Pravastatin therapy and the risk of stroke

The value of serial plasma nuclear and mitochondrial DNA levels in acute spontaneous intra-cerebral haemorrhage

BACKGROUND

Increased plasma nuclear and mitochondrial DNA levels may be connected to disease severity following spontaneous intra-cerebral haemorrhage (ICH). This study tested the hypothesis that plasma nuclear and mitochondrial DNA levels are substantially increased in acute ICH and can predict treatment outcomes.

METHODS

Serial plasma nuclear and mitochondrial DNA levels were examined in 60 consecutive patients admitted within 24 h after onset of spontaneous ICH and in 60 volunteer control subjects. Additional samples were obtained on days 4, 7, 10, and 14 after onset of ICH regardless of clinical deterioration.

RESULTS

Only plasma nuclear DNA, not plasma mitochondrial DNA, levels in patients with spontaneous ICH significantly correlated with Glasgow Coma Scale (GCS) (r = -0.467, P = 0.001) and ICH volume (r = 0.515, P ≤ 0.001) on presentation. Plasma nuclear DNA levels increased significantly from day 1 to day 7 in patients with poor outcome. Higher plasma nuclear DNA levels (cut-off value >18.7 ng/ml) on presentation were associated with poor outcomes in spontaneous ICH patients.

CONCLUSION

Plasma nuclear DNA levels reflect the severity of cerebral damage such that higher levels are associated with poorer outcome. Plasma nuclear DNA level can be considered a neuropathologic marker of acute spontaneous ICH.

Secondary stroke prevention: patent foramen ovale, aortic plaque, and carotid stenosis

Stroke is the most debilitating cardiovascular event. It has a variety of causes that may be present simultaneously. In young or otherwise healthy people, the search for a patent foramen ovale (PFO) has become standard. In stroke of the elderly, atherosclerosis and atrial fibrillation are in the foreground but the PFO should not be ignored. The risk of a PFO-related stroke over time is controversial and so is its prevention by device closure. The association of proximal aortic plaques in arteries subtending the brain and stroke is considered strong, ignoring that it is as putative as that of the PFO. Statins can prevent progression of such plaques. Antiplatelet agents in asymptomatic and surgical endarterectomy in symptomatic patients or highly ulcerated lesions are the treatment of choice. Stenting with protection devices was shown competitive in selected patients.

Statin therapy for the prevention of atrial fibrillation: a meta-analysis of randomized controlled trials

STUDY OBJECTIVES

To assess the efficacy of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) for primary and secondary prevention of atrial fibrillation, and to evaluate the efficacy of individual statins and their dosages.

DESIGN

Meta-analysis of 20 randomized controlled trials.

PATIENTS

A total of 32,311 patients who received either a statin (16,203 patients) or a placebo or active control regimen (16,108 patients) for either primary or secondary prevention of atrial fibrillation as part of a research study.

MEASUREMENTS AND MAIN RESULTS

A systemic literature search of MEDLINE, EMBASE, and the Cochrane Controlled Trials Register was performed to identify randomized controlled trials involving the prevention of atrial fibrillation with statin therapy. Effect size was expressed as odds ratio (OR) with 95% confidence interval (CI). Subgroup analysis was performed to explore the reasons for heterogeneity. Of the 20 trials, atorvastatin was studied in 11, pravastatin in five, rosuvastatin in three, and simvastatin in one. Overall, among the 32,311 patients in these trials, the risk of atrial fibrillation was significantly reduced by statins (OR 0.59, 95% CI 0.45-0.76), and the drugs were effective for both primary prevention (OR 0.67, 95% CI 0.51-0.88) and secondary prevention (OR 0.40, 95% CI 0.20-0.83). Secondary prevention was not superior to primary prevention, however. A significant benefit was observed in the atorvastatin-treated subgroup (OR 0.43, 95% CI 0.27-0.66), especially in the dose range of 10-40 mg/day (OR 0.29, 95% CI 0.19-0.45). No protective effect was observed in the pravastatin subgroup (OR 1.03, 95% CI 0.77-1.37).

CONCLUSION

This meta-analysis suggests that statin therapy is useful for the prevention of atrial fibrillation. The benefit of statins in secondary prevention was significant but not superior to primary prevention. Atorvastatin was more effective than pravastatin, and its effects were dose related, with lower doses being more effective. The number of trials focusing on individual drugs is still insufficient, and more randomized controlled trials are necessary to further support these conclusions.

The association between serum adhesion molecules and outcome in acute spontaneous intracerebral hemorrhage

Introduction

Serum concentrations of adhesion molecules may be connected to the pathogenesis of secondary brain injury after spontaneous intracerebral hemorrhage (ICH). This study posits the hypothesis that levels of adhesion molecules substantially increase after ICH and are decreased thereafter, and that they can predict treatment outcomes.

Methods

Two hundred and thirty-nine blood samples were collected from 60 consecutive patients admitted within 24 hours after onset of spontaneous ICH and 60 blood samples were collected from 60 volunteers. Additional samples were obtained on Days 4, 7, 10, and 14 after onset of ICH regardless of clinical deterioration.

Results

Upon discharge, the therapeutic outcomes of the 60 spontaneous ICH cases based on the modified Rankin Disability Scale (mMRS) showed that 17 had no disability while 8.3% developed delayed cerebral infarction (DCI). Statistical analysis of adhesion molecules between patient groups with good outcome (mMRS = 0 or 1) and poor outcome (mMRS ≥2) revealed significant differences in diabetes mellitus (P=0.049), hyperlipidemia (P=0.012), mentality change (P=0.043), ICH volume and intraventricular hemorrhage on admission (P=0.036 and 0.006, respectively), Glasgow Coma Scale (GCS) on admission (P≤0.001), neuro-surgical intervention (P=0.003), and sE-selectin and soluble intercellular cell adhesion-molecule-1 (sICAM-1) levels on admission (P=0.036 and 0.019, respectively). Multiple logistic regression analysis of these significant variables showed that GCS on admission, hyperlipidemia, and sICAM-1 (P=0.039, 0.042, and 0.022, respectively) were independently associated with outcome of acute spontaneous ICH.

