Lymphocyte Subsets in the Adrenal Glands of Dogs With Primary Hypoadrenocorticism

Primary hypoadrenocorticism, or Addison's disease, is an autoimmune condition common in certain dog breeds that leads to the destruction of the adrenal cortex and a clinical syndrome involving anorexia, gastrointestinal upset, and electrolyte imbalances. Previous studies have demonstrated that this destruction is strongly associated with lymphocytic-plasmacytic inflammation and that the lymphocytes are primarily T cells. In this study, we used both immunohistochemistry and in situ hybridization to characterize the T-cell subtypes involved. We collected postmortem specimens of 5 dogs with primary hypoadrenocorticism and 2 control dogs and, using the aforementioned techniques, showed that the lymphocytes are primarily CD4+ rather than CD8+. These findings have important implications for improving our understanding of the pathogenesis and in searching for the underlying causative genetic polymorphisms.

Stroke Performance Measures Do Not Predict Functional Outcome

BACKGROUND AND PURPOSE

Poststroke functional outcome is critical to stroke survivors. We sought to determine whether adherence to current stroke performance measures is associated with better functional outcome 90 days after an ischemic stroke.

METHODS

Utilizing the Brain Attack Surveillance in Corpus Christi cohort, we examined adherence to 7 ischemic stroke performance measures from February 2009 to June 2012. Adherence to the measures was analyzed in aggregate using a binary defect-free score and an opportunity score, representing the proportion of eligible measures met. The opportunity score ranges from 0 to 1, with values closer to 1 implying better adherence. Functional outcome, defined by an activities of daily living and instrumental activities of daily living (ADL/IADL) score (range 1-4, higher scores worse), was ascertained at 90 days poststroke. Tobit regression models were fitted to examine the associations between the performance measures and functional outcome, adjusting for demographic and clinical characteristics, including stroke severity.

RESULTS

There were 565 patients with ischemic stroke included in the analysis. The median ADL/IADL score was 2.32 (interquartile range [IQR]: 1.41-3.41). The median opportunity score was 1 (IQR: 0.8-1), and 58.4% of the patients received defect-free care. After adjustment, the opportunity score (P = .67) and defect-free care (P = .92) were not associated with functional outcome.

CONCLUSION

In this population, adherence to a composite of current stroke performance measures was not associated with poststroke functional outcome after adjustment for other factors. Performance measures that are associated with improved functional outcome should be developed and incorporated into stroke quality measures.

Genetic variants in CETP increase risk of intracerebral hemorrhage

Objective

In observational epidemiologic studies, higher plasma high‐density lipoprotein cholesterol (HDL‐C) has been associated with increased risk of intracerebral hemorrhage (ICH). DNA sequence variants that decrease cholesteryl ester transfer protein (CETP) gene activity increase plasma HDL‐C; as such, medicines that inhibit CETP and raise HDL‐C are in clinical development. Here, we test the hypothesis that CETP DNA sequence variants associated with higher HDL‐C also increase risk for ICH.

Methods

We performed 2 candidate‐gene analyses of CETP. First, we tested individual CETP variants in a discovery cohort of 1,149 ICH cases and 1,238 controls from 3 studies, followed by replication in 1,625 cases and 1,845 controls from 5 studies. Second, we constructed a genetic risk score comprised of 7 independent variants at the CETP locus and tested this score for association with HDL‐C as well as ICH risk.

Results

Twelve variants within CETP demonstrated nominal association with ICH, with the strongest association at the rs173539 locus (odds ratio [OR] = 1.25, standard error [SE] = 0.06, p = 6.0 × 10⁻⁴) with no heterogeneity across studies (I² = 0%). This association was replicated in patients of European ancestry (p = 0.03). A genetic score of CETP variants found to increase HDL‐C by ∼2.85mg/dl in the Global Lipids Genetics Consortium was strongly associated with ICH risk (OR = 1.86, SE = 0.13, p = 1.39 × 10⁻⁶).

Interpretation

Genetic variants in CETP associated with increased HDL‐C raise the risk of ICH. Given ongoing therapeutic development in CETP inhibition and other HDL‐raising strategies, further exploration of potential adverse cerebrovascular outcomes may be warranted. Ann Neurol 2016;80:730–740

Expiratory Positive Airway Pressure for Sleep Apnea after Stroke: A Randomized, Crossover Trial

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is common after stroke and predicts poor outcomes. Continuous positive airway pressure (CPAP) treats OSA but is generally poorly tolerated by stroke patients. We assessed whether nasal expiratory positive airway pressure (EPAP), an alternative to CPAP, may be an effective option after acute stroke.

METHODS

We conducted a randomized, controlled, two-period crossover study in which each acute ischemic stroke patient received 1 night of EPAP and 1 night without EPAP while OSA was monitored with a validated device, the Watch-PAT 200. Linear repeated- measures analyses were conducted. Sample size calculations indicated that 18 subjects would be required to detect a 10-point or larger average reduction in the apnea-hypopnea index (AHI, the primary outcome), with use of EPAP, with power ≥ 80% and α = 0.05.

