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.

Intravenous thrombolysis with tissue-plasminogen activator in small vessel occlusion

Intravenous tissue-plasminogen activator (IV-TPA) treatment in acute ischemic stroke (AIS) patients due to small vessel occlusion (SVO) has been debated because of its small expected benefit and symptomatic intracranial hemorrhage (SICH) risk. Furthermore, data on subgroups of SVO patients are limited. From a prospective multicenter stroke registry database, AIS patients due to SVO within 24 h from onset were selected. Efficacy outcomes were 3-month modified Rankin Scale (mRS) score 0-1 proportion and mRS score distribution. Additionally, subgroup analyses were conducted by age, sex, initial National Institute Health Stroke Scale (NIHSS) score, and presenting limb paresis. This study included 2482 patients: 193 in the IV-TPA group and 2289 in the control group. After adjusting covariates, IV-TPA treatment was associated with an increased mRS 0-1 outcome (adjusted OR [95% CI], 1.56 [1.06-2.29]; P = 0.0249), but was not significantly associated with a favorable mRS shift (1.33 [0.98-1.81]; P = 0.0709). SICH and 3-month death occurred in three (1.6%) and none in the IV-TPA group versus one (0.04%) and 16 (0.7%) in the control group. In subgroup analyses, the IV-TPA effect appeared significantly greater in patients aged ≥80 versus <80 for mRS score distribution (P_interaction = 0.012). This study showed that, in SVO patients, IV-TPA within 4.5 h may improve functional outcome with a low SICH risk. The benefit appeared more substantial in patients aged ≥80.

Two different clinical entities of small vessel occlusion in TOAST classification

BACKGROUND

Small deep infarcts might be classified into 2 types: lacunar and branchatheromatous infarcts. However, since their initial description, small deep infarcts were still regarded as the same category of the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, small vessel occlusion (SVO). We hypothesized that the 2 types of small deep infarcts would be distinct clinical entities. This study was conducted to investigate the clinical characteristics in the 2 groups of patients according to lesion pattern and combined atherosclerotic diseases.

METHODS

We included patients with small deep infarcts in the subcortical area. The patients were divided into 2 groups: (1) island lesions and (2) linear lesions on coronal diffusion weighted imaging. The status of the relevant artery was categorized as no stenosis, non-significant (<50% of luminal narrowing) and significant (≥ 50% of luminal narrowing). We compared the clinical and imaging characteristics of two lesion types according to various arterial status.

RESULTS

This study analyzed a total of 248 patients. Independent factors for island lesions on coronal DWI were male, severe leukoaraiosis, microbleeds, abnormal glycated hemoglobin (HbA1C), and abnormal estimated glomerular filtration ratio (eGFR) adjusted by age, sex, and initial National Institutes of Health Stroke Scale. In addition, in patients without significant relevant arterial stenosis, island lesion patterns were more frequently associated with severe periventricular white matter hyperintensity, diabetes mellitus, abnormal eGFR and abnormal HbA1C than linear lesion patterns.

CONCLUSION

This study demonstrated that SVO of TOAST classifications had different imaging and clinical characteristics according to the lesion patterns of coronal imaging. It suggests that two types of SVO should be regarded as the different categories of stroke classification.