Conclusion

Increased sICAM-1 and sE-selectin levels may imply poor therapeutic outcomes for the treatment of spontaneous ICH during hospitalization. These early inflammatory responses may cause whole-brain injury immediately after spontaneous ICH and offer a potential therapeutic target for such patients. The importance of these findings is that they offer a potential therapeutic target for patients with spontaneous ICH.

Combinatorial effect of probucol and cilostazol in focal ischemic mice with hypercholesterolemia

Hypercholesterolemia may increase stroke risk by accelerating atherosclerosis, narrowing the luminal diameter in cerebral vessels, and disrupting both vascular endothelial and smooth muscle function. In the present study, we investigated the beneficial effects of combinatorial therapy with probucol and cilostazol on focal cerebral ischemia with hypercholesterolemia. Apolipoprotein E (ApoE) knockout (KO) mice were fed a high-fat diet with or without 0.5% probucol and/or 0.2% cilostazol for 10 weeks. Probucol alone and probucol and cilostazol significantly decreased total, low-density lipoprotein, and high-density lipoprotein cholesterol, whereas cilostazol did not affect the plasma cholesterol levels in ApoE KO mice. Administration of probucol alone and cilostazol alone significantly decreased atherosclerotic lesion area in the aorta, with a significant decrease evident using combinatorial administration. Middle cerebral artery occlusion resulted in significantly larger infarct volumes in ApoE KO mice fed 10 weeks of high-fat diet compared with those in ApoE KO mice fed a regular diet. The infarct volume was reduced significantly using probucol alone or cilostazol alone and even was reduced significantly by their combinatorial administration. Consistent with a larger infarct size, the combinatorial therapy prominently improved neurological function. The combinatorial administration increased cerebral blood flow during ischemia. Expression of endothelial nitric oxide synthase and adiponectin in the cortex were decreased by high-fat diet but were elevated by combinatorial treatment. Adiponectin expression colocalized within the cerebral vascular endothelium. The data suggest that the combination of probucol and cilostazol prevents cerebrovascular damage in focal cerebral ischemic mice with hypercholesterolemia by up-regulation of endothelial nitric oxide synthase and adiponectin.

Optimizing Statin Treatment Decisions for Diabetes Patients in the Presence of Uncertain Future Adherence

Background. Statins are an important part of the treatment plan for patients with type 2 diabetes. However, patients who are prescribed statins often take less than the prescribed amount or stop taking the drug altogether. This suboptimal adherence may decrease the benefit of statin initiation. Objective. To estimate the influence of adherence on the optimal timing of statin initiation for patients with type 2 diabetes. Method. The authors use a Markov decision process (MDP) model to optimize the treatment decision for patients with type 2 diabetes. Their model incorporates a Markov model linking adherence to treatment effectiveness and long-term health outcomes. They determine the optimal time of statin initiation that minimizes expected costs and maximizes expected quality-adjusted life years (QALYs). Results. In the long run, approximately 25% of patients remain highly adherent to statins. Based on the MDP model, generic statins lower costs in men and result in a small increase in costs in women relative to no treatment. Patients are able to noticeably increase their expected QALYs by 0.5 to 2 years depending on the level of adherence. Conclusions. Adherence-improving interventions can increase expected QALYs by as much as 1.5 years. Given suboptimal adherence to statins, it is optimal to delay the start time for statins; however, changing the start time alone does not lead to significant changes in costs or QALYs.

Lower levels of high-density lipoprotein cholesterol on admission and a recurrence of ischemic stroke: a 12-month follow-up of the Fukuoka Stroke Registry

BACKGROUND

Despite recent progress in treatments for secondary prevention, ischemic stroke recurs in 8% to 12% of stroke survivors. We investigated the predisposing factors associated with recurrence within the first 12 months after an ischemic event to explore more effective preventive strategies.

METHODS

Between June 2007 and April 2008, acute (within 7 days of onset) ischemic stroke patients were registered in the Fukuoka Stroke Registry (FSR), a multicenter, prospective, observational database. The clinical characteristics on admission were analyzed, and the patients were followed for 12 months.

RESULTS

Two hundred sixty patients (151 males and 109 females, 71 ± 11 years of age) were registered; 25 (9.6%) had recurrence of ischemic stroke during the follow-up period. Kaplan-Meier curve analysis revealed a significant difference in recurrence-free survival between patients with high-density lipoprotein (HDL) cholesterol <40 mg/dL on admission and those with HDL cholesterol ≥ 40 mg/dL (P = .042). Adjusted multivariate logistic regression analysis showed that age (odds ratio 1.06; 95% CI, 1.00-1.11; P = .035) and HDL cholesterol <40 mg/dL (odds ratio 2.73; 95% CI, 1.01-7.38; P = .048) on admission were independently associated with a recurrence of ischemic stroke within 12 months of the initial onset.

CONCLUSIONS

Aging and low HDL cholesterol levels are considered independent risk factors for a recurrence of ischemic stroke.