RESULTS

Among the 19 subjects who completed the protocol, nasal EPAP treatment was associated with a nonsignificant absolute difference in AHI of -5.73 events/h in the primary analysis (p = 0.183, 95% confidence interval -14.4, 2.97) and a nonsignificant absolute difference in AHI of -5.43 events/h in the subgroup of patients who used nasal EPAP for ≥ 3 h (p = 0.314, 95% confidence interval -16.6, 5.76).

CONCLUSIONS

This study suggests that EPAP is not an effective alternative to CPAP in acute stroke patients with OSA. Further work is needed to identify other more effective alternatives.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT01703663.

Trial of early noninvasive ventilation for ALS: A pilot placebo-controlled study

OBJECTIVE

To evaluate the use and tolerability of noninvasive positive pressure ventilation (NIV) in patients with amyotrophic lateral sclerosis (ALS) early in their disease by comparing active NIV and sham NIV in patients not yet eligible for NIV use as recommended by practice guidelines.

METHODS

This was a single-center, prospective, double-blind, randomized, placebo (sham)-controlled pilot trial. Patients with ALS were randomized to receive either sham NIV or active NIV and underwent active surveillance approximately every 3 months until they reached a forced vital capacity (FVC) <50% or required NIV for clinical symptom management.

RESULTS

In total, 54 participants were randomized. The mean NIV use was 2.0 hours (95% confidence interval [CI] 1.1-3.0) per day in the sham NIV treatment group and 3.3 hours (CI 2.0-4.6) per day in the active NIV group, which did not differ by treatment group (p = 0.347). The majority of sham NIV participants (88%) and active NIV participants (73%) reported only mild or no problem with NIV use. Difference of change in FVC through the treatment period by group (0.44 per month) favored active NIV (p = 0.049). Survival and changes in maximal inspiratory or expiratory pressure did not differ between treatment groups.

CONCLUSIONS

The efficacy of early NIV in ALS should be tested in randomized, placebo-controlled trials. The trial is registered on clinicaltrials.gov (NCT00580593).

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for patients with ALS, adherence with NIV and sham NIV are similar.

Mesenchymal Hamartoma of the Liver in a Late-Term Equine Fetus

Mesenchymal hamartoma of the liver is a rare congenital disorder of biliary tract development. During the necropsy of a late-term equine fetus, a markedly enlarged liver of more than two times normal weight was found. Light microscopic review revealed that the normal hepatic parenchyma had been obliterated, replaced, and expanded by abnormal bile ducts surrounded by abundant, myxoid stroma. The lesion was diagnosed as a mesenchymal hamartoma. Small portions of the liver had bridging septa of fibrosis and proliferations of small-caliber abnormal bile ducts, resembling another congenital biliary abnormality termed congenital hepatic fibrosis.

The Association between Changes in Behavioral Risk Factors for Stroke and Changes in Blood Pressure

BACKGROUND

High blood pressure (BP) is the leading risk factor for stroke. Data on the association of physical activity (PA), fruit and vegetable (F&V) consumption, and dietary sodium with hypertension are lacking in Hispanic communities. In the current report, we provide data on the association between changes in these stroke behavioral risk factors and BP change.

METHODS

Participants were recruited from participating Catholic churches in Nueces County, Texas. BP was measured, and self-reported validated scales of F&V consumption, dietary sodium, and PA were collected at baseline and at 12 months. Linear mixed models were used to examine the associations between tertiles of improvement in the 3 behavior outcomes and BP change, adjusted for demographic characteristics. The association between the binary measure of at least 5 mmHg diastolic blood pressure (DBP) or 10 mmHg systolic blood pressure (SBP) reduction and behavior change was estimated with multilevel logistic regression models.

RESULTS

Of 586 participants, 66% were female and 82% were Mexican American (MA), and the mean age was 54 years. High compared with low change in PA was significantly associated with DBP change (P = .022), and high compared with low change in F&V intake was significantly associated with SBP change (P = .032). For the binary changes in DBP or SBP, there was a borderline association of PA (P = .054); all other variables were not associated (P > .10).

CONCLUSIONS

PA and F&V consumption are potential stroke prevention targets in predominantly MA populations.

Mexican Americans are Less Likely to Return to Work Following Stroke: Clinical and Policy Implications

BACKGROUND

Greater poststroke disability and U.S. employment policies may disadvantage minority stroke survivors from returning to work. We explored ethnic differences in return to work among Mexican Americans (MAs) and non-Hispanic whites (NHWs) working at the time of their stroke.

METHODS

Stroke patients were identified from the population-based BASIC (Brain Attack Surveillance in Corpus Christi) study from August 2011 to December 2013. Employment status was obtained at baseline and 90-day interviews. Sequential logistic regression models were built to assess ethnic differences in return to work after accounting for the following: (1) age (<65 versus ≥65); (2) sex; (3) 90-day National Institutes of Health Stroke Scale (NIHSS); and (4) education (lower than high school versus high school or higher).

