 subjects (age 69.5 ± 12.4 years; men, 59.0%) were enrolled. The median initial National Institutes of Health Stroke Scale score was 15.0 (interquartile range [IQR] 11-18). The median TyG index was 4.8 (IQR, 4.6-5.1), and 158 patients had TyG levels >4.49, which represents the presence of IR. On univariate analysis, a higher TyG index was associated with both early neurological deterioration (18.4 vs. 0.0%, p = 0.041) and a 3-month poor functional outcome (mRS3-6) (61.4 vs. 32.0%, p = 0.011). After adjusting for multiple variables, including age, sex, type of reperfusion therapy, recanalization status, initial stroke severity, type of stroke, and history of hypertension and diabetes, high TyG index remained an independent predictor of a poor 3-month functional outcome (adjusted OR, 5.22; p = 0.014). However, TyG levels were not significantly associated with collateral status (p = 0.756).

CONCLUSIONS

IR, represented by a high TyG index, may predict poor 3-month functional outcomes in patients with AIS who undergo reperfusion therapy.

β-Cell Function and Clinical Outcome in Nondiabetic Patients With Acute Ischemic Stroke

[Figure: see text].

Normalisation of glucose metabolism by exendin-4 in the chronic phase after stroke promotes functional recovery in male diabetic mice

BACKGROUND AND PURPOSE

Glucagon-like peptide-1 (GLP-1) receptor activation decreases stroke risk in people with Type 2 diabetes (T2D), while animal studies have shown the efficacy of this strategy to counteract stroke-induced acute brain damage. However, whether GLP-1 receptor activation also improves recovery in the chronic phase after stroke is unknown. We investigated whether post-acute, chronic administration of the GLP-1 receptor agonist, exendin-4, improves post-stroke recovery and examined possible underlying mechanisms in T2D and non-T2D mice.

EXPERIMENTAL APPROACH

We induced stroke via transient middle cerebral artery occlusion (tMCAO) in T2D/obese mice (8 months of high-fat diet) and age-matched controls. Exendin-4 was administered for 8 weeks from Day 3 post-tMCAO. We assessed functional recovery by weekly upper-limb grip strength tests. Insulin sensitivity and glycaemia were evaluated at 4 and 8 weeks post-tMCAO. Neuronal survival, stroke-induced neurogenesis, neuroinflammation, atrophy of GABAergic parvalbumin+ interneurons, post-stroke vascular remodelling and fibrotic scar formation were investigated by immunohistochemistry.

KEY RESULTS

Exendin-4 normalised T2D-induced impairment of forepaw grip strength recovery in correlation with normalised glycaemia and insulin sensitivity. Moreover, exendin-4 counteracted T2D-induced atrophy of parvalbumin+ interneurons and decreased microglia activation. Finally, exendin-4 normalised density and pericyte coverage of micro-vessels and restored fibrotic scar formation in T2D mice. In non-T2D mice, the exendin-4-mediated recovery was minor.

CONCLUSION AND IMPLICATIONS

Chronic GLP-1 receptor activation mediates post-stroke functional recovery in T2D mice by normalising glucose metabolism and improving neuroplasticity and vascular remodelling in the recovery phase. The results warrant clinical trial of GLP-1 receptor agonists for rehabilitation after stroke in T2D.

An Analysis of the Potential Relationship of Triglyceride Glucose and Body Mass Index With Stroke Prognosis