Clinical effectiveness of telmisartan alone or in combination therapy for controlling blood pressure and vascular risk in the elderly

Elderly patients (age ≥ 65 years) with hypertension are at high risk for vascular complications, especially when diabetes is present. Antihypertensive drugs that inhibit the renin-angiotensin system have been shown to be effective for controlling blood pressure in adult and elderly patients. Importantly, renin-angiotensin system inhibitors were shown to have benefits beyond their classic cardioprotective and vasculoprotective effects, including reducing the risk of new-onset diabetes and associated cardiovascular effects. The discovery that the renin-angiotensin system inhibitor and angiotensin II type 1 (AT(1)) receptor blocker (ARB), telmisartan, can selectively activate the peroxisome proliferator-activated receptor-γ (PPARγ, an established antidiabetic drug target) provides the unique opportunity to prevent and treat cardiovascular complications in high-risk elderly patients with hypertension and new-onset diabetes. Two large clinical trials, ONTARGET (Ongoing Telmisartan Alone in combination with Ramipril Global Endpoint Trial) and TRANSCEND (Telmisartan Randomized AssessmeNt Study in ACE-I iNtolerant subjects with cardiovascular disease) have assessed the cardioprotective and antidiabetic effects of telmisartan. The collective data suggest that telmisartan is a promising drug for controlling hypertension and reducing vascular risk in high-risk elderly patients with new-onset diabetes.

MicroRNA in ischemic stroke etiology and pathology

Small, noncoding, microRNAs (miRNAs) have emerged as key mediators of posttranscriptional gene silencing in both pathogenic and pathological aspects of ischemic stroke biology. In stroke etiology, miRNA have distinct expression patterns that modulate pathogenic processes including atherosclerosis (miR-21, miR-126), hyperlipidemia (miR-33, miR-125a-5p), hypertension (miR-155), and plaque rupture (miR-222, miR-210). Following focal cerebral ischemia, significant changes in the miRNA transcriptome, independent of an effect on expression of miRNA machinery, implicate miRNA in the pathological cascade of events that include blood brain barrier disruption (miR-15a) and caspase mediated cell death signaling (miR-497). Early activation of miR-200 family members improves neural cell survival via prolyl hydroxylase mRNA silencing and subsequent HIF-1α stabilization. Pro- (miR-125b) and anti-inflammatory (miR-26a, -34a, -145, and let-7b) miRNA may also be manipulated to positively influence stroke outcomes. Recent examples of successfully implemented miRNA-therapeutics direct the future of gene therapy and offer new therapeutic strategies by regulating large sets of genes in related pathways of the ischemic stroke cascade.

Optimizing lipid-lowering therapy in the prevention of coronary heart disease

Optimized lipid-lowering therapy is laid out in guidelines from national and international bodies. Statins are first-line treatment and instituted early in secondary prevention. The challenge in primary prevention is identification of the person at risk. This can be achieved by using scoring systems that assess classical risk factors, and then by adding information from predictive panels of biomarkers related to atherogenic pathways and by noninvasive imaging of vascular beds. At present, outcome trials validate the widespread use of statins in the population but studies of other agents have not generated proof of efficacy. Levels of high-density lipoprotein are related inversely to coronary heart disease risk but, so far, it is unclear if increasing high-density lipoprotein leads to a reduction in risk. Clinical trials on the utility of high-density lipoprotein raising on a background of statin therapy are underway.

Cholesterol-lowering interventions and stroke: insights from a meta-analysis of randomized controlled trials

OBJECTIVES

This meta-analysis was performed to determine the effects of various cholesterol-lowering treatments on the risk of stroke and its relationship with the extent of cholesterol lowering.

BACKGROUND

Statins reduce the incidence of stroke, and it has been proposed that such effect is independent of cholesterol lowering and is explained by alternative mechanisms.

METHODS

We performed a meta-analysis of randomized trials of cholesterol-lowering treatments in cardiovascular disease reporting on stroke, involving 266,973 patients investigated and a cumulative 946,582 person-years of exposure, and a meta-regression analysis of the extent of stroke reduction as a function of changes in total cholesterol.

RESULTS

The odds ratio (OR) for the incidence of stroke in actively treated groups versus controls was 0.88 (95% confidence interval: 0.83 to 0.94, p < 0.001). No treatment affected fatal strokes. Whereas statins decreased the risk of total stroke significantly (OR: 0.85, 95% confidence interval: 0.78 to 0.92; p < 0.001), the benefit of nonstatin interventions was smaller and not statistically significant (diet OR: 0.92, fibrates OR: 0.98, other treatments OR: 0.81). We found a significant relationship between percent reduction of total (and low-density lipoprotein) cholesterol and percent reduction of total strokes (p = 0.0017), with each 1% reduction of total cholesterol predicting a 0.8% relative risk reduction of stroke. We found no significant association between stroke reduction and changes of high-density lipoprotein cholesterol levels, and inconsistent associations with reduction of triglycerides.

CONCLUSIONS

Among cholesterol-lowering treatments, statins are the most effective at decreasing the risk of total stroke, but their benefit is proportional to the percent reduction of total cholesterol and low-density lipoprotein cholesterol. No lipid-lowering intervention was associated with a reduction of fatal stroke.

Pravastatin treatment causes a shift in the balance of hippocampal neurotransmitter binding densities towards inhibition

Since pravastatin, a HMG-CoA reductase inhibitor, has recently been shown to reduce infarct volumes and glutamate release in a rat model of ischemic stroke, the aim of the present study was to investigate whether this neuroprotective effect may be due to a modulation of excitatory and inhibitory neurotransmitter receptors. Therefore, Wistar rats were treated six times in 4 days with pravastatin or saline and allowed to survive for 6 hours or 5 days (n=10 per time point and group), respectively. Using quantitative receptor autoradiography, ligand binding densities of [(3)H]MK-801, [(3)H]AMPA, and [(3)H]muscimol for labeling of NMDA, AMPA, and GABA(A) receptors were analyzed in sensorimotor cortices Par1 and Par2, the striatum, and the hippocampus. Statin therapy induced complex alterations of ligand binding densities in different brain regions. Labeling of NMDA receptors was significantly increased in Par2, both after 6 hours and 5 days, respectively. Within the striatum, AMPA as well as GABA(A) receptor binding values were significantly increased on day 5. Furthermore, a marked and significant increase of [(3)H]muscimol ligand binding to GABA(A) receptors throughout all hippocampal subfields was seen after 6 hours. This complexity could easily be unraveled when focusing on the balance between excitatory glutamate and inhibitory GABA(A) receptors, in which case only the increase of hippocampal [(3)H]muscimol ligand binding 6 hours after the first application of pravastatin was accompanied by a net shift towards inhibition. Consequently, our data suggest an additional regulatory pathway induced by statins, namely modification of the abundance of excitatory and inhibitory neurotransmitter receptors.

