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Mitchell S V Elkind

Publications and source records attributed to Mitchell S V Elkind.

At least 19 recordsLinked to original sources

Seropositivity to Chlamydia pneumoniae is associated with risk of first ischemic stroke.

BACKGROUND AND PURPOSE: Serologic evidence of infection with Chlamydia pneumoniae has been associated with cardiovascular disease, but its relationship with stroke risk remains uncertain. The objective of this study is to determine whether serological evidence of C pneumoniae infection is associated with risk of ischemic stroke. METHODS: A population-based case-control study was performed in an urban, multiethnic population. Cases (n=246) had first ischemic stroke, and controls (n=474) matched for age, sex, and race-ethnicity were derived through random-digit dialing. Titers of C pneumoniae-specific IgG and IgA antibodies were measured using microimmunofluorescence, and positive titers were prospectively defined. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% CIs adjusting for medical, behavioral, and socioeconomic factors. RESULTS: Mean age among cases was 72.3+/-9.7 years; 50.8% were women. Elevated C pneumoniae IgA titers were associated with increased risk of ischemic stroke after adjusting for hypertension, diabetes mellitus, current cigarette use, atrial fibrillation, and levels of high-density lipoprotein and low-density lipoprotein (adjusted OR, 1.5; 95% CI, 1.0 to 2.2). Elevated IgG titers were not associated with stroke risk (adjusted OR, 1.2; 95% CI, 0.8 to 1.8). There was a trend toward an association of elevated IgA titers with atherosclerotic and lacunar stroke but less so cardioembolic or cryptogenic subtypes. CONCLUSIONS: Serologic evidence of C pneumoniae infection is associated with ischemic stroke risk. IgA titers may be a better marker of risk than IgG. This association is independent of other stroke risk factors and is present for atherosclerotic, lacunar, and cardioembolic subtypes. Further studies of the effect of C pneumoniae on stroke risk are warranted.

Aged↗

Outpatient training in neurology: history and future challenges.

The organization of neurology as a specialty and of neurology training specifically has evolved tremendously over the last 130 years. Originally primarily an outpatient specialty, the focus of training shifted to inpatient neurology in the early 20th century when accreditation of programs required training in newly established inpatient-based neurologic departments. Now and in the near future, the growth of neurologic critical care and the expansion of neurology intensive care units may require even more inpatient responsibilities in neurology residency programs. Contrary to these trends in training, most community neurology practice is still focused on outpatients, and surveys of neurologists have consistently indicated a need for more outpatient exposure in neurology training. This article briefly reviews the history of neurology training, discusses current challenges to outpatient training, and recommends possible solutions for the future.

Ambulatory Care Facilities↗

Moderate alcohol consumption reduces risk of ischemic stroke: the Northern Manhattan Study.

BACKGROUND AND PURPOSE: Moderate alcohol consumption is protective against coronary disease, but its relationship to ischemic stroke (IS) is controversial. METHODS: Stroke-free participants > or =40 years of age identified by random-digit dialing were enrolled in a prospective cohort study between 1993 and 2001. Alcohol consumption was assessed through in-person interview and categorized as none in the past year, > or =1 drink in past month to < or =2 per day (moderate drinkers), and >2 drinks daily. Lifetime drinking was also assessed. Cox proportional hazard regression modeling was used to assess hazard ratios and their 95% CIs for the association of drinking with risk of stroke and vascular events. RESULTS: Mean age among participants (n=3176) was 69.1+/-10.3 years; 62.8% were women, 20.8% were non-Hispanic white, 24.5% non-Hispanic black, and 52.4% were Hispanic. No alcohol in the previous year was present in 62.3%, and 32.5% drank moderately. After adjusting for other risk factors compared with those who did not drink in the past year, moderate drinkers had a reduced risk of IS (0.67; 95% CI, 0.46 to 0.99) and IS, myocardial infarction, or vascular death (0.74; 95% CI, 0.59 to 0.94). Results were similar when never-drinkers were used as referent group. Reduction in risk was seen for nonatherosclerotic IS subtypes, and results stratified by age, sex, and race-ethnicity were similar. CONCLUSIONS: Moderate alcohol consumption is associated with decreased risk of IS in a multiethnic population. This effect is independent of other risk factors and holds for nonatherosclerotic stroke subtypes.

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Lipid-lowering agent use at ischemic stroke onset is associated with decreased mortality.