Background: The inverse association between obesity and outcome in stroke patients (known as the obesity paradox) has been widely reported, yet mechanistic details explaining the paradox are limited. The triglyceride glucose (TYG) index has been proposed as a marker of insulin resistance. We sought to explore possible associations of the TYG index, body mass index (BMI), and stroke outcome. Methods: We identified 12,964 ischemic stroke patients without a history of diabetes mellitus from the China National Stroke Registry and classified patients as either low/normal weight, defined as a BMI <25 kg/m2, or overweight/obese, defined as a BMI ≥ 25 kg/m2. We calculated TYG index and based on which the patients were divided into four groups. A Cox or logistic regression model was used to evaluate the association between BMI and TYG index and its influence on stroke outcomes, including stroke recurrence all-cause mortality and poor outcome (modified Rankin Scale score of 3-6) at 12 months. Results: Among the patients, 63.3% were male, and 36.7% were female, and the mean age of the patient cohort was 64.8 years old. The median TYG index was 8.62 (interquartile range, 8.25-9.05). After adjusting for multiple potential covariates, the all-cause mortality of overweight/obese patients was significantly lower than that of the low/normal weight patients (6.17 vs. 9.32%; adjusted hazard ratio, 0.847; 95% CI 0.732-0.981). The difference in mortality in overweight/obese and low/normal weight patients with ischemic stroke was not associated with TYG index, and no association between BMI and TYG index was found. Conclusion: Overweight/obese patients with ischemic stroke have better survival than patients with low/normal weight. The association of BMI and stroke outcome is not changed by TYG index.

Association between insulin resistance and post-ischaemic stroke outcome in patients without diabetes: protocol for a systematic review and meta-analysis

INTRODUCTION

Insulin resistance is an independent risk factor for atherosclerosis, coronary artery disease and ischaemic stroke. Currently, insulin resistance is not usually included in post-stroke risk stratification. This systematic review and meta-analysis intends to determine if available scientific knowledge supports an association between insulin resistance and post-stroke outcomes in patients without diabetes.

METHODS AND ANALYSIS

The authors will conduct a literature search in Medline, Embase, Web of Science and Cochrane Central. The review will include studies that assess the association between elevated insulin homeostasis model of insulin resistance (HOMA-IR) and post-stroke outcome (functional outcome and recurrent stroke). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines will be used. The primary outcome will be post-stroke functional outcome (Modified Rankin Scale), and the secondary outcome will be recurrent ischaemic stroke. Comparison of outcome will be made between highest and lowest HOMA-IR range (as defined in each article included in this systematic review). Risk of bias will be assessed qualitatively. Meta-analysis will be performed if sufficient homogeneity exists between studies. Heterogeneity of outcomes will be assessed by I².

ETHICS AND DISSEMINATION

No human or animal subjects or samples were/will be used. The results will be published in a peer-reviewed journal, and will be disseminated at local and international neurology conferences.

PROSPERO REGISTRATION NUMBER

CRD42020173608.

Modulation of insulin resistance by renin angiotensin system inhibitors: implications for cardiovascular prevention

Insulin resistance (IR) and the related hyperinsulinamia play a key role in the genesis and progression of the continuum of cardiovascular (CV) disease. Thus, it is reasonable to pursue in primary and secondary CV prevention, the pharmacological strategies that are capable to interfere with the development of IR. The renin-angiotensin-aldosterone system (RAAS) plays an important role in the pathogenesis of IR. In particular, angiotensin II (Ang II) through the generation of reactive oxygen species, induces a low grade of inflammation, which impairs the insulin signal transduction. The angiotensin converting enzyme (ACE) inhibitors are effective not only as blood pressure-lowering agents, but also as modulators of metabolic abnormalities. Indeed, experimental evidence indicates that in animal models of IR, ACE inhibitors are capable to ameliorate the insulin sensitivity. The Ang II receptor blockers (ARBs) modulate the peroxisome proliferator-activated receptor (PPAR)-γ activity. PPARâ€"γ is a transcription factor that controls the gene expression of several key enzymes of glucose metabolism. A further mechanism that accounts for the favorable metabolic properties of ARBs is the capability to modulate the hypothalamicâ€"pituitary-adrenal (HPA) axis. The available clinical evidence is consistent with the concept that both ACE inhibitors and ARBs are able to interfere with the development of IR and its consequences like type 2 diabetes. In addition, pharmacological inhibition of the RAAS has favourable effects on dyslipidaemias, metabolic syndrome and obesity. Therefore, the pharmacological antagonism of the RAAS, nowadays, represents the first choice in the prevention of cardio-metabolic diseases.