Rosuvastatin in the prevention of stroke among men and women with elevated levels of C-reactive protein: justification for the Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER)

BACKGROUND

Prior primary prevention trials of statin therapy that used cholesterol criteria for enrollment have not reported significant decreases in stroke risk. We evaluated whether statin therapy might reduce stroke rates among individuals with low levels of cholesterol but elevated levels of high-sensitivity C-reactive protein.

METHODS AND RESULTS

In Justification for the Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin (JUPITER), 17 802 apparently healthy men and women with low-density lipoprotein cholesterol levels <130 mg/dL and high-sensitivity C-reactive protein levels > or = 2.0 mg/L were randomly allocated to rosuvastatin 20 mg daily or placebo and then followed up for the occurrence of a first stroke. After a median follow-up of 1.9 years (maximum, 5.0 years), rosuvastatin resulted in a 48% reduction in the hazard of fatal and nonfatal stroke as compared with placebo (incidence rate, 0.18 and 0.34 per 100 person-years of observation, respectively; hazard ratio 0.52; 95% confidence interval, 0.34 to 0.79; P=0.002), a finding that was consistent across all examined subgroups. This finding was due to a 51% reduction in the rate of ischemic stroke (hazard ratio, 0.49; 95% confidence interval, 0.30 to 0.81; P=0.004), with no difference in the rates of hemorrhagic stroke between the active and placebo arms (hazard ratio, 0.67; 95% confidence interval, 0.24 to 1.88; P=0.44).

CONCLUSIONS

Rosuvastatin reduces by more than half the incidence of ischemic stroke among men and women with low levels of low-density lipoprotein cholesterol levels who are at risk because of elevated levels of high-sensitivity C-reactive protein.

CLINICAL TRIAL REGISTRATION

clinicaltrial.gov. Unique identifier: NCT00239681.

Can we use statins to prevent stroke in Fabry disease?

Fabry disease is a rare, X-linked lysosomal storage disease caused by an inborn deficiency of alpha-galactosidase A, which results in the progressive accumulation of globotriaosylceramide and other neutral glycolipids in a range of cells and tissues. In association with the renal and cardiac insufficiency, cerebrovascular complications can result in the death of the patients. Several mechanisms causing vascular damage that leads to the development of deep-white matter lesions have been described. Recent clinical trials strongly suggest that statins protect against stroke by neuroprotective properties or pleiotropic effects.

AIM

To evaluate evidence and potential beneficial effects of statins in the vasculopathy of Fabry disease.

Interventions in the management of serum lipids for preventing stroke recurrence

BACKGROUND

Studies have shown that interventions which reduce total and low-density lipoprotein cholesterol levels also reduce coronary heart disease (CHD) and stroke events in those with a history of CHD. However, it is uncertain whether treatment to alter cholesterol levels can prevent recurrence of either stroke or subsequent cardiovascular events and whether differences in outcomes exist between classes of lipid-lowering therapy. This is an update of a Cochrane review first published in 2002.

OBJECTIVES

To investigate the effect of altering serum lipids pharmacologically for preventing subsequent cardiovascular disease and stroke recurrence in patients with a history of stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched December 2008), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2008), MEDLINE (1966 to December 2008) and EMBASE (1980 to December 2008). We contacted pharmaceutical companies known to produce a lipid-lowering agent for information on relevant publications or unpublished work.

SELECTION CRITERIA

Unconfounded randomised trials of participants aged 18 years and over with a history of stroke or transient ischaemic attack (TIA).

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed quality and extracted data.

MAIN RESULTS

We included eight studies involving approximately 10,000 participants. The active interventions were pravastatin, atorvastatin, simvastatin, clofibrate, and conjugated oestrogen. Fixed-effect analysis showed no overall effect on stroke recurrence but statin therapy alone had a marginal benefit in reducing subsequent cerebrovascular events in those with a previous history of stroke or TIA (odds ratio (OR) 0.88, 95% confidence interval (CI) 0.77 to 1.00). There was no evidence that such intervention reduced all-cause mortality or sudden death (OR 1.00, 95% CI 0.83 to 1.20). Three statin trials showed a reduction in subsequent serious vascular events (OR 0.74, 95% CI 0.67 to 0.82).

AUTHORS' CONCLUSIONS

There is evidence that statin therapy in patients with a history of ischaemic stroke or TIA significantly reduces subsequent major coronary events but only marginally reduces the risk of stroke recurrence. There is no clear evidence of beneficial effect from statins in those with previous haemorrhagic stroke and it is unclear whether statins should be started immediately post stroke or later. In view of this and the evidence of the benefit of statin therapy in those with a history of CHD, patients with ischaemic stroke or TIA, with or without a history of established CHD, should receive statins.

Oral pravastatin prolongs survival time of scrapie-infected mice

Statins are potent inhibitors of HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase in the cholesterol-biosynthesis pathway. They are either lipophilic (e.g. simvastatin) or hydrophilic [e.g. pravastatin (PRV)] compounds, considered mainly for long-term treatment of hypercholesterolaemic individuals. Beneficial effects of statins are not related exclusively to their lipid-lowering action; they also possess cholesterol-independent, pleiotropic effects (e.g. anti-inflammatory and antioxidant). Recent studies revealed that simvastatin treatment increased survival significantly in scrapie-infected mice. Although PRV treatment results in measurable drug levels in the mouse brain, the anti-prion effect of this compound has not been investigated. Therefore, we aimed to test the potential therapeutic action of PRV in a murine scrapie model. Our study showed that high-dose and long-term oral PRV treatment prolonged survival times of strain 139A scrapie-infected mice significantly (194 versus 177 days) in the absence of any obvious toxicity, suggesting that protective effects of statins may be independent of absolute solvent or water solubility of the drug.