RESULTS

Of the 729 MA and NHW stroke survivors who completed the baseline interview, 197 (27%) were working at the time of their stroke, of which 125 (63%) completed the 90-day outcome interview. Forty-nine (40%) stroke survivors returned to work by 90 days. MAs were less likely to return to work (OR = .45, 95% CI .22-.94) than NHWs. The ethnic difference became nonsignificant after adjusting for NIHSS (OR = .59, 95% CI .24-1.44) and further attenuated after adjusting for education (OR = .85, 95% CI .32- 2.22).

CONCLUSIONS

The majority of stroke survivors did not return to work within 90 days of their stroke. MA stroke survivors were less likely to return to work after stroke than NHW stroke survivors which was due to their greater neurological deficits and lower educational attainment compared with that of NHW stroke survivors. Future work should focus on clinical and policy efforts to reduce ethnic disparities in return to work.

Stroke risk stratification in acute dizziness presentations: A prospective imaging-based study

OBJECTIVE

To estimate the ability of bedside information to risk stratify stroke in acute dizziness presentations.

METHODS

Surveillance methods were used to identify patients with acute dizziness and nystagmus or imbalance, excluding those with benign paroxysmal positional vertigo, medical causes, or moderate to severe neurologic deficits. Stroke was defined as acute infarction or intracerebral hemorrhage on a clinical or research MRI performed within 14 days of dizziness onset. Bedside information comprised history of stroke, the ABCD(2) score (age, blood pressure, clinical features, duration, and diabetes), an ocular motor (OM)-based assessment (head impulse test, nystagmus pattern [central vs other], test of skew), and a general neurologic examination for other CNS features. Multivariable logistic regression was used to determine the association of the bedside information with stroke. Model calibration was assessed using low (<5%), intermediate (5% to <10%), and high (≥10%) predicted probability risk categories.

RESULTS

Acute stroke was identified in 29 of 272 patients (10.7%). Associations with stroke were as follows: ABCD(2) score (continuous) (odds ratio [OR] 1.74; 95% confidence interval [CI] 1.20-2.51), any other CNS features (OR 2.54; 95% CI 1.06-6.08), OM assessment (OR 2.82; 95% CI 0.96-8.30), and prior stroke (OR 0.48; 95% CI 0.05-4.57). No stroke cases were in the model's low-risk probability category (0/86, 0%), whereas 9 were in the moderate-risk category (9/94, 9.6%) and 20 were in the high-risk category (20/92, 21.7%).

CONCLUSION

In acute dizziness presentations, the combination of ABCD(2) score, general neurologic examination, and a specialized OM examination has the capacity to risk-stratify acute stroke on MRI.

A Multicomponent Behavioral Intervention to Reduce Stroke Risk Factor Behaviors: The Stroke Health and Risk Education Cluster-Randomized Controlled Trial

BACKGROUND AND PURPOSE

The Stroke Health and Risk Education Project was a cluster-randomized, faith-based, culturally sensitive, theory-based multicomponent behavioral intervention trial to reduce key stroke risk factor behaviors in Hispanics/Latinos and European Americans.

METHODS

Ten Catholic churches were randomized to intervention or control group. The intervention group received a 1-year multicomponent intervention (with poor adherence) that included self-help materials, tailored newsletters, and motivational interviewing counseling calls. Multilevel modeling, accounting for clustering within subject pairs and parishes, was used to test treatment differences in the average change since baseline (ascertained at 6 and 12 months) in dietary sodium, fruit and vegetable intake, and physical activity, measured using standardized questionnaires. A priori, the trial was considered successful if any one of the 3 outcomes was significant at the 0.05/3 level.

RESULTS

Of 801 subjects who consented, 760 completed baseline data assessments, and of these, 86% completed at least one outcome assessment. The median age was 53 years; 84% subjects were Hispanic/Latino; and 64% subjects were women. The intervention group had a greater increase in fruit and vegetable intake than the control group (0.25 cups per day [95% confidence interval: 0.08, 0.42], P=0.002), a greater decrease in sodium intake (-123.17 mg/d [-194.76, -51.59], P=0.04), but no difference in change in moderate- or greater-intensity physical activity (-27 metabolic equivalent-minutes per week [-526, 471], P=0.56).

CONCLUSIONS

This multicomponent behavioral intervention targeting stroke risk factors in predominantly Hispanics/Latinos was effective in increasing fruit and vegetable intake, reaching its primary end point. The intervention also seemed to lower sodium intake. Church-based health promotions can be successful in primary stroke prevention efforts.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01378780.

Ethnic Differences in Poststroke Quality of Life in the Brain Attack Surveillance in Corpus Christi (BASIC) Project

BACKGROUND AND PURPOSE

Mexican Americans (MAs) have an increased risk of stroke and experience worse poststroke disability than non-Hispanic whites, which may translate into worse poststroke quality of life (QOL). We assessed ethnic differences in poststroke QOL, as well as potential modification of associations by age, sex, and initial stroke severity.