Concurrency of Early-Age Exposure to Chinese Famine and Diabetes Increases Recurrence of Ischemic Stroke

Background and Purpose: Early age exposure to the Chinese Great Leap Forward famine (1959–1961) is associated with the incidence of risk factors for ischemic stroke. This study aims to examine the relationship between early age famine exposure and 12-month stroke recurrence. We sought to explore the interaction between famine exposure status and metabolic phenotypes on stroke recurrence and how the adherence of crucial evidence-based key performance indicators (KPI) would modify this interaction.

Methods: We analyzed data of patients who were born between 1953 and 1964 in the China National Stroke Registry II (CNSR-II). The study population was further divided into five subgroups for comparing 12-month stroke recurrence. A multivariate Cox proportional hazard regression model was used in analyzing the impact of the concurrence of metabolic phenotypes—type 2 diabetes (T2D) or metabolic syndrome (MetS)—and early-age famine exposure on recurrent risk. The influence of the adherence to predefined KPI and concurrency of metabolic phenotype was also evaluated.

Results: Concurrent T2D and early age famine exposure was associated with an increased recurrence risk of ischemic stroke with 12 months [adjusted hazard ratio (HR): 1.63, 95% confidence interval (CI) 1.28–2.07]. Optimal adherence to KPI was not associated with significantly reduced risk of 12-month stroke recurrence (adjusted HR: 0.80, 95% CI: 0.51–1.26).

Conclusions: Concurrency of early-age famine exposure and diabetes mellitus was associated with a higher risk of stroke recurrence within 12 months, and adherence to evidence-based KPI did not reduce the risk significantly.

Association between insulin resistance and aspirin or clopidogrel resistance in Chinese patients with recent ischemic stroke/TIA

Objective: This study aims to discover whether insulin resistance is an independent predictor for antiplatelet drug resistance in patients with ischemic cerebrovascular disease.Methods: This study used a prospective cohort method. Patients diagnosed as minor ischemic stroke or transient ischemic attack (TIA) were enrolled successively. All patients have been administrated aspirin and/or clopidogrel and were tested for fasting glucose and insulin and platelet aggregation inhibition tests which was detected by light transmission aggregometry (LTA). The maximum platelet aggregation rate (AA) of ≥20% or the maximum platelet aggregation rate (ADP) of ≥50% was defined as antiplatelet drug resistance. Multivariable logistic regression was performed to estimate the association between HOMA-IR and antiplatelet drug resistance.Results: This study recruited successively 237 patients with mild-to-moderate ischemic stroke or TIA in Beijing Tiantan Hospital from 2018 to 2019. Of them 60 cases were recognized as having insulin resistance. There are 46 patients in insulin resistance group (76.7%) developed antiplatelet drug resistance, which was significantly more frequent than patients without insulin resistance (35%, P < 0.0001). Insulin resistance was an independent risk factor for antiplatelet drug resistance in patients with recent ischemic stroke/TIA after adjusted for confounding factors (Odds Ratio 5.281; 95%CI, 2.15 to 13.01, P < 0.0001).Conclusions: Insulin resistance was an independent predictor for development of antiplatelet drug resistance in patients with recent minor ischemic stroke or TIA. More attention should be paid to recognize these patients and antithrombotic effect should be monitored when antiplatelet drugs were applied to these patients.