Pravastatin for cardiovascular event primary prevention in patients with mild-to-moderate hypertension in the Management of Elevated Cholesterol in the Primary Prevention Group of Adult Japanese (MEGA) Study

Lipid-lowering therapy in individuals with high risk of cardiovascular disease reduces the incidence of coronary heart disease. However, few studies have assessed the benefits of cholesterol lowering for primary prevention of coronary heart disease in hypertensive patients with mild dyslipidemia or without conventional dyslipidemia. The large, randomized Management of Elevated Cholesterol in the Primary Prevention Group of Adult Japanese Study showed a 33% reduction in coronary heart disease incidence with pravastatin as the primary prevention in Japanese patients. We conducted an exploratory analysis of the effect of diet plus pravastatin therapy on the primary prevention of cardiovascular events (coronary heart disease, coronary heart disease plus cerebral infarction, and cardiovascular disease) in the 3277 patients with hypertension during the 5-year follow-up. There were no significant differences in mean baseline total cholesterol, blood pressure levels, or variation in blood pressure during the 5-year period between the diet (n=1664) and diet plus pravastatin (n=1613) groups. In the diet plus pravastatin group, the relative risk of coronary heart disease plus cerebral infarction was reduced by 35% (hazard ratio: 0.65; CI: 0.46 to 0.93; P=0.02), cerebral infarction by 46% (hazard ratio: 0.54; CI: 0.29 to 0.98; P=0.04), and cardiovascular disease by 33% (hazard ratio: 0.67; CI: 0.49 to 0.91; P=0.01). In patients without a history of cardiovascular disease who have hypertension and mildly elevated cholesterol, pravastatin was effective in reducing the incidence of cardiovascular disease, particularly cerebral infarction. Hence, in patients with hypertension with mildly elevated cholesterol levels, treatment with a statin is advisable to reduce the burden of cardiovascular disease.

The relationship between the effect of pravastatin and risk factors for coronary heart disease in Japanese patients with hypercholesterolemia

BACKGROUND

Several epidemiologic studies in Japan have shown the risk factors for coronary heart disease (CHD) in the general population. The present analysis determined the risk factors for CHD in the MEGA Study, a large primary prevention trial with pravastatin in Japanese with hypercholesterolemia.

METHODS AND RESULTS

The relationship between each baseline characteristic and the risk of CHD for the 5-year study period were evaluated using the Cox proportional hazard model. The multivariable predictors of CHD were sex, age, high-density lipoprotein-cholesterol (HDL-C), diabetes mellitus (DM), hypertension (HT), and history of smoking. Serum total and low-density lipoprotein-cholesterol were not independent risk factors for CHD in the current analysis. In addition, the effect of pravastatin was evaluated by subgroups in each risk factor using the interaction in a Cox model. Diet plus pravastatin treatment reduced CHD risk by 14-43% compared with diet alone, regardless of the presence or absence of risk factors.

CONCLUSIONS

The risk factors for CHD were sex, age, DM, HT, smoking, and low HDL-C in the MEGA Study. The pravastatin treatment was effective for reducing the risk of CHD, regardless of the presence of risk factors.

Statin use and risk of prostate cancer: results from a population-based epidemiologic study

Epidemiologic studies of statin use in relation to prostate cancer risk have been inconclusive. Recent evidence, however, suggests that longer-term use may reduce risk of more advanced disease. The authors conducted a population-based study of 1,001 incident prostate cancer cases diagnosed in 2002-2005 and 942 age-matched controls from King County, Washington, to evaluate risk associated with statin use. Logistic regression was used to generate odds ratios for ever use, current use, and duration of use. No overall association was found between statin use and prostate cancer risk (odds ratio (OR) = 1.0, 95% confidence interval (CI): 0.8, 1.2 for current use; OR = 1.1, 95% CI: 0.7, 1.8 for >10 years' use), even for cases with more advanced disease. Risk related to statin use, however, was modified by body mass index (interaction p = 0.04). Obese men (BMI > or =30 kg/m2) who used statins had an increased risk (OR = 1.5, 95% CI: 1.0, 2.2) relative to obese nonusers, with a stronger association for longer-term use (OR = 1.8, 95% CI: 1.1, 3.0 for > or =5 years' use). Although statin use was not associated with overall prostate cancer risk, the finding of an increased risk associated with statin use among obese men, particularly use for extended durations, warrants further investigation.

Statin Treatment and the Occurrence of Hemorrhagic Stroke in Patients With a History of Cerebrovascular Disease

Background and Purpose— The recently published Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) study showed that statins exert a marginally beneficial effect on stroke prevention in patients with a history of cerebrovascular disease. Interestingly, the magnitude of the beneficial effect shown in this study is smaller than in similar studies, which included patients without a history of cerebrovascular disease. In SPARCL, an increased occurrence of hemorrhagic strokes in patients on statin treatment was observed, an effect that was also earlier described in the Heart Protection Study in a subgroup of patients with a history of cerebrovascular disease. The purpose of this systematic review was therefore to investigate the effect of statin treatment on the occurrence of ischemic and hemorrhagic strokes in patients with a history of cerebrovascular disease.

Methods— We systematically searched the PUBMED database for the combination of the variables “statin” AND “stroke.” Furthermore, we searched for relevant studies in the Cochrane Library and Cochrane Central Register of Controlled Trials and handsearched citations. Pooled effect sizes were expressed in relative risk estimates with corresponding 95% CIs.