BACKGROUND: 3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins), the most frequently used lipid-lowering agents (LLAs) have neuroprotective effects in rodent models of ischemic stroke. The authors hypothesized that patients with ischemic stroke taking LLAs would have better outcomes than patients not taking LLAs. METHODS: The Northern Manhattan Study is a population-based study designed to determine stroke incidence and prognosis in a multiethnic, urban population. Northern Manhattan residents age 40 years or older diagnosed with their first ischemic stroke were eligible. Patients or their proxies were interviewed regarding medications being taken at home before stroke onset. The NIH Stroke Scale was used to assess stroke severity, categorized as mild (< or =5), moderate (6 to 13), or severe (> or =14), and the Barthel Index at 6 months to assess functional outcome. Clinical worsening in hospital was recorded by trial neurologists. Odds ratios and 95% CIs for association of LLA use and stroke severity, mortality, and functional outcome were calculated using logistic regression. RESULTS: Of 650 patients, 57 (8.8%) were taking LLAs. The majority (90.9%) of LLA users were taking a statin. Clinical worsening in hospital occurred less frequently among patients taking LLAs at stroke onset (6.3% vs 18.2%; p = 0.04). Ninety-day mortality was lower in those taking LLAs (1.8% vs 10.6%, p = 0.03). The proportion of patients with severe stroke among those taking LLAs was not lower (10.7% vs 16.8%, p = 0.39). CONCLUSION: Patients taking lipid-lowering agents (LLAs) at the time of an ischemic stroke may have lower poststroke mortality and a lower risk of worsening during hospitalization. Prospective studies are warranted to determine whether LLAs, and statins in particular, have neuroprotective properties or other beneficial effects in acute ischemic stroke.

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Implications of stroke prevention trials: treatment of global risk.

Clinical trials have demonstrated that risk of cardiovascular events may be reduced in patients with stroke, using blood pressure (BP) reduction and statin therapy, independently of the presence of specific risk factors. These results suggest an alternative approach to secondary stroke prevention, focused more on global risk than on detection and modification of individual categorical risk factors such as hypertension, dyslipidemia, and diabetes mellitus. A risk-based approach is warranted because stroke patients are at high risk of several cardiovascular events, not just stroke, and because physiologic risk factors such as BP demonstrate a continuous, or log-linear, relationship with cardiovascular risk. Essential to the implementation of such an approach is the development of adequate risk stratification models for stroke patients. Based on limited available evidence, however, it appears that most patients who experience an ischemic stroke or TIA are at high long-term absolute risk of a subsequent cardiovascular event and should be treated with all available risk-reduction strategies.

Antihypertensive Agents↗

Ischemic stroke subtype incidence among whites, blacks, and Hispanics: the Northern Manhattan Study.

BACKGROUND: Stroke incidence is greater in blacks than in whites; data on Hispanics are limited. Comparing subtype-specific ischemic stroke incidence rates may help to explain race-ethnic differences in stroke risk. The aim of this population-based study was to determine ischemic stroke subtype incidence rates for whites, blacks, and Hispanics living in one community. METHODS AND RESULTS: A comprehensive stroke surveillance system incorporating multiple overlapping strategies was used to identify all cases of first ischemic stroke occurring between July 1, 1993, and June 30, 1997, in northern Manhattan. Ischemic stroke subtypes were determined according to a modified NINDS scheme, and age-adjusted, race-specific incidence rates calculated. The annual age-adjusted incidence of first ischemic stroke per 100,000 was 88 (95% CI, 75 to 101) in whites, 149 (95% CI, 132 to 165) in Hispanics, and 191 (95% CI, 160 to 221) in blacks. Among blacks compared with whites, the relative rate of intracranial atherosclerotic stroke was 5.85 (95% CI, 1.82 to 18.73); extracranial atherosclerotic stroke, 3.18 (95% CI, 1.42 to 7.13); lacunar stroke, 3.09 (95% CI, 1.86 to 5.11); and cardioembolic stroke, 1.58 (95% CI, 0.99 to 2.52). Among Hispanics compared with whites, the relative rate of intracranial atherosclerotic stroke was 5.00 (95% CI, 1.69 to 14.76); extracranial atherosclerotic stroke, 1.71 (95% CI, 0.80 to 3.63); lacunar stroke, 2.32 (95% CI, 1.48 to 3.63); and cardioembolic stroke, 1.42 (95% CI, 0.97 to 2.09). CONCLUSIONS: The high ischemic stroke incidence among blacks and Hispanics compared with whites is due to higher rates of all ischemic stroke subtypes.

