Clinical Impact of Thrombophilia Screening in Young Adults with Ischemic Stroke.

OBJECTIVE: We evaluated the ability of genetic and serological testing to diagnose clinically relevant thrombophilias in young adults with ischemic stroke. METHODS: We performed a retrospective cohort study of patients aged 18-65 years diagnosed with acute ischemic stroke at a comprehensive stroke center between 2011 and 2015 with laboratory testing for thrombophilia. The primary outcome was any positive thrombophilia screening test. The secondary outcome was a change in clinical management based on thrombophilia testing results. Logistic regression was used to assess whether the prespecified risk factors of age, sex, prior venous thromboembolism, family history of stroke, stroke subtype, and presence of patent foramen ovale were associated with outcomes. RESULTS: Among 196 young ischemic stroke patients, at least 1 positive thrombophilia test was identified in 85 patients (43%; 95% CI, 36%-51%) and 16 (8%; 95% CI, 5%-13%) had a resultant change in management. Among 111 patients with cryptogenic strokes, 49 (44%) had an abnormal thrombophilia test and 9 (8%) had a change in management. After excluding cases of isolated hyperhomocysteinemia or methylenetetrahydrofolate reductase or Factor V Leiden gene mutation heterozygosity, the proportion of patients with an abnormal thrombophilia screen decreased to 24%. Prespecified risk factors were not significantly associated with positive thrombophilia testing or a change in management. CONCLUSIONS: Two-of-five young patients with ischemic stroke who underwent thrombophilia screening at our institution had at least 1 positive test but only one-in-twelve had a resultant change in clinical management. Neither cryptogenic stroke subtype nor other studied clinical factors were associated with a prothrombotic state.

Comparative Risks of Ischemic Stroke in Atrial Flutter versus Atrial Fibrillation.

INTRODUCTION: The aim of this study was to compare the risk of ischemic stroke in patients who have atrial fibrillation and patients who have atrial flutter. METHODS: Using inpatient and outpatient Medicare claims data from 2008 to 2014 for a 5% sample of all beneficiaries 66 years of age or older, we identified patients diagnosed with atrial fibrillation and those diagnosed with atrial flutter. The primary outcome was ischemic stroke. In the primary analysis, patients with atrial flutter were censored upon converting to fibrillation; in a secondary analysis, they were not. Survival statistics were used to compare incidence of stroke in patients with flutter and patients with fibrillation. Cox proportional hazards analysis was used to compare the associations of flutter and fibrillation with ischemic stroke after adjustment for demographics and risk factors. RESULTS: We identified 14,953 patients with flutter and 318,138 with fibrillation. During a mean follow-up period of 2.8 (±2.3) years, we identified 18,900 ischemic strokes. The annual incidence of ischemic stroke in patients with flutter was 1.38% (95% confidence interval [CI] 1.22%-1.57%) compared with 2.02% (95% CI 1.99%-2.05%) in patients with fibrillation. After adjustment for demographics and stroke risk factors, flutter was associated with a lower risk of stroke compared with fibrillation (hazard ratio .69; 95% CI .60-.79, P < .05). Within 1 year, 65.7% (95% CI 64.9%-66.4%) of patients with flutter converted to fibrillation but remained at a lower risk of ischemic stroke (hazard ratio .85; 95% CI .78-.92). CONCLUSIONS: Patients with atrial flutter faced a lower risk of ischemic stroke than patients with atrial fibrillation.

County-Level Socio-Environmental Factors Associated With Stroke Mortality in the United States: A Cross-Sectional Study.

We used machine learning methods to explore sociodemographic and environmental determinants of health (SEDH) associated with county-level stroke mortality in the USA. We conducted a cross-sectional analysis of individuals aged ≥15 years who died from all stroke subtypes between 2016 and 2020. We analyzed 54 county-level SEDH possibly associated with age-adjusted stroke mortality rates/100,000 people. Classification and Regression Tree (CART) was used to identify specific county-level clusters associated with stroke mortality. Variable importance was assessed using Random Forest analysis. A total of 501,391 decedents from 2397 counties were included. CART identified 10 clusters, with 77.5% relative increase in stroke mortality rates across the spectrum (28.5 vs 50.7 per 100,000 persons). CART identified 8 SEDH to guide the classification of the county clusters. Including, annual Median Household Income ($), live births with Low Birthweight (%), current adult Smokers (%), adults reporting Severe Housing Problems (%), adequate Access to Exercise (%), adults reporting Physical Inactivity (%), adults with diagnosed Diabetes (%), and adults reporting Excessive Drinking (%). In conclusion, SEDH exposures have a complex relationship with stroke. Machine learning approaches can help deconstruct this relationship and demonstrate associations that allow improved understanding of the socio-environmental drivers of stroke and development of targeted interventions.

Basilar artery curvature is associated with migraine with aura in the Northern Manhattan Study.

INTRODUCTION: Genetic and imaging studies demonstrate a link between vascular morphology and migraine with aura (MA). We examined the relationship between basilar artery (BA) curvature and MA in a population-based cohort of stroke-free participants. METHODS: This cross-sectional study included participants from the MRI substudy of the Northern Manhattan Study. Participants had structured migraine assessments at enrollment and underwent brain MR angiography. BA curvature was defined as the sum of the total BA horizontal deviation from midline at the distal tip, mid-pons, and vertebrobasilar junction, and was the primary independent variable in logistic regression analyses. BA measurements were obtained blinded to migraine status. We compared groups of all migraine vs no migraine, migraine without aura (MwoA) vs no migraine, and MA vs no migraine. RESULTS: Of 880 participants, 146 had MwoA and 32 had MA. Average BA curvatures were 15.2 ± 8.9 mm in non-migraineurs, 15.8 ± 9.3 mm in MwoA, and 18.5 ± 11.4 mm in MA. In an adjusted model, greater BA curvature was associated with MA (OR 1.042 per mm, 95% CI 1.006-1.080) but not with MwoA (OR 1.014 per mm, 95% CI 0.993-1.035), when compared to non-migraineurs. CONCLUSIONS: Greater BA curvature was associated with MA. Given aura typically originates from the occipital cortex, understanding the physiopathology of this association may provide clues to migraine's underlying mechanisms and relationship with stroke.