METHODS

Ischemic stroke survivors were identified through the biethnic, population-based Brain Attack Surveillance in Corpus Christi (BASIC) Project. Data were collected from medical records, baseline interviews, and 90-day poststroke interviews. Poststroke QOL was measured at ≈90 days by the validated short-form stroke-specific QOL in 3 domains: overall, physical, and psychosocial (range, 0-5; higher scores represent better QOL). Tobit regression was used to model associations between ethnicity and poststroke QOL scores, adjusted for demographics, clinical characteristics, and prestroke cognition and function.

RESULTS

Among 290 eligible stroke survivors (66% MA, 34% non-Hispanic whites, median age=69 years), median scores for overall, physical, and psychosocial poststroke QOL were 3.3, 3.8, and 2.7, respectively. Poststroke QOL was lower for MAs than non-Hispanic whites both overall (mean difference, -0.30; 95% confidence interval, -0.59, -0.01) and in the physical domain (mean difference, -0.47; 95% confidence interval, -0.81, -0.14) after multivariable adjustment. No ethnic difference was found in the psychosocial domain. Age modified the associations between ethnicity and poststroke QOL such that differences were present in older but not in younger ages.

CONCLUSIONS

Disparities exist in poststroke QOL for MAs and seem to be driven by differences in older stroke patients. Targeted interventions to improve outcomes among MA stroke survivors are urgently needed.

Rare Coding Variation and Risk of Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Intracerebral hemorrhage has a substantial genetic component. We performed a preliminary search for rare coding variants associated with intracerebral hemorrhage.

METHODS

A total of 757 cases and 795 controls were genotyped using the Illumina HumanExome Beadchip (Illumina, Inc, San Diego, CA). Meta-analyses of single-variant and gene-based association were computed.

RESULTS

No rare coding variants were associated with intracerebral hemorrhage. Three common variants on chromosome 19q13 at an established susceptibility locus, encompassing TOMM40, APOE, and APOC1, met genome-wide significance (P<5e-08). After adjusting for the APOE epsilon alleles, this locus was no longer convincingly associated with intracerebral hemorrhage. No gene reached genome-wide significance level in gene-based association testing.

CONCLUSIONS

Although no coding variants of large effect were detected, this study further underscores a major challenge for the study of genetic susceptibility loci; large sample sizes are required for sufficient power except for loci with large effects.

The pharmacokinetic/pharmacodynamic rationale for administering vancomycin via continuous infusion

WHAT IS KNOWN AND OBJECTIVE

Vancomycin is administered via intermittent infusion (II) almost exclusively in the United States, whereas continuous infusion (CI) dosing methods are used regularly in many European countries. The purpose of this literature analysis is to review current evidence regarding the advantages and disadvantages of CI vancomycin in relation to II, based on the pharmacokinetic and pharmacodynamic aspects of dosing and monitoring therapy, and to identify current practices of CI vancomycin dosing.

METHODS

Medline, Cochrane and GoogleScholar databases were searched using vancomycin as a MeSH term, along with continuous and infusion in all fields, which identified 136 citations. A second search added the terms intermittent and survey, producing nine additional articles. All articles that reported an assessment of CI or II vancomycin administration in adult patients, based on clinical, pharmacokinetic, cost or monitoring considerations, were identified. A total of 43 publications were determined to be suitable for final analysis and possible inclusion in the report.

RESULTS AND DISCUSSION

A meta-analysis of six studies concluded that CI vancomycin was associated with a lower relative risk of kidney injury than II therapy, although other studies reported equivocal findings. The results of several clinical studies suggest that CI vancomycin produces clinical outcomes that are comparable to II. Current vancomycin consensus guidelines promote aggressive dosing to achieve trough levels of 10-15 or 15-20 mg/L, but also include recommendations to target a daily area under the curve (AUC24 ) to minimum inhibitory concentration (MIC) ratio of at least 400. Because vancomycin is a non-concentration-dependent antibiotic, it might be more prudent to monitor steady-state serum concentrations (Css ) during a CI rather than trough concentrations during II, due to the questionable correlation between measured trough concentration and AUC. From a pharmacokinetic/pharmacodynamic perspective, vancomycin dosing and monitoring practices associated with CI offer potentially greater reliability than II. A major disadvantage of CI involves the possibility of having to intravenously co-administer another drug that might not be compatible with vancomycin.