Black or African American↗

Leukocyte count is associated with reduced endothelial reactivity.

BACKGROUND: Leukocyte count has been associated with cardiovascular and cerebrovascular disease in several studies. We hypothesized that white blood cell count is associated with endothelial reactivity. METHODS AND RESULTS: Leukocyte count was measured in a sample of stroke-free community participants undergoing brachial artery testing for endothelial reactivity. Flow-mediated dilation (FMD) during reactive hyperemia was assessed in each subject using high-resolution B-mode ultrasound. Multivariate linear regression was used to calculate the effect of leukocyte count on endothelial reactivity after adjusting for potential confounding factors. Mean age of the 868 participants was 66.7+/-8.8 years; 57% were women. Mean leukocyte count was (6.1+/-1.8)x10(9)/L. Each unit increase in leukocyte count was associated with a mean 0.18% decrease in FMD (p = 0.01). After adjusting for other atherosclerosis risk factors, including age, sex, hypertension, diabetes, hyperlipidemia, and smoking, the relationship persisted (mean decrease in FMD per unit leukocyte count = 0.17%, p = 0.02). There was a linear decrease in FMD by quartile of leukocyte count (p = 0.0014). The effect of leukocyte count on FMD was greater for women, those under age 70, and non-diabetics. CONCLUSIONS: Relative elevations in leukocyte count are associated with a reduction in brachial artery endothelial reactivity. These findings are consistent with current hypotheses regarding the inflammatory or infectious etiology of risk of atherosclerosis and stroke, but also suggest interactions with demographic and other risk factors.

Aged↗

Radiographic measures of chronic periodontitis and carotid artery plaque.

BACKGROUND AND PURPOSE: Chronic periodontitis (CP) is associated with stroke and subclinical atherosclerosis, but clinical measurement of CP can be time consuming and invasive. The purpose of this study was to determine whether radiographically assessed CP is associated with nonstenotic carotid artery plaque as an ultrasound measure of subclinical atherosclerosis. METHODS: Panoramic oral radiographs were obtained from 203 stroke-free subjects ages 54 to 94 during the baseline examination of the Oral Infections and Vascular Disease Epidemiology Study (INVEST). CP exposure among dentate subjects was defined either categorically (periodontal bone loss > or =50% [severe] versus <50% bone loss) or via tertile formation (for dose-response investigation), with edentulous subjects categorized separately. In all subjects, high-resolution B-mode carotid ultrasound was performed. Carotid plaque thickness (CPT) and prevalence (present/absent) were recorded. Covariates included age, sex, smoking, diabetes, hypertension, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol. RESULTS: Among dentate subjects with severe periodontal bone loss, mean CPT was significantly greater (1.20+/-1.00 mm versus 0.73+/-0.89 mm; P=0.003). CPT increased with more severe bone loss (upper versus lower tertile bone loss; P=0.049; adjusted for age, sex, and hypertension). This apparent dose-response effect was more evident among never-smokers. In a fully adjusted multivariate logistic regression model, severe periodontal bone loss was associated with a nearly 4-fold increase in risk for the presence of carotid artery plaque (adjusted odds ratio, 3.64; CI, 1.37 to 9.65). CONCLUSIONS: Severe periodontal bone loss is associated independently with carotid atherosclerosis. Panoramic oral radiographs may thus provide an efficient means to assess CP in studies of atherosclerosis risk.

Aged↗

Interleukin-2 levels are associated with carotid artery intima-media thickness.

OBJECTIVE: To show that serum interleukin levels are associated with carotid intima-media thickness (IMT). BACKGROUND: Inflammation is hypothesized to play a central role in atherogenesis, and serum markers of inflammation are predictive of cardiovascular disease. Interleukin-2, a pro-inflammatory cytokine produced largely by naive CD4 T cells and Th1 (pro-inflammatory) T cells, has been found in a high proportion of carotid plaques. METHODS: High-resolution ultrasound of the carotid arteries and serum cytokine levels were measured in stroke-free participants. The mean of the maximum IMT in bilateral bifurcation, common and internal carotid artery segments was measured. Serum levels of interleukin (IL)-1beta, IL-2, IL-6, C-reactive protein, tumor necrosis factor (TNF) alpha and TNF receptors were measured using enzyme-linked immunosorbent assay. RESULTS: IL-2 levels were significantly correlated with IMT (r=0.33, P<0.0001), but other cytokines were not. Each unit increase in IL-2 was significantly associated with a mean increase in IMT of 0.18 mm (P=0.0001). After adjusting for other atherosclerotic risk factors, the association was unchanged (mean increase in IMT per unit increase IL-2=0.18 mm, P<0.0001). Each standard deviation increase in the level of IL-2 was associated with an increased risk (adjusted odds ratio 1.80, 95% CI 1.12-2.89) for an IMT> or =1.0mm (75th percentile for IMT). CONCLUSION: Serum levels of IL-2, a pro-inflammatory cytokine, are associated with carotid artery IMT, a predictor of stroke and vascular disease. Serum inflammatory markers may provide a novel marker of atherosclerotic risk, and inflammation may provide a new therapeutic target for stroke prevention.

