Showing papers by "Peter J. Koudstaal published in 2009"

Genomewide Association Studies of Stroke

Abstract: BACKGROUND: The genes underlying the risk of stroke in the general population remain undetermined. METHODS: We carried out an analysis of genomewide association data generated from four large cohorts composing the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium, including 19,602 white persons (mean [±SD] age, 63±8 years) in whom 1544 incident strokes (1164 ischemic strokes) developed over an average follow-up of 11 years. We tested the markers most strongly associated with stroke in a replication cohort of 2430 black persons with 215 incident strokes (191 ischemic strokes), another cohort of 574 black persons with 85 incident strokes (68 ischemic strokes), and 652 Dutch persons with ischemic stroke and 3613 unaffected persons. RESULTS: Two intergenic single-nucleotide polymorphisms on chromosome 12p13 and within 11 kb of the gene NINJ2 were associated with stroke (P<5×10-8). NINJ2 encodes an adhesion molecule expressed in glia and shows increased expression after nerve injury. Direct genotyping showed that rs12425791 was associated with an increased risk of total (i.e., all types) and ischemic stroke, with hazard ratios of 1.30 (95% confidence interval [CI], 1.19 to 1.42) and 1.33 (95% CI, 1.21 to 1.47), respectively, yielding population attributable risks of 11% and 12% in the discovery cohorts. Corresponding hazard ratios were 1.35 (95% CI, 1.01 to 1.79; P = 0.04) and 1.42 (95% CI, 1.06 to 1.91; P = 0.02) in the large cohort of black persons and 1.17 (95% CI, 1.01 to 1.37; P = 0.03) and 1.19 (95% CI, 1.01 to 1.41; P = 0.04) in the Dutch sample; the results of an underpowered analysis of the smaller black cohort were nonsignificant. CONCLUSIONS: A genetic locus on chromosome 12p13 is associated with an increased risk of stroke.

Statins are associated with a reduced risk of Alzheimer disease regardless of lipophilicity. The Rotterdam Study.

Abstract: Background: Cross-sectional reports suggest that statin users are less likely to have Alzheimer disease (AD). Prospective studies have provided inconsistent evidence. Moreover, it is unclear whether the association differs for lipohilic statins, those that could more easily pass the blood–brain barrier and hydrophilic statins. Objectives: To prospectively evaluate whether use of statins is associated with the risk of AD, and to determine whether associations differ for lipophilic and hydrophilic statins. Method: 6992 participants of the prospective, population-based Rotterdam Study were followed, from baseline (1990–1993) until January 2005 for incident AD. Data on all filled prescriptions came from pharmacy records. For each date on which each event occurred, cholesterol-lowering drug use for the person who experienced the event and all remaining persons in the cohort was categorised as “any” or “never” use. A distinction was made between statin, lipophilic and hydrophilic statins, and non-statin cholesterol-lowering drugs. Data were analysed with the Cox regression analysis, adjusting for sex, age and potential confounders. Results: During follow-up (mean 9 years), 582 persons developed AD. Compared with never use of cholesterol-lowering drugs, statin use was associated with a decreased risk of AD (HR 0.57; 95% CI 0.37 to 0.90), but non-statin cholesterol-lowering drug use was not (HR 1.05; 95% CI 0.45 to 2.44). HRs were equal for lipophilic (HR 0.54; 95% CI 0.32 to 0.89) and hydrophilic statins (HR 0.54; 95% CI 0.26 to 1.11). Conclusion: In the general population, the use of statins, but not of non-statin cholesterol-lowering drugs, was associated with a lower risk of AD compared with never use of cholesterol-lowering drugs. The protective effect was independent of the lipophilicity of statins.

Effect of Age on Stroke Prevention Therapy in Patients With Atrial Fibrillation: The Atrial Fibrillation Investigators