WHAT IS NEW AND CONCLUSION

Continuous infusion vancomycin therapy offers the advantage of Css monitoring, thus avoiding the variabilities associated with the timing of trough levels. Current CI practices include a loading dose of 15-20 mg/kg followed by an infusion of 10-40 mg/kg/day based on the patient's renal function, with a target Css of about 20-30 mg/L. An alternative approach to weight-based (mg/kg) CI dosing is to calculate the dose from an estimation of the patient's vancomycin clearance (in L/h), derived from creatinine clearance (CrCl) via the equation (CrCl∙0·041) + 0·22. The daily dose is then determined by multiplying vancomycin clearance (in L/h) by the desired AUC24 . A new CI vancomycin dosing chart includes clearance-based dosing recommendations for Css values ranging from 17·5 to 27·5 mg/L or AUC24 values ranging from 420 to 660 mg h/L. Although sufficient data already exist to support the use of CI vancomycin as a reasonable therapeutic alternative to II, there is still much to learn about administering the drug in this fashion.

Adolescent knowledge and attitudes related to clinical trials

Background or aims

Poor enrollment plagues most clinical trials. Furthermore, despite mandates to improve minority representation in clinical trial participation, little progress has been made. We investigated the knowledge and attitudes of adolescents related to clinical trials and made race/ethnicity comparisons in an attempt to identify a possible educational intervention target.

Methods

Students aged 13–18 years in southeast Michigan were offered participation through a class at one high school or two academic summer enrichment programs that drew from multiple high schools (73% response). Questionnaires previously validated in adults were administered. Non-Hispanic whites were compared with minorities using Wilcoxon rank-sum tests.

Results

Of the 82 respondents, the median age was 16 years (interquartile range: 15–17 years); 22 (28%) were white, 41 (51%) were African American, 11 (14%) were multiracial, 2 (2%) were American Indian or Alaska Native, 1 (1%) was Asian, 3 (4%) were Native Hawaiian or other Pacific Islander, and 2 respondents did not report a race (but did report Hispanic ethnicity). Nine (12%) were Hispanic. Only 27 (33%) had ever heard of a clinical trial. On a scale from 1 (most receptive) to 5 (least receptive) for learning more about a clinical trial for a relevant medical condition, the median score was 2 (interquartile range: 1–3) and for participating in a clinical trial for a relevant medical condition was 2 (interquartile range: 2–3). Overall knowledge was poor, with a median of 46% (interquartile range: 23%−62%) of knowledge answers correct. Knowledge was reduced (p = 0.0006) and attitudes were more negative (p = 0.05) in minorities than non-Hispanic whites, while minorities also endorsed more substantial barriers to trial participation (p = 0.0002). Distrust was similar between minority students and non-Hispanic whites (p = 0.15), and self-efficacy was greater in non-Hispanic whites (p = 0.05).

Conclusion

Educational interventions directed toward adolescents that address knowledge, attitudes, and distrust in order to improve clinical trial awareness and receptivity overall are needed and may represent a tool to address disparities in minority enrollment in clinical trials.

Common variation in COL4A1/COL4A2 is associated with sporadic cerebral small vessel disease

OBJECTIVES

We hypothesized that common variants in the collagen genes COL4A1/COL4A2 are associated with sporadic forms of cerebral small vessel disease.

METHODS

We conducted meta-analyses of existing genotype data among individuals of European ancestry to determine associations of 1,070 common single nucleotide polymorphisms (SNPs) in the COL4A1/COL4A2 genomic region with the following: intracerebral hemorrhage and its subtypes (deep, lobar) (1,545 cases, 1,485 controls); ischemic stroke and its subtypes (cardioembolic, large vessel disease, lacunar) (12,389 cases, 62,004 controls); and white matter hyperintensities (2,733 individuals with ischemic stroke and 9,361 from population-based cohorts with brain MRI data). We calculated a statistical significance threshold that accounted for multiple testing and linkage disequilibrium between SNPs (p < 0.000084).

RESULTS

Three intronic SNPs in COL4A2 were significantly associated with deep intracerebral hemorrhage (lead SNP odds ratio [OR] 1.29, 95% confidence interval [CI] 1.14-1.46, p = 0.00003; r(2) > 0.9 between SNPs). Although SNPs associated with deep intracerebral hemorrhage did not reach our significance threshold for association with lacunar ischemic stroke (lead SNP OR 1.10, 95% CI 1.03-1.18, p = 0.0073), and with white matter hyperintensity volume in symptomatic ischemic stroke patients (lead SNP OR 1.07, 95% CI 1.01-1.13, p = 0.016), the direction of association was the same. There was no convincing evidence of association with white matter hyperintensities in population-based studies or with non-small vessel disease cerebrovascular phenotypes.

CONCLUSIONS

Our results indicate an association between common variation in the COL4A2 gene and symptomatic small vessel disease, particularly deep intracerebral hemorrhage. These findings merit replication studies, including in ethnic groups of non-European ancestry.

Abstract W P293: Opportunities For Interventions In Stroke-Dizziness Presentations: A Prospective Single Center Surveillance Study

Objective: Ischemic stroke can be a diagnostic dilemma in presentations of acute dizziness and increased resources will likely be required to reduce instances of misdiagnosis. To inform the potential value of the deployment of increased resources, we sought to describe opportunities for therapeutic interventions from a series of acute dizziness-stroke patients who had diagnostic uncertainty (i.e., only mild or no general neurologic deficits) on presentation.

