Cholesterol and the Risk of Ischemic Stroke

Abstract

Background and Purpose-Large epidemiological studies have not established cholesterol levels as a risk factor for ischemic stroke, but recent clinical trials have demonstrated a reduction in the ischemic stroke rate for patients taking HMG-CoA reductase inhibitors ("statins"). The goal of this study was to evaluate whether total cholesterol (TC), high-density lipoprotein (HDL), triglycerides, and the TC:HDL ratio are risk factors for ischemic stroke in apparently healthy men enrolled in the Physicians' Health Study. Methods-We used a nested case-control study design and matched 296 ischemic stroke cases with an equal number of controls on age, tobacco use, and follow-up time. At baseline, TC, HDL, and triglyceride levels were measured. We calculated odds ratios (ORs) and their 95% confidence intervals (CIs) using conditional logistic regression, adjusting for major risk factors for ischemic stroke. Results-Compared with the reference lowest quartile, the highest quartile for TC had an adjusted OR of 1.56 (95% CI, 0.84 to 2.92), the highest quartile of HDL had an adjusted OR of 0.75 (95% CI, 0.43 to 1.30), and the highest quartile of triglycerides had an adjusted OR of 1.07 (95% CI, 0.63 to 1.82). Although the highest quartile of the TC:HDL ratio had an adjusted OR of 1.62 (95% CI, 0.93 to 2.82), the risk of ischemic stroke was not a linear relationship. Conclusions-After adjustment, TC, HDL, and triglycerides were not significantly associated with ischemic stroke risk, and for the TC:HDL ratio, a suggestion of increased risk of ischemic stroke was limited to those with the highest levels.

Transesophageal Echo Study in Patients With Acute Ischemic Stroke

“…In our study , there was no significant difference between the age groups .regarding hypertriglyceridemia (19% of group A, 28% of group B and 9% of group C) .This was in agreement with Bowman et al (40) ;They found no correlation between non fasting triglycerides and ischemic stroke was found. In another case-control study conducted by Sridharan et al (41) fasting triglyceride level were studied in 204 patients with acute ischemic stroke and 204 controls, they did not find any significant association between fasting triglycerides and acute ischemic stroke.…”

Effect of Lipid Profile Upon Prognosis in Ischemic and Haemorrhagic Cerebrovascular Stroke

“…Shahar et al [15], Bowman et al [16] reported the lack of association between lipids and stroke. Study conducted by Bowman et al, of 296 stroke patients and the same number of controls, found that levels neither of total cholesterol, triglycerides nor HDL were associated with risk of ischemic stroke, although a high total cholesterol/HDL ratio was found to increase the risk.…”

“…Studies of cholesterol levels in stroke patients have revealed results varying from insignificant changes to a moderate elevation [14]. There are several studies which have not found any association between lipid profile and incident ischemic stroke [15,16]. The aim of this study was to delineate the reliability and accuracy of serum lipid profile in assessing the prognosis/neurological worsening in patients with ischemic and hemorrhagic cerebrovascular stroke.…”

Evidence from biomarkers and surrogate endpoints

“…In stroke, measuring low-density lipoprotein (LDL) and high-density lipoprotein cholesterol or electrocardiogram changes can provide important information regarding risk. [45][46][47][48][49][50] Changes in these measures in response to therapy can reliably alter the risk. For example, converting atrial fibrillation to normal sinus rhythm will reduce the risk of stroke.…”