Ischemic Stroke and Secondary Prevention in Clinical Practice

Statin therapy and outcome after ischemic stroke: systematic review and meta-analysis of observational studies and randomized trials

BACKGROUND AND PURPOSE

Although experimental data suggest that statin therapy may improve neurological outcome after acute cerebral ischemia, the results from clinical studies are conflicting. We performed a systematic review and meta-analysis investigating the relationship between statin therapy and outcome after ischemic stroke.

METHODS

The primary analysis investigated statin therapy at stroke onset (prestroke statin use) and good functional outcome (modified Rankin score 0 to 2) and death. Secondary analyses included the following: (1) acute poststroke statin therapy (≤ 72 hours after stroke), and (2) thrombolysis-treated patients.

RESULTS

The primary analysis included 113 148 subjects (27 studies). Among observational studies, statin treatment at stroke onset was associated with good functional outcome at 90 days (pooled odds ratio [OR], 1.41; 95% confidence interval [CI], 1.29-1.56; P<0.001), but not 1 year (OR, 1.12; 95% CI, 0.9-1.4; P=0.31), and with reduced fatality at 90 days (pooled OR, 0.71; 95% CI, 0.62-0.82; P<0.001) and 1 year (OR, 0.80; 95% CI, 0.67-0.95; P=0.01). In the single randomized controlled trial reporting 90-day functional outcome, statin treatment was associated with good outcome (OR, 1.5; 95% CI, 1.0-2.24; P=0.05). No reduction in fatality was observed on meta-analysis of data from 3 randomized controlled trials (P=0.9). In studies restricted to of thrombolysis-treated patients, an association between statins and increased fatality at 90 days was observed (pooled OR, 1.25; 95% CI, 1.02-1.52; P=0.03, 3 studies, 4339 patients). However, this association was no longer present after adjusting for age and stroke severity in the largest study (adjusted OR, 1.14; 95% CI, 0.90-1.44; 4012 patients).

CONCLUSIONS

In the largest meta-analysis to date, statin therapy at stroke onset was associated with improved outcome, a finding not observed in studies restricted to thrombolysis-treated patients. Randomized trials of statin therapy in acute ischemic stroke are needed.

Oral anticoagulant and antiplatelet drugs used in prevention of cardiovascular events in elderly people in Poland

BACKGROUND

In Poland, the prevalence of cardiovascular diseases is increasing. This might be associated with the constantly growing proportion of elderly people and inappropriate cardiovascular prevention. This study aimed to evaluate the frequency of use of oral antiplatelet (OAP) and oral anticoagulant (OAC) drugs among older people in Poland and to assess their association with cardiovascular risk factors.

METHODS

The study was based on data collected during the implementation of a multicentre, publicly funded research project called PolSenior.

RESULTS

The study group consisted of 4,979 people with the average age of 79.35 ± 8.69 years. Among them, 1,787 people (35.9%) used at least one drug in the prevention of cardiovascular diseases. OAPs were used regularly by 1,648 (33.1%) elderly people and OACs were used by 165 elderly people (3.3%). Acetylsalicylic acid was used by 32.2% of elderly people. Use of drugs significantly depended on age (p < 0.01), sex (p < 0.01), place of residence (p < 0.001), level of education (p < 0.0001) and personal income (p < 0.0001). Among all the respondents treated with OAPs, therapy was applied as secondary cardiovascular prevention in 717 respondents (43.5%), and as primary prevention in 705 respondents (42.8%). Among the respondents treated with OACs, 117 (71%) elderly people had a history of atrial fibrillation. Secondary cardiovascular prevention should be considered in a further 482 respondents (15.1% of untreated elderly people), and primary cardiovascular prevention in 1,447 respondents (45.3%).

CONCLUSIONS

Our study is the first to determine the frequency of use of OAP and OAC drugs among elderly people in Poland in relation to cardiovascular risk factors. The most commonly used drug for cardiovascular prevention is acetylsalicylic acid, but it appears that it is used too rarely in high-risk patients. Educational programs should be developed among general practitioners concerning current recommendations for pharmacological cardiovascular prevention.

Reduced Risk of Death with Warfarin – Results of an Observational Nationwide Study of 20 442 Patients with Atrial Fibrillation and Ischaemic Stroke

Background

Warfarin is demonstrated to be superior in efficacy over antiplatelet agents for the prevention of stroke, but the relationship between warfarin and mortality is less clear. Our aim was to investigate this relationship in a large cohort of unselected patients with atrial fibrillation and ischaemic stroke.