Methods: Active and passive surveillance methods were used at a tertiary care center to identify acute dizziness patients with nystagmus or imbalance, excluding those with benign paroxysmal positional vertigo, medical causes, or moderate-to-severe neurologic deficits. Stroke was defined as any acute infarction on a clinical or research MRI performed within 14 days of dizziness onset.

Results: From November 21, 2009, to March 29, 2013, we identified 26 patients with acute ischemic stroke presenting with dizziness and either mild or no general neurologic deficits. Infarction volume was small (<1cm3) in 19 (73%), moderate (≥1-<10cm3) in 2 (8%), and large (>10cm3) in 5 (19%). The proportion of cases arriving within 3, 4.5, and 6 hours of symptom onset was 38% (10), 38% (10), and 46% (12). Two cases were treated with thrombolysis. Half of all cases were already prescribed a statin medication at the time of presentation and 42% (11) were already prescribed an antiplatelet or anticoagulant. One patient met clinical eligibility for sub-occipital craniectomy. Three patients were discharged to a skilled nursing facility (1) or acute rehabilitation (2), whereas the majority (22; 85%) were discharged home.

Conclusion: In this single center study which used rigorous surveillance and imaging-based methods to capture cases of acute dizziness-ischemic stroke with only mild or no general neurologic deficits, we found that a minority of patients met time requirements for acute treatments, nearly half were already on secondary prevention medications, and the majority did not require discharge to a skilled nursing facility or acute rehabilitation.

Factors influencing sex differences in poststroke functional outcome

BACKGROUND AND PURPOSE

Our objective was to identify factors that contribute to or modify the sex difference in poststroke functional outcome.

METHODS

Ischemic strokes (n=439) were identified from the Brain Attack Surveillance in Corpus Christi (BASIC) Project (2008-2011). Data were ascertained from interviews (baseline and 90 days post stroke) and medical records. Functional outcome was measured as an average of 22 activities of daily living (ADL)/instrumental ADL items (range, 1-4; higher scores worse function). Tobit regression was used to estimate sex differences and to identify confounding and modifying factors.

RESULTS

Fifty-one percent were women. Median age was 71 (interquartile range, 59-80) years in women and 64 (interquartile range, 56-77) years in men. Median ADL/instrumental ADL score at 90 days was 2.7 (interquartile range, 1.8-3.6) in women and 2.0 (interquartile range, 1.3-3.1) in men (P<0.01); this difference remained after age-adjustment (P<0.001). Factors contributing to higher ADL/instrumental ADL scores in women included prestroke function, marital status, prestroke cognition, nursing home residence, stroke severity, history of stroke/transient ischemic attack, and body mass index; prestroke function was the largest contributor. Stroke severity modified the sex difference in outcome such that differences were apparent for mild to moderate but not severe strokes. After adjustment, women still had significantly worse functional outcome than men.

CONCLUSIONS

These findings yield insight into possible strategies and subgroups to target to reduce the sex disparity in stroke outcome; demographics and prestroke and clinical factors explained only 41% of the sex difference in stroke outcome highlighting the need for future research to identify modifiable factors that contribute to sex differences.

Racial and Ethnic Differences in Mental Distress among Stroke Survivors

OBJECTIVE

African Americans, Hispanics and some Asian subgroups have a higher stroke incidence than non-Hispanic Whites (NHW). Additionally, African Americans and Hispanics have worse stroke outcomes than non-Hispanic Whites. Thus, we explored racial and ethnic differences in mental distress, a known risk factor for post-stroke disability.

METHODS

National Health Interview Survey data from 2000-2010 were used to identify 8,324 community dwelling adults with self-reported stroke. Serious mental distress was identified by the Kessler-6 scale. Logistic regression models assessed racial/ethnic associations with serious mental distress after adjusting for demographics, comorbidities, disability, health care utilization and socioeconomic factors.

RESULTS

Serious mental distress was identified in 9% of stroke survivors. Hispanics (14%) were more likely to have serious mental distress than African Americans (9%), non-Hispanic Whites (9%) and Asians (8%, P = .02). After adjustment, Hispanics (OR = 1.06, 95% CI .76-1.48) and Asians (.84, 95% Cl .37-1.90) had a similar odds of serious mental distress while African Americans had a lower odds of serious mental distress (OR = .61, 95% CI .48-.78) compared with non-Hispanic Whites. Younger age, low levels of education and insurance were important predictors of serious mental distress among Hispanics.

CONCLUSION

Serious mental distress is highly prevalent among US stroke survivors and is more common in Hispanics than NHWs, African Americans and Asians. Further study of the role of mental distress in ethnic differences in post-stroke disability is warranted.