Results— Four studies were included investigating the effect of statins in 8832 patients with a history of cerebrovascular disease. The pooled relative risk for statin users of overall stroke during follow-up was 0.88 (95% CI: 0.78 to 0.99). The pooled relative risk of ischemic stroke was 0.80 (95% CI: 0.70 to 0.92) and of hemorrhagic stroke 1.73 (95% CI: 1.19 to 2.50).

Conclusion— In patients with a history of cerebrovascular disease, statins clearly decrease the risk of ischemic stroke. However, this beneficial effect is partly lost by an increased risk of hemorrhagic stroke.

Statin therapy in stroke prevention: a meta-analysis involving 121,000 patients

PURPOSE

More than 120,000 patients now have taken part in randomized trials evaluating statin therapy for stroke prevention. We aimed to conduct a comprehensive review of all randomized trials and determine the therapeutic potential of statins for all strokes.

METHODS

We searched 10 electronic databases (from inception to December 2006). We additionally contacted study authors and authors of previous reviews. We extracted data on study characteristics and outcomes related to all-cause mortality, all-stroke incidence, specific type of strokes, and cholesterol changes. We pooled data using a random-effects model and conducted meta-regression.

RESULTS

We included 42 trials assessing statin therapy for all-stroke prevention (n=121,285), resulting in a pooled relative risk (RR) of 0.84 (95% confidence interval [CI], 0.79-0.91). The pooled RR of statin therapy for all-cause mortality (n=116,080) was 0.88 (95% CI, 0.83-0.93). Each unit increase in low-density lipoprotein (LDL) resulted in a 0.3% increased RR of death (P=.02). Seventeen trials evaluated statins on cardiovascular death (n=57,599, RR 0.81, 95% CI, 0.74-0.90), and 11 evaluated nonhemorrhagic cerebrovascular events (n=58,604, RR 0.81, 95% CI, 0.69-0.94). Eleven trials reported hemorrhagic stroke incidence (total n=54,334, RR 0.94, 95% CI, 0.68-1.30) and 21 trials reported on fatal strokes (total n=82,278, RR 0.99, 95% CI, 0.80-1.21). Only one trial reported on statin therapy for secondary prevention.

CONCLUSIONS

Statin therapy provides high levels of protection for all-cause mortality and nonhemorrhagic strokes. This overview reinforces the need to consider prolonged statin treatment in patients at high risk of major vascular events, but caution remains for patients at risk of bleeds.

Stroke prediction and stroke prevention with atorvastatin in the Collaborative Atorvastatin Diabetes Study (CARDS)

AIMS

Patients with Type 2 diabetes have an elevated risk of stroke. The role of lipid levels and diabetes-specific factors in risk prediction of stroke is unclear, and estimates of efficacy of lipid-lowering therapy vary between trials. We examined predictors of stroke and the effect of atorvastatin on specific stroke subtypes in Type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS) [a trial of 2838 participants with mean low-density lipoprotein cholesterol < 4.14 mmol/l, no history of macrovascular disease and randomized to atorvastatin 10 mg daily or placebo].

METHODS

Median follow-up was 3.9 years. Cox regression models were used to estimate the effect of atorvastatin on stroke rate and risk of stroke associated with baseline risk factors. Risk factors that predicted stroke in univariate models were examined in a multivariable model.

RESULTS

Independent risk factors predicting stroke were age [10-year increments; hazard ratio (HR) 2.3, P < 0.001], microalbuminuria (albumin : creatinine ratio > 2.5 mg/mmol; HR 2.0, P = 0.007) and glycaemic control (HbA(1c) > 10%; HR 2.7, P = 0.007). Women were at lower risk of stroke (HR 0.3, P = 0.004). Lipids did not predict stroke. Of 60 first strokes, 47 were non-haemorrhagic, 13 were indeterminate and none was definitely haemorrhagic. Atorvastatin treatment was associated with 50% reduction in non-haemorrhagic stroke (95% confidence interval 9%-72%P = 0.024), similar to the 48% reduction (11%-69%) for all strokes combined.

CONCLUSIONS

Diabetes-specific risk factors are important predictors of stroke in Type 2 diabetes. Despite the lack of association between baseline lipids and first stroke, there was a reduction of 50% of non-haemorrhagic strokes associated with atorvastatin treatment in the CARDS population.

Diagnosis of hyperlipidemia and treatment with a statin in the outpatient stroke clinic

The aim of this study was to assess a stroke clinic's performance in the diagnosis of hyperlipidemia and more specifically to evaluate the effectiveness of statins in patients with cerebrovascular disease not enrolled in a research study. The records of 370 consecutive patients seen at a stroke clinic over a 4-year period were reviewed, and information regarding neurologic diagnosis, lipid profile, and use and type of cholesterol-lowering medication was abstracted. Hyperlipidemia was defined as a total cholesterol level equal to or more than 200 mg/dL. Forty-eight patients meeting specific criteria were further analyzed to monitor the effects of statins. Cholesterol testing was obtained in 324 patients (88%) and 178 (55%) were hyperlipidemic, but only 86 (48%) patients received treatment. The mean cholesterol level of the 48 patients dropped from 246.2 mg/dL to 197.1 mg/dL (P < .0001) after the initiation of statin therapy, and significant reductions were present in subgroups with pretreatment levels of 200 to 249 mg/dL and 250 to 299 mg/dL. Of the 21 patients with repeated cholesterol testing more than 6 months after the first posttreatment test, only 11 (52%) maintained a level below 200 mg/dL. Effective control of hyperlipidemia can be achieved in patients with cerebrovascular disease, but not all are adequately tested or treated. Improved physician awareness and more effective health care delivery systems are needed.

Effects of short term atorvastatin treatment on cerebral hemodynamics in CADASIL

BACKGROUND

HMG-CoA-reductase-inhibitors (statins) exhibit pleiotropic beneficial effects on the vascular system including induction of endothelial nitric oxide synthase (eNOS) expression which is critical for vasodilation. Recent studies suggest a beneficial effect of statins on cerebral vasoreactivity in patients with cerebral small vessel disease (SVD). CADASIL is a monogenic form of SVD caused by mutations in the Notch3 gene. Treatment options are limited and little is known about the therapeutic role of statins in CADASIL.