Methods

This observational study was based on patients who were discharged alive and registered in the Swedish Stroke Register in 2001 through 2005. Vital status was retrieved by linkage to the Swedish Cause of Death Register. We calculated a propensity score for the likelihood of warfarin prescription at discharge from hospital. The risk of death and 95% confidence intervals were estimated in Cox regression models.

Results

Out of the 20 442 patients with atrial fibrillation and ischaemic stroke (mean age = 79·5 years), 31% ( n = 6399) were prescribed warfarin. After adjustment for the propensity score, warfarin was associated with a reduced risk of death (0·67; 95% confidence interval, 0·63–0·71). The crude rate (per 100 person-years) of fatal non-haemorrhagic stroke was lower in patients who received warfarin (1·60; 95% confidence interval, 1·34–1·89) compared to those who received antiplatelet (6·83; 95% confidence interval, 6·42–7·25). The rates (per 100 person-years) of fatal haemorrhagic stroke were 0·21 (95% confidence interval, 0·12–0·32) and 0·43 (95% confidence interval, 0·34–0·55) in patients prescribed warfarin and antiplatelet therapy, respectively.

Conclusions

In addition to its established benefit for stroke prevention, warfarin therapy in patients with atrial fibrillation and ischaemic stroke was associated with a reduced risk of death, without an increased risk of fatal haemorrhagic stroke.

Non-invasive optical imaging of stroke

The acute onset of a neurological deficit is the key clinical feature of stroke. In most cases, however, pathophysiological changes in the cerebral vasculature precede the event, often by many years. Persisting neurological deficits may also require long-term rehabilitation. Hence, stroke may be considered a chronic disease, and diagnostic and therapeutic efforts must include identification of specific risk factors, and the monitoring of and interventions in the acute and subacute stages, and should aim at a pathophysiologically based approach to optimize the rehabilitative effort. Non-invasive optical techniques have been experimentally used in all three stages of the disease and may complement the established diagnostic and monitoring tools. Here, we provide an overview of studies using the methodology in the context of stroke, and we sketch perspectives of how they may be integrated into the assessment of the highly dynamic pathophysiological processes during the acute and subacute stages of the disease and also during rehabilitation and (secondary) prevention of stroke.

First-ever atrial fibrillation documented after hemorrhagic or ischemic stroke: the role of the CHADS(2) score at the time of stroke

BACKGROUND

The CHADS(2) score (C, congestive heart failure [CHF]; H, hypertension [HT]; A, age ≥75 y; D, diabetes mellitus; S(2) , prior stroke or transient ischemic attack) is used to assess the risk of ischemic stroke in patients with atrial fibrillation (AF). However, its role in patients without documented AF is not well explored.

HYPOTHESIS

The goal of the current study was to explore if the incidence of hospitalization with first-ever AF after stroke increased with increasing CHADS(2) score.

METHODS

We identified 57636 patients with nonfatal stroke and no documented AF in the Swedish Stroke Register (Riks-Stroke) during 2001-2004 and followed them for a mean of 2.2 years through record linkage to the Inpatient and Cause of Death registers. Cox regression hazard models were used to estimate the relative risk (RR) of new AF following stroke and its association with different CHADS(2) scores.

RESULTS

Overall, 2769 patients were hospitalized with new AF (4.8%, 21.7 per 1000 person-years). The incidence increased from 9.6 per 1000 person-years in CHADS(2) score 0 to 42.7 in CHADS(2) score 6, conferring a RR of 4.2 (95% confidence interval [CI]: 2.5-6.8). For CHADS(2) scores 3-5, the RRs were approximately 3 (vs CHADS(2) score 0). Adjusted RRs were 1.9 (95% CI: 1.7-2.1) for CHF, 1.4 (95% CI: 1.3-1.5) for HT, 2.1 (95% CI: 2.0-2.3) for age ≥75 years, 0.9 (95% CI: 0.8-1.0) for diabetes, and 1.0 (95% CI: 0.91-1.07) for previous stroke. The risk of AF was higher in ischemic than in hemorrhagic stroke.

CONCLUSIONS

In this retrospective register study, the incidence of AF following stroke was strongly influenced by higher CHADS(2) scores where age ≥75 years, CHF, and HT were the contributing CHADS(2) components.