Insulin resistance is associated with poor functional outcome after acute ischemic stroke in non-diabetic patients

Insulin resistance is associated with the occurrence of stroke and atherosclerotic disease. However, the relationship between insulin resistance and the prognosis of acute ischemic stroke in non-diabetic patients is unclear. We hypothesized that insulin resistance might affect short-term functional recovery after acute ischemic stroke in non-diabetic patients. Between May 2014 and December 2016, 1377 consecutive patients with acute ischemic stroke were enrolled from a prospectively maintained stroke registry. After excluding patients with transient ischemic attacks (TIA), pre-stroke disabilities, diabetes mellitus, and patients with incomplete evaluations, 517 patients were included in the study. The homeostasis model assessment of insulin resistance (HOMA-IR) score was used to evaluate the degree of insulin resistance. The patients with the highest quartile of log HOMA-IR index scores were younger and had higher fasting blood glucose, total cholesterol, triglycerides, low-density lipoprotein, and HbA1c levels. Multivariable logistic regression analysis revealed that log HOMA-IR scores were independently associated with poor prognosis after adjusting for age and sex and p < 0.1 in univariable analysis. Insulin resistance was associated with the poor functional outcome of non-diabetic stroke patients. This evidence supports treating insulin resistance in acute ischemic stroke patients with blood glucose levels within the normal range.

Insulin Resistance is Significantly Related with Worse Clinical Outcomes in Non-Diabetic Acute Ischemic Stroke Patients Treated with Intravenous Thrombolysis

OBJECTIVES

to investigate the relationship between insulin resistance (IR) and clinical outcomes in non-diabetic ischemic stroke patients treated with intravenous thrombolysis.

METHODS

We recruited non-diabetic ischemic stroke patients treated with intravenous thrombolysis prospectively. IR was defined as homeostasis model assessment-estimated insulin resistance index ≥2.80. Initial stroke severity was assessed using the National Institutes of Health Stroke Scale scores, and infarct volume was measured using DWI. Clinical outcomes were evaluated by neurological improvement and hemorrhagic transformation at 24 hours, and favorable functional prognosis at 90 days.

RESULTS

232 patients were enrolled into this study. IR group was 67 patients, non-IR group was 165 patients. Compared with the non-IR group, the probability of neurological improvement at 24 h ours and favorable functional outcome at 90 days in IR group were all significantly lower (41.79% vs 63.03%, p<0.01; 73.13% vs 89.09%, p<0.01 respectively), whereas the ratio of hemorrhagic transformation was much higher (16.42% vs 4.85%, p<0.01). In multivariable logistic regression, IR was negatively associated with neurological improvement and favorable functional prognosis (OR=0.39, 95%CI, 0.20-0.76, p<0.01; OR= 0.26, 95%CI, 0.07-0.91, p=0.04, respectively), but was positively correlated with hemorrhagic transformation (OR=4.07, 95%CI, 1.13-14.59, p=0.03) after adjusting traditional risk factors. We analyzed 108 infarct volume data further, the median of volume in IR group was 2.27 cm³, higher than that in non-IR group (1.96 cm³), but no statistical difference (p=0.65).

CONCLUSIONS

In non-diabetic ischemic stroke patients treated with intravenous thrombolysis, IR was related with worse clinical outcomes, but not with infarct volume.

Effect of prediabetes on asprin or clopidogrel resistance in patients with recent ischemic stroke/TIA

OBJECTIVE

Diabetes mellitus (DM) had been discovered as an independent risk factor for high on-treatment platelet reactivity (HPR) in patients with ischemic stroke. However, studies on the relationship between prediabetes and the occurrence of HPR remain scarce. This study is aimed at clarifying the association between prediabetes and HPR among patients with recent ischemic stroke or transient ischemic stroke (TIA).

METHODS

Patients with ischemic stroke or TIA within 90 days after onset were recruited consecutively. All patients were divided into three groups: DM, prediabetes, and normal glucose tolerance according to fasting glucose, HbA1c, or OGTT. Three months later, all patients were performed platelet aggregation inhibition test and screened for high on-treatment platelet reactivity. The effect of prediabetes on HPR was analyzed in a multivariable logistic regression model.