Aged↗

Magnetic resonance imaging changes in a patient with migraine attack and transient global amnesia after cardiac catheterization.

The presence of magnetic resonance imaging (MRI) abnormalities in patients with transient global amnesia has been an interesting phenomenologic finding. Several theories surround the occurrence of this syndrome, but little is known about its true physiopathology. We present a case of transient global amnesia after cardiac catheterization associated with migraine headache and MRI changes compatible with an ischemic insult. A discussion on potential explanations for this finding is made, as well as a review of the pertinent literature.

Amnesia, Transient Global↗

Hemicraniectomy for massive middle cerebral artery territory infarction: a systematic review.

BACKGROUND AND PURPOSE: Hemicraniectomy and durotomy have been proposed in many small series to relieve intracranial hypertension and tissue shifts in patients with large hemispheric infarcts, thereby preventing death from herniation. Our objective was to review the literature to identify patients most likely to benefit from hemicraniectomy. METHODS: All available individual cases from the English literature were reviewed and analyzed to determine whether age, vascular territory of infarction, side of infarction, reported time to surgery, and signs of herniation predict outcome in patients after hemicraniectomy. All studies included were retrospective and uncontrolled; there were no randomized controlled trials. RESULTS: Of 15 studies screened, 12 studies describing 129 patients met the criteria for analysis; 9 patients treated at our institution were added, for a total of 138 patients. After a minimum follow-up of 4 months, 10 patients (7%) were functionally independent, 48 (35%) were mildly to moderately disabled, and 80 (58%) died or were severely disabled. Of 75 patients who were >50 years of age, 80% were dead or severely disabled compared with 32% of 63 patients <or=50 years of age (P<0.00001). The timing of surgery, hemisphere infarcted, presence of signs of herniation before surgery, and involvement of other vascular territories did not significantly affect outcome. CONCLUSIONS: Age may be a crucial factor in predicting functional outcome after hemicraniectomy in patients with large middle cerebral artery territory infarction.

Adult↗

Secondary stroke prevention: review of clinical trials.

Patients who experience a stroke or transient ischemic attack (TIA) are at high risk for subsequent vascular events, most commonly stroke. This article focuses on clinical trials examining secondary prevention of stroke and reviews the various commonly used methods of stroke prevention: surgical approaches, antihypertensive treatment, lipid- and cholesterol-lowering medications, anticoagulant therapies, and antiplatelet therapies.

Anticoagulants↗

The role of warfarin and aspirin in secondary prevention of stroke.

Antithrombotic therapy plays a central role in secondary prevention after ischemic stroke and transient ischemic attack. The choice among warfarin, aspirin, and other antiplatelet agents, however, depends on the cause of stroke and other individual patient characteristics. The use of warfarin anticoagulation in patients with atrial fibrillation and ischemic stroke has demonstrated robust reductions in risk of recurrent events, comparable with those achieved in primary prevention. Warfarin may also be recommended for patients with other high-risk cardioembolic sources of stroke. The role of warfarin in noncardioembolic ischemic stroke is more controversial. The Warfarin Aspirin Recurrent Stroke Study found no evidence of superiority of warfarin over aspirin in stroke patients overall, nor in any major stroke subtype, including those patients with patent foramen ovale. In post-hoc analyses, there was some evidence of benefit with warfarin in patients with cryptogenic stroke without hypertension. Risks of major bleeding did not differ significantly between warfarin and aspirin groups. For most patients with noncardioembolic strokes, therefore, antiplatelet therapy is the preferred option, although clinician experience still dictates practice in individual situations. Newer antiplatelet agents, and the combination of novel agents with aspirin, are also finding a role in stroke prevention as clinical trial data become available.

Anticoagulants↗