Ischemic stroke subtype and presence of sleep-disordered breathing: the BASIC sleep apnea study

BACKGROUND

Little is known about the prevalence of sleep-disordered breathing (SDB) across ischemic stroke subtypes. Given the important implications for SDB screening, we tested the association between SDB and ischemic stroke subtype in a population-based study.

METHODS

Within the Brain Attack Surveillance in Corpus Christi Project, ischemic stroke patients were offered SDB screening with the ApneaLink Plus (n = 355). A neurologist assigned Trial of the ORG 10172 in Acute Stroke Treatment subtype (with an additional category for nonlacunar infarctions of unknown etiology) using hospital records. Unadjusted and adjusted (demographics, body mass index, National Institutes of Health Stroke Scale, diabetes, history of stroke/transient ischemic attack) logistic and linear regression models were used to test the association between subtype and SDB or apnea-hypopnea index (AHI).

RESULTS

Median age was 65%, and 55% were men; 59% were Mexican American. Median time from stroke onset to SDB screen was 13 days (interquartile range [IQR] 6, 21). Overall, 215 (61%) had SDB (AHI ≥ 10). Median AHI was 13 (IQR 6, 27). Prevalence of SDB by subtype was cardioembolism, 66%; large-artery atherosclerosis, 57%; small-vessel occlusion, 68%; other determined, 50%; undetermined etiology, 58%; and nonlacunar stroke of unknown etiology, 63%. Ischemic stroke subtype was not associated with SDB in unadjusted (P = .72) or adjusted models (P = .91) models. Ischemic stroke subtype was not associated with AHI in unadjusted (P = .41) or adjusted models (P = .62).

CONCLUSIONS

In this population-based stroke surveillance study, ischemic stroke subtype was not associated with the presence or severity of SDB. Sleep-disordered breathing is likely to be present after ischemic stroke, and the subtype should not influence decisions about SDB screening.

Prevalence of pre-stroke sleep apnea risk and short or long sleep duration in a bi-ethnic stroke population

BACKGROUND

The ethnic disparity in ischemic stroke between Mexican Americans (MAs) and non-Hispanic whites (NHWs) may be partly attributable to disparities in sleep and its disorders. We therefore assessed whether pre-stroke sleep apnea symptoms (SA risk) and pre-stroke sleep duration differed between MAs and NHWs.

METHODS

MA and NHW ischemic stroke survivors in the Brain Attack Surveillance in Corpus Christi (BASIC) project reported sleep duration and SA symptoms on the validated Berlin questionnaire, both with respect to their pre-stroke baseline. Log binomial and linear regression models were used to test the unadjusted and adjusted (demographics and vascular risk factors) associations of high-risk Berlin scores and sleep duration with ethnicity.

RESULTS

Among 862 subjects, 549 (63.7%) were MA and 514 (59.6%) had a high risk of pre-stroke SA. The MA and NHW subjects showed no ethnic difference, after adjustment for potential confounders, in pre-stroke SA risk (risk ratio (95% confidence interval (CI)): 1.06 (0.93, 1.20)) or in pre-stroke sleep duration (on average MAs slept 2.0 fewer minutes than NHWs, 95% CI: -18.8, 14.9 min).

CONCLUSIONS

Pre-stroke SA symptoms are highly prevalent, but ethnic differences in SA risk and sleep duration appear unlikely to explain ethnic stroke disparities.

APOE ε variants increase risk of warfarin-related intracerebral hemorrhage

OBJECTIVE

We aimed to assess the effect of APOE ε variants on warfarin-related intracerebral hemorrhage (wICH), evaluated their predictive power, and tested for interaction with warfarin in causing wICH.

METHODS

This was a prospective, 2-stage (discovery and replication), case-control study. wICH was classified as lobar or nonlobar based on the location of the hematoma. Controls were sampled from ambulatory clinics (discovery) and random digit dialing (replication). APOE ε variants were directly genotyped. A case-control design and logistic regression analysis were utilized to test for association between APOE ε and wICH. A case-only design and logistic regression analysis were utilized to test for interaction between APOE ε and warfarin. Receiver operating characteristic curves were implemented to evaluate predictive power.

RESULTS

The discovery stage included 319 wICHs (44% lobar) and 355 controls. APOE ε2 was associated with lobar (odds ratio [OR] 2.46; p < 0.001) and nonlobar wICH (OR 1.67; p = 0.04), whereas ε4 was associated with lobar (OR 2.09; p < 0.001) but not nonlobar wICH (p = 0.35). The replication stage (63 wICHs and 1,030 controls) confirmed the association with ε2 (p = 0.03) and ε4 (p = 0.003) for lobar but not for nonlobar wICH (p > 0.20). Genotyping information on APOE ε variants significantly improved case/control discrimination of lobar wICH (C statistic 0.80). No statistical interaction between warfarin and APOE was found (p > 0.20).

CONCLUSIONS

APOE ε variants constitute strong risk factors for lobar wICH. APOE exerts its effect independently of warfarin, although power limitations render this absence of interaction preliminary. Evaluation of the predictive ability of APOE in cohort studies is warranted.