RESULTS

This study recruited 237 patients with ischemic stroke or TIA, including 57 cases with prediabetes, 108 with DM, and 72 with normal glucose tolerance. Aspirin and/or clopidogrel resistance was discovered in 28 cases among prediabetes group, which was significantly more frequent than normal glucose tolerance group(49.1% versus 33.3%, P = 0.046). After adjusting for confounding factors, prediabetes was found as an independent risk factor for high on-treatment platelet reactivity (HPR) among patients with recent ischemic stroke or TIA (odds ratio 2.92; 95% CI, 1.29 to 6.63, P = 0.01).

CONCLUSIONS

Prediabetes was an independent risk factor for high on-treatment platelet reactivity in patients with recent ischemic cerebrovascular disease. Patients with prediabetes should be highlighted for the efficacy test of antiplatelet drugs.

Prevalence of Insulin Resistance in Adults Living with HIV: Implications of Alcohol Use

Unhealthy alcohol use is prevalent among persons living with HIV (PLWH). Aging and increased survival of PLWH on antiretroviral therapy (ART) are complicated by metabolic dysregulation and increased risk of insulin resistance (IR) and diabetes mellitus. The objective of this study was to determine the prevalence and association of IR with unhealthy alcohol use in adult in-care PLWH. A cross-sectional analysis of metabolic parameters and alcohol use characteristics was conducted in adult PLWH enrolled in the New Orleans Alcohol Use in HIV (NOAH) Study. IR was estimated using homeostatic model assessment (HOMA-IR), triglyceride index, and McAuley index and beta cell function (HOMA-β). Alcohol use was assessed using Alcohol Use Disorders Identification Test (AUDIT)-C, 30-day timeline followback (TLFB), lifetime drinking history, and phosphatidylethanol (PEth) measures. A total of 351 participants, with a mean age [±standard deviation (SD)] of 48.1 ± 10.4 years, were included (69.6% male). Of these, 57% had an AUDIT-C score of 4 or greater, indicating unhealthy alcohol use. Mean body mass index (BMI) was 27.2 ± 7.0 kg/m², 36.4% met criteria for metabolic syndrome, and 14% were diagnosed with diabetes. After adjusting for education, race, BMI, smoking status, viral load, CD4 count, use of protease inhibitors, statins, or metformin; physical activity and diabetes diagnosis, HOMA-IR, and McAuley index were negatively associated with AUDIT-C, and HOMA-β cell function was negatively associated with AUDIT-C, PEth, and TLFB. Cross-sectional analysis of NOAH participants indicates that alcohol use is associated with decreased HOMA-β cell function, suggesting dysregulation of endocrine pancreatic function.

Triglyceride Glucose Index and Prognosis of Patients With Ischemic Stroke

Background: The triglyceride glucose index (TyG index) has been proposed as a simple and credible surrogate marker of insulin resistance. However, it is unclear whether TyG index correlates with adverse clinical outcomes in patients with ischemic stroke. Accordingly, this study aimed to explore the relationship between baseline TyG index and clinical outcomes of ischemic stroke individuals. Methods: We included eligible subjects with ischemic stroke from the China National Stroke Registry II for the current analysis. TyG index was calculated and divided into quartiles to explore the relationship with the outcomes of ischemic stroke. Outcomes included stroke recurrence, all-cause mortality, poor functional outcome at 12 months, and neurologic worsening at discharge. Multivariable Cox regression and logistic regression models were performed to explore the correlation of baseline TyG index with the outcomes. Results: Among the 16,310 patients enrolled in the study, the average age was 64.83 ± 11.9 years, and 63.48% were men. The median TyG index was 8.73 (interquartile range, 8.33-9.21). After adjustment for multiple potential covariates, the fourth quartile of TyG index was associated with an increased risk of stroke recurrence (adjusted HR, 1.32; 95% CI, 1.11-1.57; P = 0.002), all-cause mortality (adjusted HR, 1.25; 95%CI, 1.06-1.47; P = 0.01) at 12-month follow-up, and neurological worsening (adjusted OR, 1.26; 95% CI, 1.02-1.55; P = 0.03) at discharge, but not poor functional outcome compared with the first quartile. Conclusion: TyG index representing insulin resistance was associated with an increased risk of stroke recurrence, all-cause mortality, and neurologic worsening in patients with ischemic stroke.

