The complex relationship between cholesterol and brain hemorrhage

The Prevalence of Dyslipidemia and Hyperglycemia among Stroke Patients: Preliminary Findings

Background/Aim

Stroke or cerebrovascular accident is defined as sudden or sub acute onset of focal neurologic deficit, caused by the interruption of blood flow to parts of the brain. In this study, we aimed to investigate the prevalence of dyslipidemia and hyperglycemia among stroke patients in Palestine.

Materials and Methods

A total of 70 patients with stroke were included in a cross-sectional study between November 2017 and February 2018. Stroke patients were diagnosed based on a CT scan reviewed by a neurologist. Fasting venous blood samples were collected to measure the lipid profile (cholesterol, low-density lipoproteins (LDL), triacylglycerol (TAG), high-density lipoproteins (HDL)), fasting blood glucose (FBG), and glycosylated hemoglobin (Hb_A1c) levels. An interview-based questionnaire, included background data, past medical history, family history, and other risk factors for stroke, was filled for each patient.

Results

Based on our results, 28.57% of patients had high LDL, 17.1% had high cholesterol, 15.7% had high TAG and 61.3% had low HDL. About half of the patients (51.4%) had abnormal Hb_A1c and abnormal FBG (52.8%). The majority (67.1%) of patients were males, whereas, 11% of patients were obese (BMI of more than 30 kg/m²) and 51.4% were smokers. Regarding the family history of diseases, 81% of patients had a family history of hypertension, 50% had a family history of stroke, and 58% had a family history of diabetes mellitus.

Conclusion

Male gender and smoking were most likely to increase the risk of stroke. Risk factors like low HDL, high LDL, high FBG, high Hb_A1c, and hypertension contribute substantially to the incidence of stroke. A family history of stroke, hypertension and diabetes were significant risk factors for stroke.

Minimization of Intraparenchymal Hemorrhagic Stroke Size by Optimization of Serum Lipids

Introduction

Intraparenchymal hemorrhages (IPHs) are the most common type of hemorrhagic stroke. One of the main associated risk factors is total cholesterol (TC) above 200. A severely decreased level of TC potentially interferes with the stabilization of the cell membrane and can potentially lead to a larger hemorrhage. Previous population-based studies have confirmed an association between low TCs and a high incidence of hemorrhagic stroke. It has been established that a TC below 200 decreases the potential for cardiovascular disease. This study suggests that the balance that needs to be achieved between these two extremes presents a unique possibility for an optimal therapeutic range of total cholesterol levels.

Materials & methods

Inclusion criteria included all adult patients with International Classification of Diseases (ICD)-9/10 code for hemorrhagic stroke, from June 2007 to June 2017. A total of 300 patients met the criteria (N=300). For each patient, the following data were collected: NIH Stroke Scale, TC level, triglyceride level, low-density lipoprotein (LDL) and high-density lipoprotein (HDL), cholesterol reducing medications, size of hemorrhage on computed tomography (CT) of the head, location of hemorrhage, and patient disposition. Statistical analysis was done using the Generalized Linear Modeling with Wald Chi-square as the statistical determinant.

Results

Intracerebral hemorrhage size is dependent on the intracranial location with brain lobes having larger bleeds. Minimum hemorrhage size was noted in TC 188-196 and this effect was statistically significant independent of location. HDL has a significant independent effect on hemorrhage size with overall minimum bleed occurring in the range of 43-51 mg/dL HDL (98-106 mg/dL for men and 43-51 mg/dL for women). This sex effect within HDL on hemorrhage size is statistically significant. There was a differential effect of HDL dependent on patient race. Asian and black patients had least IPH volume with HDL 70-79 mg/dL, while Hispanic patients had a minimum at 43-51 mg/dL. White patients required a higher HDL, 80-88 mg/dL to minimize the IPH size. The triglyceride level had a statistically significant independent effect on the bleed size with the minimum hemorrhage size occurring in the range of 205-224 mg/dL. This effect was nuanced by patient race with statistically significant minimum IPH size occurring at 144-164 mg/dL for white patients, 124-143 mg/dL for Hispanic and black patients, and 84-103 mg/dL for Asian patients. Post-hospital patient disposition was not significantly affected by any of the above predictor variables.

Conclusion

This study found TC, HDL and triglycerides in specific ranges are associated with significantly decreased hemorrhage size across all genders and hemorrhage locations. The ranges with the strongest hemorrhage-limiting effect are as follows: TC 188-196 mg/dL, HDL 43-51 mg/dL (98-106 mg/dL for men and 43-51 mg/dL for women), triglycerides 205-224 mg/dL. Lipids both below and above these ranges yield larger bleeds. It also found larger brain areas will have more extensive hemorrhage than smaller brain areas. Future work in this arena should include collaboration with cardiology to determine ideal ranges for both cardio- and neuroprotection as well as a prospective study to validate the applicability of these findings in patient care.

White matter hyperintensity burden and susceptibility to cerebral ischemia

BACKGROUND AND PURPOSE

White matter hyperintensity (WMH) burden increases risk of ischemic stroke; furthermore, it predicts infarct growth in acute cerebral ischemia. We hypothesized that WMH would be less severe in patients with TIA as compared to those with acute ischemic stroke and completed infarct.

METHODS

Cases (TIA, n = 30) and controls (acute ischemic stroke, n = 120) were selected from an ongoing longitudinal cohort study of patients with stroke and matched for age, gender, and race/ethnicity. All subjects had brain MRI within 48 hours of presentation to evaluate for evidence of acute cerebral ischemia. WMH burden on MRI was quantified using a validated computer-assisted program with high inter-rater reliability.

RESULTS

Median WMH volume in individuals with TIA was 3.7 cm³ (interquartile range, 1.5 - 8.33 cm³) compared to 6.9 cm³ (interquartile range, 3.1-11.9 cm³) in acute ischemic stroke (P < 0.04). In multivariable analysis, the odds of completed infarct were higher (OR, 2.19; 95% CI, 1.27-3.77; P < 0.005) in subjects with larger volumes of WMH.

CONCLUSIONS

WMH burden was significantly less in subjects with TIA as opposed to those with ischemic stroke. These data provide further evidence to support a detrimental role of WMH burden on the capacity of cerebral tissue to survive acute ischemia.