Loss of the Mexican American survival advantage after ischemic stroke

BACKGROUND AND PURPOSE

Mexican Americans (MAs) were previously found to have lower mortality after ischemic stroke than non-Hispanic whites. We studied mortality trends in a population-based design.

METHODS

Active and passive surveillance were used to find all ischemic stroke cases from January 2000 to December 2011 in Nueces County, TX. Deaths were ascertained from the Texas Department of Health through December 31, 2012. Cumulative 30-day and 1-year mortality adjusted for covariates was estimated using log-binomial models with a linear term for year of stroke onset used to model time trends. Models used data from the entire study period to estimate adjusted mortality among stroke cases in 2000 and 2011 and to calculate projected ethnic differences.

RESULTS

There were 1974 ischemic strokes among non-Hispanic whites and 2439 among MAs. Between 2000 and 2011, model estimated mortality declined among non-Hispanic whites at 30 days (7.6% to 5.6%; P=0.24) and 1 year (20.8% to 15.5%; P=0.02). Among MAs, 30-day model estimated mortality remained stagnant at 5.1% to 5.2% (P=0.92), and a slight decline from 17.4% to 15.3% was observed for 1-year mortality (P=0.26). Although ethnic differences in 30-day (P=0.01) and 1-year (P=0.06) mortality were apparent in 2000, they were not so in 2011 (30-day mortality, P=0.63; 1-year mortality, P=0.92).

CONCLUSIONS

Overall, mortality after ischemic stroke has declined in the past decade, although significant declines were only observed for non-Hispanic whites and not MAs at 1 year. The survival advantage previously documented among MAs vanished by 2011. Renewed stroke prevention and treatment efforts for MAs are needed.

Racial differences in disability after stroke: results from a nationwide study

OBJECTIVE

We sought to characterize racial differences in disability among older stroke survivors.

METHODS

A cross-sectional study of 806 self-reported stroke survivors from the 2011 National Health and Aging Trends Study was performed. Race was based on self-report. Primary outcome was activity limitations (requiring assistance with mobility, self-care, and household activities). Secondary outcome was participation restrictions, which were defined as reductions/absence in valued social activities because of health. Physical capacity was measured by a validated scale (0 low-12 high). Logistic regression was used to estimate average marginal effects of activity limitations and participation restrictions by race before and after adjusting for sociodemographics, comorbidities, and physical and cognitive capacity.

RESULTS

Non-Hispanic black participants had lower physical capacity than non-Hispanic white participants (mean 5.1 vs 6.9, p < 0.01). For most activities, black participants had significantly greater limitations than white participants. These differences persisted after accounting for sociodemographic factors and comorbidities, but largely became nonsignificant after accounting for physical capacity. The only unadjusted racial difference in participation restriction was in religious service attendance (18.2% of white participants vs 28.6% of black participants, p < 0.01).

CONCLUSION

After stroke, black individuals have a greater prevalence of activity limitations than white individuals, largely due to their greater physical capacity limitations. Further understanding of the causes of racial differences in capacity after stroke is needed to reduce activity limitations after stroke and decrease racial disparities.

Influence of hospital-level practices on readmission after ischemic stroke

OBJECTIVE

To inform stroke quality improvement initiatives by determining the relationship between hospital-level stroke practices and readmission after accounting for patient-level factors.

METHODS

Retrospective cohort study of adult patients hospitalized for ischemic stroke (principal ICD-9-CM codes 433.x1, 434.x1, and 436) in 5 states from 2003 to 2009 from State Inpatient Databases. The primary outcome was any unplanned readmission within 30 days. Multilevel logistic regression was used to estimate the association between hospital-level practice patterns of care (diagnostic testing, procedures, intensive care unit, tissue plasminogen activator, and therapeutic modalities) and readmission after adjustment for patient factors and whether individual patients received a given practice.

RESULTS

Thirty-day unplanned readmission occurred in 15.2% of stroke admissions; the median hospital readmission rate was 13.6% (interquartile range 9.8%-18.2%). Of the 25 hospital practice patterns of care analyzed, 3 practices were associated with readmission: hospitals with higher use of occupational therapy and higher proportion of transfers from other hospitals had lower adjusted readmission rates, whereas hospitals with higher use of hospice had higher predicted readmission rates. Readmission rates in lowest vs highest utilizing quintile were as follows: occupational therapy 16.2% (95% confidence interval [CI] 14.5%-18.0%) vs 12.3% (95% CI 11.3%-13.2%); transfers 13.8% (95% CI 13.2%-14.5%) vs 12.5% (95% CI 11.6%-13.5%); and hospice 13.1% (95% CI 12.3%-14.0%) vs 14.8% (95% CI 13.5%-16.1%).

CONCLUSIONS

Hospital practices have a role in stroke readmission that is complex and poorly understood. Further work is needed to identify specific strategies to reduce readmission rates and to ensure that public reporting of readmission rates will not result in adverse unintended consequences.