Pioglitazone and PPAR-γ modulating treatment in hypertensive and type 2 diabetic patients after ischemic stroke: a national cohort study

Background and aim

Peroxisome proliferator-activated receptor-γ (PPAR-γ) modulating treatment may have cardiovascular benefits in type 2 diabetes mellitus (T2DM) patients after ischemic stroke (IS). However, whether there are additional benefits from intensive PPAR-γ modulating treatments in Asian patients with T2DM and hypertension (HTN) after IS remains unknown.

Methods

Between 2001 and 2013, patients admitted due to IS were identified from the National Health Insurance Research Database of Taiwan. Patients with T2DM and HTN using angiotensin receptor blockers were further included. Eligible patients were divided into two groups: (1) pioglitazone and (2) non-pioglitazone oral anti-diabetic agent groups. Propensity score matching (1:2) was used to balance the distribution of baseline characteristics, stroke severity and medications. The primary outcome was recurrent IS. Subgroup analysis for recurrent IS in pioglitazone and/or telmisartan users, the trend of IS risks across different PPAR-γ intensity treatments, and dose-dependent outcomes across different pioglitazone possession ratios were further studied. Statistical significance was set at p < 0.05 and p < 0.1 for clinical outcomes and interaction of subgroup analyses, respectively.

Results

There were 3190 and 32,645 patients in the pioglitazone and non-pioglitazone groups. Patients of the pioglitazone group had a lower risk of recurrent IS (subdistribution hazard ratio, 0.91; 95% confidence interval 0.84–0.99). Pioglitazone was also associated with reduced recurrent IS in patients who also used telmisartan (p for interaction = 0.071). A graded correlation was found a borderline significant trend between the intensity of PPAR-γ therapy and following IS (p = 0.076). The dose-dependent outcome also showed that a borderline significant trend that higher pioglitazone possession ratio was associated with a lower risk of recurrent IS (p = 0.068).

Conclusions

The current study suggests that the use of pioglitazone in type 2 diabetic and hypertensive IS patients is associated with fewer recurrent IS events in an Asian population. Concurrent telmisartan use or a higher pioglitazone possession ratio may have a trend of increased pleiotropic effects, which could possibly be related to higher PPAR-γ effects. Future studies are warranted to confirm or refute the clinical effects and the possible mechanism of more intensive PPAR-γ-modulating treatments.

Insulin Resistance Is Independently Associated With Enlarged Perivascular Space in the Basal Ganglia in Nondiabetic Healthy Elderly Population

OBJECTIVES

To investigate the association between insulin resistance (IR) and enlarged perivascular space (EPVS) in the basal gangliain nondiabetic healthy elderly population.

METHODS

A total of 235 nondiabetic healthy elderly population were recruited. A 3-level scale was used to evaluate the burden of EPVSs. The homeostasis model assessment-estimated insulin resistance index (HOMA-IR) was used for IR estimation. Correlation between IR and severity of EPVS was assessed using the regression model after adjusting demographics and cardiovascular risk factors.

RESULTS

The top quartile of HOMA-IR was 2.52, and 25.11% of patients showed IR. The proportion of patients with IR was higher in the moderate to severe EPVS group than in the mild group (36.51% vs 20.93%, P = .015). In multivariate logistic analysis, IR was positively correlated with the moderate to severe EPVS (adjusted odds ratio: 3.532, 95% confidence interval: 1.633-7.636, P = .001) after adjusting classical risk factors.

CONCLUSIONS

Insulin resistance was independently correlated with EPVS in the basal ganglia in nondiabetic healthy elderly population.