METHODS

Twenty-four CADASIL subjects were treated with atorvastatin for 8 weeks. Treatment was started with 40 mg, followed by a dosage increase to 80 mg after 4 weeks. Transcranial Doppler sonography measuring mean flow velocity (MFV) in the middle cerebral artery was performed at baseline and the end of the treatment period. Vasoreactivity was assessed by hypercapnia and intravenous application of l-Arginine, which is the substrate for eNOS.

RESULTS

There was no significant treatment effect on MFV (p=0.5) or cerebral vasoreactivity as assessed by hypercapnia (p=0.5) and intravenous l-Arginine (p=0.4) in the overall cohort. However, an inverse correlation was found between vasoreactivity at baseline and changes of both CO2 and l-Arginine-induced vasomotor response (both p<0.05).

CONCLUSIONS

Short term treatment with atorvastatin resulted in no significant improvement of hemodynamic parameters in the overall cohort of CADASIL subjects.

Statins: An essential component in the management of carotid artery disease

OBJECTIVE

We aimed to define the role of treatment using statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) in the management of patients with carotid artery disease.

LITERATURE SEARCH METHODS

We searched PubMed for studies evaluating the effect of statins on carotid IMT and the occurrence of cerebrovascular events.

LITERATURE SEARCH RESULTS

Current evidence indicates that routine statin therapy reduces carotid intima-media thickness progression and stroke risk. Additionally, statin treatment significantly reduces perioperative as well as long-term morbidity and mortality in patients undergoing carotid surgery or endovascular interventions. It would also be expected that statins would reduce coronary events in this high-risk population.

CONCLUSIONS

Statins should be considered as an essential component of the therapeutic approach of patients with carotid artery stenosis.

Aggressive statin therapy for acute coronary syndromes

Acute coronary syndromes (ACS) account for an enormous disease burden, especially in the Western world. Patients suffering acute coronary events are now understood to carry a very high risk of further coronary events and although improvements in conventional medical therapy over the past two decades have significantly reduced the risk, it remains high. Therapy with HMG CoA reductase inhibitors (statins) have now been well established for the primary and secondary prevention of stable coronary heart disease, but recently a substantial body of evidence has proven their efficacy in the treatment of ACS. This article examines this emerging evidence for the use of statins in ACS.

Statins and stroke prevention

Over the past decade, statins have been proven to significantly decrease coronary events in primary and secondary prevention of coronary artery disease. Recent clinical trials have indicated that statins significantly reduce stroke risk in patients with vascular disease. The Cholesterol Treatment Trialists' Collaborators in a meta-analysis including 90,056 patients found that the use of statins determined a significant 17% proportional reduction in the incidence of first-ever stroke of any type per 1 mmol/l low-density lipoprotein (LDL) cholesterol reduction. During an average of 5 years of treatment, the reduction in the overall incidence of stroke was about one sixth per 1 mmol/l LDL cholesterol decrease meaning that 8 fewer participants have any stroke per 1,000 among those with preexisting coronary artery disease at baseline, compared with 5 fewer per 1,000 among the participants with no such history. It is not known whether these findings might be due to the cholesterol reduction effect of statins or to pleiotropic effects of statins, such as improved endothelial function, decreased platelet aggregability, and reduced vascular inflammation. In secondary prevention of stroke, the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) study found that treatment with atorvastatin reduced the risk of recurrent cerebrovascular events in patients with recent stroke or transient ischemic attack but no history of heart disease. Combining the results of patients with no history of heart disease from the SPARCL study and Heart Protection Study in a mini meta-analysis, compared with placebo, statins were associated with a barely nonsignificant difference in recurrent stroke (OR = 0.87, 95% CI = 0.75-1.01, p = 0.07) and a significant difference in the occurrence of major vascular events (OR = 0.78, 95% CI = 0.68-0.88, p = 0.0001) at final follow-up.

Histopathology of carotid atherosclerotic disease

Stroke is the third leading cause of death in the United States, constituting approximately 700,000 cases each year, of which about 500,000 are first attacks and 200,000 are recurrent attacks. Ischemic stroke accounts for the majority of all strokes (88%), followed by intracerebral hemorrhage (9%) and subarachnoid hemorrhage (3%). Patients with substantial carotid narrowing are at increased risk for major stroke; however, recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis. Atherosclerotic plaque of the stenotic carotid artery is the underlying cause of the majority of ischemic strokes and specific plaque characteristics have been associated with ischemic brain injury. Several studies have demonstrated that the mechanisms of plaque instability in the carotid circulation are similar to those in the coronary circulation. The purpose of this review is to characterize atherosclerotic carotid disease in light of our knowledge of coronary atherosclerosis and relate carotid plaque morphology to cerebral ischemic syndromes. Histological examination of the carotid plaque specimen should provide insights into the underlying plaque morphology that is responsible for the disease and should help determine the potential treatments that are likely to be beneficial in the prevention of a subsequent event.

A pravastatin dose-escalation study in systemic lupus erythematosus

Statin medications have been suggested for widespread use in patients with systemic lupus erythematosus (SLE). We studied the dose effectiveness and tolerability of pravastatin in SLE. We compared 41 SLE subjects in a two-month open-label dose-titration study of pravastatin to 22 SLE controls. Lipids, ALT, CPK, CRP, adverse effects were assessed. Linear mixed models assessed changes in lipids and CRP, comparing pravastatin subjects to controls. After 1 month of pravastatin 10 mg a day, total cholesterol decreased by 16% (+/-12.1%) and LDL by 24% (+/-17%), compared with 1.8% (+/-7.5%) and 2.6% (+/-8.6%) decreases in controls (P < 0.001). CRP did not decline. Glucocorticoids appeared to decrease pravastatin effectiveness. Serum CPK increased in one subject. Pravastatin reduced LDL and total cholesterol levels approximately the same degree observed in normal individuals, but the effect appeared blunted in those on modest doses of glucocorticoids and those with higher BMI.