Abstract: Background and Purpose - Stroke risk increases with age in patients who have nonvalvular atrial fibrillation. It is uncertain whether the efficacy of stroke prevention therapies in atrial fibrillation changes as patients age. The objective of this study was to determine the effect of age on the relative efficacy of oral anticoagulants (OAC) and antiplatelet (AP) therapy (including acetylsalicylic acid and triflusal) on ischemic stroke, serious bleeding, and vascular events in patients with atrial fibrillation. Methods - This is an analysis of the Atrial Fibrillation Investigators database, which contains patient level-data from randomized trials of stroke prevention in atrial fibrillation. We used Cox regression models with age as a continuous variable that controlled for sex, year of randomization, and history of cerebrovascular disease, diabetes, hypertension, and congestive heart failure. Outcomes included ischemic stroke, serious bleeding (intracranial hemorrhage or systemic bleeding requiring hospitalization, transfusion, or surgery), and cardiovascular events (ischemic stroke, myocardial infarction, systemic embolism, or vascular death). Results - The analysis included 8932 patients and 17 685 years of observation from 12 trials. Patient age increased risk of ischemic stroke (adjusted hazard ratio per decade increase 1.45; 95% CI, 1.26 to 1.66), serious bleeding (1.61; 1.47 to 1.77), and cardiovascular events (1.43; 1.33 to 1.53). Compared with placebo, OAC and AP significantly reduced the risk of ischemic stroke (OAC, 0.36; 0.29 to 0.45; AP, 0.81; 0.72 to 0.90) and cardiovascular outcomes (OAC, 0.59; 0.52 to 0.66; AP, 0.81; 0.75 to 0.88), whereas OAC increased risk of serious bleeding (1.56; 1.03 to 2.37). The relative benefit of OAC versus placebo or AP did not vary by patient age for any outcome. Compared with placebo, the relative benefit of AP for preventing ischemic stroke decreased significantly as patients aged (P=0.01). Conclusions - As patients with atrial fibrillation age, the relative efficacy of AP to prevent ischemic stroke appears to decrease, whereas it does not change for OAC. Because stroke risk increases with age, the absolute benefit of OAC increases as patients get older. © 2009 American Heart Association, Inc.

The Paracetamol (Acetaminophen) In Stroke (PAIS) trial: a multicentre, randomised, placebo-controlled, phase III trial

Abstract: Summary Background High body temperature in the first 12–24 h after stroke onset is associated with poor functional outcome. The Paracetamol (Acetaminophen) In Stroke (PAIS) trial aimed to assess whether early treatment with paracetamol improves functional outcome in patients with acute stroke by reducing body temperature and preventing fever. Methods In a multicentre, randomised, double-blind, placebo-controlled trial, patients with ischaemic stroke or intracerebral haemorrhage and body temperature between 36°C and 39°C were randomly assigned treatment with paracetamol (6 g daily) or placebo within 12 h from symptom onset. Treatment allocation was based on a computer-generated list of random numbers with varying block size. The primary outcome was improvement beyond expectation on the modified Rankin scale at 3 months, according to the sliding dichotomy approach. This trial is registered, number ISRCTN74418480. Findings Between March, 2003, and May, 2008, 1400 patients were randomly allocated treatment. 260 (37%) of 697 patients receiving paracetamol and 232 (33%) of 703 receiving placebo improved beyond expectation (adjusted odds ratio [OR] 1·20, 95% CI 0·96–1·50). In a post-hoc analysis of patients with baseline body temperature 37–39°C, treatment with paracetamol was associated with improved outcome (1·43, 1·02–1·97). There were 55 serious adverse events in the paracetamol group (8%) and 70 in the placebo group (10%). Interpretation These results do not support routine use of high-dose paracetamol in patients with acute stroke. Paracetamol might have a beneficial effect on functional outcome in patients admitted with a body temperature 37–39°C, but this post-hoc finding needs further study. Funding Netherlands Heart Foundation.

Postconcussion syndrome after minor head injury: brain activation of working memory and attention.

Abstract: After minor head injury (MHI) postconcussive symptoms (PCS) such as memory and attention deficits frequently occur. It has been hypothesised that PCS are caused by microstructural damage to the brain due to shearing injury, which is not detectable with conventional imaging, and may be responsible for a functional deficit. The purpose of this study was to correlate functional magnetic resonance imaging brain activation of working memory and selective attention with PCS. 21 MHI patients and 12 healthy controls were scanned at 3T. Stimulation paradigms were the n-back and Counting Stroop tasks to engage working memory and selective attention, respectively. Functional data analysis consisted of random effects group analyses, correlating brain activation patterns with the severity of PCS as evaluated with the Rivermead postconcussion symptoms questionnaire. At minimal working memory load, activation was seen in patients with greater severity of PCS in the working memory network. With an increase of working memory load, increase of activation was more pronounced in patients with greater severity of PCS. At high and increased working memory load, activation associated with the severity of PCS was seen in the posterior parietal area, parahippocampal gyrus, and posterior cingulate gyrus. Activation related to selective attention processing was increased with greater severity of PCS. The increased activity in relation to working memory and attention, and the recruitment of brain areas outside the working memory network at high working memory load, may be considered a reflection of the brain's compensatory response to microstructural injury in patients with PCS.