Stress Hyperglycemia and Outcome of Non-diabetic Patients After Acute Ischemic Stroke

Background and Purpose: Stress hyperglycemia is relative hyperglycemia after suffering an acute illness such as stroke, even without preexisting diabetes. Our study aimed to determine the relationship between stress hyperglycemia and outcome of non-diabetic patients with acute ischemic stroke.

Methods: Data were derived from the ACROSS-China (Abnormal Glucose Regulation in Patients with Acute Stroke across China) registry. Patients with ischemic stroke but without a history of diabetes mellitus were included in this analysis. Stress hyperglycemia was measured by glucose-to-glycated hemoglobin (HbA1c) ratio which was calculated by fasting plasma glucose (FPG) divided by HbA1c. We investigated the association between quartiles of glucose-to-HbA1c ratio and stroke recurrence and all-cause death at 12 months after stroke onset.

Results: We included a total of 999 patients, among which there were 105 (10.9%) recurrent strokes and 76 (7.6%) deaths at 12 months. Using the lowest quartile of glucose-to-HbA1c ratio as the reference, patients with the highest quartile were associated with an increased risk of stroke recurrence [16.0 vs. 8.3%; adj.hazards ratio (HR) = 2.19, 95% confidence interval (CI): 1.26–3.83] and death (13.0 vs. 4.3%; adj.HR=2.86, 95%CI: 1.38–5.90) at 12 months after adjusted for potential covariates. We also observed that a higher level of glucose-to-HbA1c ratio was associated with an elevated risk of stroke recurrence and death.

Conclusion: Stress hyperglycemia, measured by glucose-to-HbA1c ratio, was related to an elevated risk of stroke recurrence and all-cause death in patients with acute ischemic stroke but without diabetes.

Homeostasis model assessment of insulin resistance and outcome of ischemic stroke in non-diabetic patients - a prospective observational study

Background

Insulin resistance (IR) in relation to diabetes is a risk factor for ischemic stroke (IS), whereas less is known about non-diabetic IR and outcome after IS.

Methods

In non-diabetic IS (n = 441) and controls (n = 560) from the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS), IR was investigated in relation to IS severity and functional outcome. IR was evaluated acutely and after 3 months using the Homeostasis model assessment of IR (HOMA-IR). Stroke severity was assessed by the National Institutes of Health Stroke Scale (NIHSS). Functional outcome was evaluated using the modified Rankin Scale (mRS) after 3 months, 2 and 7 years. Associations were evaluated by logistic regression.

Results

Higher acute and 3-month HOMA-IR was observed in IS compared to the controls (both p < 0.001) and in severe compared to mild IS (both p < 0.05). High acute HOMA-IR was associated with poor outcome (mRS 3–6) after 3 months and 7 years [crude Odds ratios (ORs), 95% confidence intervals (CIs) 1.50, 1.07–2.11 and 1.59, 1.11–2.30, respectively], but not after 2 years. These associations lost significance after adjustment for all covariates including initial stroke severity. In the largest IS subtype (cryptogenic stroke), acute HOMA-IR was associated with poor outcome after 2 years also after adjustment for age and stroke severity (OR 2.86, 95% CI 1.01–8.12).

Conclusions

In non-diabetic IS patients, HOMA-IR was elevated and related to stroke severity, but after adjustment for IS severity, the associations between HOMR-IR and poor outcome lost significance. This could suggest that elevated IR mostly is a part of the acute IS morbidity. However, in the subgroup of cryptogenic stroke, the associations with poor outcome withstood correction for stroke severity.

Insulin Resistance Is a Risk Factor for Overall Cerebral Small Vessel Disease Burden in Old Nondiabetic Healthy Adult Population

Background and Purpose: This study aimed to investigate the association between insulin resistance (IR) and the overall cerebral small vessel disease (CSVD) burden.

Methods: We recruited elderly, nondiabetic, healthy subjects prospectively. The overall effect of CSVD on the brain was described by a validated CSVD score. The homeostasis model assessment–estimated insulin resistance index (HOMA-IR) was used for IR estimation, and HOMA-IR ≥2.80 was defined as IR. We evaluated the association between IR and the increasing severity of CSVD score by ordinal regression models adjusting for demographics and cardiovascular risk factors.