Lipid levels and the risk of ischemic stroke in women

OBJECTIVE

To evaluate the association between total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol to HDL-C ratio, and non-HDL-C with the risk of ischemic stroke in a large cohort of apparently healthy women.

METHODS

Prospective cohort study among 27,937 US women aged > or =45 years participating in the Women's Health Study who provided baseline blood samples. Stroke occurrence was self-reported and confirmed by medical record review. We categorized plasma lipid measurements into quintiles. We used Cox proportional hazards models to evaluate the association between lipids and risk of ischemic stroke.

RESULTS

During 11 years of follow-up, 282 ischemic strokes occurred. All lipid levels were strongly associated with increased risk of ischemic stroke in age-adjusted models. The association attenuated particularly for HDL-C after adjustment for potential confounders. For the comparison of the highest to the lowest quintile, the multivariable-adjusted hazard ratios (95% CI; p for trend across mean quintile values) of ischemic stroke were 2.27 (1.43, 3.60; p(trend) < 0.001) for total cholesterol; 1.74 (1.14, 2.66; p(trend) = 0.003) for LDL-C; 0.78 (0.52, 1.17; p(trend) = 0.27) for HDL-C; 1.65 (1.06, 2.58; p(trend) = 0.02) for the total cholesterol to HDL-C ratio; and 2.45 (1.54, 3.91; p(trend) < 0.001) for non-HDL-C.

CONCLUSIONS

In this large cohort of apparently healthy women, total cholesterol, low-density lipoprotein cholesterol, the total cholesterol to high-density lipoprotein cholesterol ratio, and non-high-density lipoprotein cholesterol were significantly associated with increased risk of ischemic stroke.

Mechanisms of action of statins in stroke

Statins decrease the incidence of cardiovascular events and death in patients with coronary artery disease. Moreover, the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) study has recently demonstrated that high-dose atorvastatin may also reduce the recurrence of stroke in patients with previous stroke or transitory ischemic attack.

Prevention of stroke and dementia by statin therapy: Experimental and clinical evidence of their pleiotropic effects

Stroke and dementia are major causes of disability in most countries. Epidemiological studies have demonstrated that statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) are likely to reduce the risk for developing these formidable disorders. The favorable outcomes in statin users may be attributable to not only cholesterol-dependent actions, but also various cholesterol-independent actions called "pleiotropic effects." Several clinical trials have suggested that statins decrease the incidence of stroke, especially ischemic stroke. Statins improve endothelial function, inhibit platelet activation, reduce blood coagulability, and suppress inflammatory reactions, all of which may contribute to the beneficial effects of the therapy. Statins also reduce the risk of vasospasm caused by subarachnoid hemorrhage (SAH). In addition, statins might inhibit the development and progression of Alzheimer's disease (AD), the dominant type of dementia in most industrialized countries, upstream of the amyloid cascade. In vitro studies have shown that statins modulate the metabolism of the beta-amyloid precursor protein (APP) and reduce the extracellular level of its proteolytic product, amyloid-beta (Abeta). The aggregated Abeta is cytotoxic, leading to formation of neurofibrillary tangles and neuronal loss in the brain. Inflammatory processes are active in AD and may contribute significantly to AD pathology. We review the experimental background regarding the pleiotropic effects of statins and summarize clinical trials that examined the preventative effects of statin therapy on stroke and dementia. We include current trials in which statin therapy is initiated within 24 hr of onset of acute ischemic stroke.

Beyond lipid lowering: What have we learned about the benefits of statins from the acute coronary syndromes trials?

The long-term benefits for prevention of primary and secondary cardiovascular events achieved by lowering serum cholesterol levels with statins are undisputed. However, results of early clinical trials and preclinical studies suggested the possibility that benefits of treatment with the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) may not be entirely due to their effects on low-density lipoprotein (LDL) cholesterol. Since then, large-scale clinical trials of statin treatment for acute coronary syndromes (ACS) have demonstrated early benefits that are associated with aggressive initiation of statin therapy. Support for pleiotropic effects of statins in these trials has been provided not only by these acute effects but also by apparent differences in efficacy between various statin regimens that seem unrelated to their effects on serum cholesterol levels. Analyses of biomarkers of inflammation, oxidation, and thrombosis in samples from patients in these studies have also suggested possible mechanisms underlying the benefits of statins in ACS. This article reviews some of the key statin trials in ACS and assesses the evidence for benefits of these drugs independent of their effects on LDL cholesterol.

Common Questions in Managing Hyperlipidemia

Hyperlipidemia is a serious disease that affects the health and well-being of many, and further complicates other chronic illnesses. When treating a patient who has a lipid disorder, it is wise to take a global approach to the problem by assessing the patient's history and risk factors, collaborating on developing a healthy lifestyle plan to which the patient can commit, and initiating appropriate therapy when indicated.

Statin therapy for coronary heart disease and its effect on stroke

Coronary heart disease (CHD) and stroke share common risk factors and are the leading causes of death and disability in the United States. Although the impact of elevated cholesterol on stroke risk has been disputed, numerous trials using 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors (ie, statins) in patients with CHD have demonstrated a significant reduction in stroke incidence as a secondary endpoint. It is likely that statins are pleiotropic in stroke prevention, providing benefits through both cholesterol reduction and cholesterol-independent mechanisms. In this article, we review the relationship between cholesterol and stroke, randomized trials of statins in patients with CHD and high risk for CHD that have assessed stroke risk, and the putative mechanisms of stroke prevention by statins.