Duration of antihypertensive drug use and risk of dementia: A prospective cohort study

Abstract: Background: The evidence from prospective observational research for a protective effect of antihypertensive drug use on the risk of dementia is far from uniform. Duration of follow-up was limited and relied mainly on baseline drug exposure data without information on duration of use. We investigated the association between the duration of antihypertensive use and risk of dementia. Methods: We followed 6,249 participants (mean 68.4 years, 60% women) of a prospective, population-based cohort from baseline (1990–1993) until 2005 for incident dementia. Continuous data on filled prescriptions came from pharmacy records. Total cumulative duration of antihypertensive use was expressed in years. We subtracted a latent 4-year period before the date of dementia diagnosis in the quantification of exposure duration to avoid potential bias in antihypertensive prescription due to prodromal changes in blood pressure or cognition. With Cox regression models, we calculated crude and adjusted hazard ratios (HRs) of all dementia and Alzheimer disease (AD) with antihypertensive use vs never used. Results: Compared to never used, antihypertensive use was associated with a reduced risk of all dementia (adjusted HR per year of use 0.95; 95% confidence interval [CI] 0.91–0.99). We observed an 8% (95% CI −15% to −1%) risk reduction per year of use for persons ≤75 years, whereas for persons >75 years this was 4% (95% CI −11% to 4%). Equivalent estimates were observed for AD. No apparent differences were observed among different types of antihypertensive drugs. Conclusions: Antihypertensive drug use was associated with 8% risk reduction of dementia per year of use for persons ≤75 years.

C-reactive protein in the very early phase of acute ischemic stroke: association with poor outcome and death

Abstract: Acute ischemic stroke may trigger an inflammatory response that leads to increased levels of C-reactive protein (CRP). High levels of CRP may be associated with poor outcome because they reflect either an inflammatory reaction or tissue damage. We evaluated the prognostic value of CRP within 12 h of onset of ischemic stroke. Levels of CRP were routinely obtained within 12 h of symptom onset in 561 patients with ischemic stroke. CRP values were dichotomized as 2) or death at 3 months. A multiple logistic regression model was applied to adjust for age, sex, NIHSS score, current cigarette smoking, diabetes mellitus, hypertension, statin use, and stroke subtype. After adjustment for potential confounders, patients with CRP levels ≥7 mg/L had a significantly increased risk of poor outcome (adjusted OR 1.6, 95% CI 1.1–2.4) or death (adjusted OR 1.7, 95% CI 1.0–2.9) at 3 months. In addition, the risk of poor outcome or death at 3 months increased with higher levels of CRP. CRP within 12 h of ischemic stroke is an independent prognostic factor of poor outcome at 3 months.

Patients Enrolled in Large Randomized Clinical Trials of Antiplatelet Treatment for Prevention After Transient Ischemic Attack or Ischemic Stroke Are Not Representative of Patients in Clinical Practice The Netherlands Stroke Survey

Abstract: Background and Purpose—Many randomized clinical trials have evaluated the benefit of long-term use of antiplatelet drugs in reducing the risk of new vascular events in patients with a recent transient ischemic attack or ischemic stroke. Evidence from these trials forms the basis for national and international guidelines for the management of nearly all such patients in clinical practice. However, abundant and strict enrollment criteria may limit the validity and the applicability of results of randomized clinical trials to clinical practice. We estimated the eligibility for participation in landmark trials of antiplatelet drugs of an unselected group of patients with stroke or transient ischemic attack from a national stroke survey. Methods—Nine hundred seventy-two patients with transient ischemic attack or ischemic stroke were prospectively and consecutively enrolled in the Netherlands Stroke Survey. We applied 7 large antiplatelet trials’ enrollment criteria. Results—In total, 886 patients were discharg...

Predicting and preventing stroke after transient ischemic attack

Abstract: The prognosis of transient ischemic attacks (TIAs) is not as favorable as previously thought. Given a risk of stroke of approximately 10% in the first week following a TIA, urgent evaluation and initiation of treatment are required. Recently developed scores to predict the early risk of subsequent stroke in individual patients may guide treatment decisions in the acute phase. Lately it has become clear that transient attacks with nonfocal symptoms are not benign either, as these were found to be associated with an increased risk of vascular disease. The significance of this finding and its implications for treatment are not yet clear. There is substantial evidence from a number of clinical trials that adequate secondary prevention therapies can reduce the risk of stroke after TIA. In addition to the conventional vascular risk factors, interest has grown in less strong but more prevalent lifestyle factors, but trials evaluating the effect of modifying these factors are as yet lacking.

Impact of early surgery after aneurysmal subarachnoid haemorrhage.

Abstract: OBJECTIVES: To investigate the effect of early aneurysm surgery ( 13]. We used multivariable logistic regression analysis to assess outcome at 3 months. RESULTS: Favourable outcome (Glasgow Outcome Scale 4 or 5) was similar in both cohorts. Cerebral ischemia occurred significantly more often in the ES cohort. The occurrence of rebleeds was similar in both cohorts. External cerebrospinal fluid (CSF) drainage was performed more often in the ES cohort (51% vs 19%). Patients with cisternal sum score (CSS) of subarachnoid blood 12 on admission benefited from the strategy including ES (OR 10.5, 95% CI 1.1-99.4). CONCLUSIONS: Our results support the widely adopted practice of ES in good-grade SAH patients.