Results: A total of 156 healthy participants were recruited. The mean age was older in the IR group than in the non-IR group (70.03 vs. 67.45, p = 0.04), and the prevalence of hypertension was significantly higher in the IR group than in the non-IR group (82.35% vs. 53.28%, p < 0.01). In ordinal regression analysis, IR was positively associated with increasing severity of the total CSVD score (adjusted odds ratio, 3.74; 95% confidence interval, 1.63–5.08; p < 0.01) after adjusting traditional risk factors. Furthermore, HOMA-IR levels showed a positive dose-dependent correlation with the total CSVD score (p < 0.01, p for trend <0.01).

Conclusions: IR is independently associated with increasing severity of the overall CSVD burden, independent of other clinical risk factors in an elderly, nondiabetic, healthy population. Furthermore, HOMA-IR level is correlated with the CSVD burden in a dose-dependent manner.

Obesity-Stroke Paradox Exists in Insulin-Resistant Patients But Not Insulin Sensitive Patients

Background and Purpose- The underlying mechanisms of stroke-obesity paradox are still not fully understood. This study aims to investigate the contribution of insulin resistance to the association between body mass index and stroke outcomes. Methods- Patients with ischemic stroke without history of diabetes mellitus in the Abnormal Glucose Regulation in Patients With Acute Stroke Across-China registry were included. Overweight or obese was defined as body mass index ≥23, and the median of homeostasis model assessment-insulin resistance index was chosen as cutoff to define insulin resistance. Cox or logistic regression model was used to assess the interaction between body mass index and homeostasis model assessment-insulin resistance on 1-year prognosis (all-cause mortality and poor functional outcome defined as modified Rankin Scale score 3-6). Results- Of 1227 study participants, the median homeostasis model assessment-insulin resistance was 1.9 (interquartile range, 1.1-3.1) and 863 (70.3%) patients were classified as overweight or obese. Among insulin-resistant patients, overweight/obese patients experienced one-half of the risk of death after stroke than their low/normal weight counterparts (9.42% versus 17.69%, unadjusted hazard ratio, 0.50; 95% CI, 0.31-0.82), while among insulin-sensitive ones, no significant difference of mortality risk was found (7.58% versus 6.91%, 1.07; 0.57-1.99). Similar trends were observed for poor functional outcome. Results were similar after adjustments for confounders. There were significant interactions between body mass index and homeostasis model assessment-insulin resistance on the risks of mortality (P=0.045) and poor functional outcome (P=0.049). Conclusions- We observed the obesity paradox for mortality and functional outcome in insulin-resistant patients but did not find the obesity paradox in insulin-sensitive patients. Insulin resistance may be one of the mechanisms underlying the obesity paradox of the outcome in patients with ischemic stroke.

Association between HOMA-IR and Frailty among U.S. Middle-aged and Elderly Population

Previous literatures revealed that homeostasis model assessment-estimated insulin resistance (HOMA-IR) was one of the cardio-metabolic risk factors. This study was conducted to access the association between HOMA-IR and frailty in the United States of America (U.S.) middle-aged and elderly high-risk insulin-resistant population. In the National Health and Nutrition Examination Survey (NHANES III) from 1988 to 1994, the study included 3,893 participants. In order to exam the association between HOMA-IR and frailty in the middle-aged and elderly population through the regression model adjusted for multiple covariates, we divided the participants into middle aged group (Age <65 years) and elderly group (Age > = 65 years) in this study. Each group was then divided into tertiles depending on their HOMA-IR levels. Higher level of HOMA-IR was significantly associated with frailty in the elderly group, but this association was not seen in the middle-aged population. These results demonstrated that the HOMA-IR level can be a novel risk assessment of frailty in elderly high-risk insulin-resistant individuals (Age > = 65 years).