Systematic Review of Sex Differences in Ischemic Strokes Among Young Adults: Are Young Women Disproportionately at Risk?

BACKGROUND AND PURPOSE: Recent evidence suggests that young women (18-45 years) may be at higher risk of ischemic strokes than men of the same age. The goal of this systematic review is to reconcile and synthesize existing evidence of sex differences among young adults with ischemic strokes. METHODS: We searched PubMed from January 2008 to July 2021 for relevant articles and reviews and consulted their references. We included original studies that (1) were population based and (2) reported stroke incidence by sex or sex-specific incidence rate ratios of young adults ≤45 years. We excluded studies that (1) omitted measurements of error for incidence rates or incidence rate ratios, (2) omitted age adjustment, and (3) were not in English. Statistical synthesis was performed to estimate sex difference by age group (≤35, 35-45, and ≤45) and stroke type. RESULTS: We found 19 studies that reported on sex-specific stroke incidence among young adults, including 3 that reported on overlapping data. Nine studies did not find a statistically significant sex difference among young adults ≤45 years. Three studies found higher rates of ischemic stroke among men among young adults ≥30 to 35 years. Four studies found more women with ischemic strokes among young adults ≤35 years. Overall, in young adults ≤35 years, the estimated effect size favored more ischemic strokes in women (incidence rate ratio, 1.44 [1.18-1.76], I2=82%) and a nonsignificant sex difference in young adults 35 to 45 years (incidence rate ratio, 1.08 [0.85-1.38], I2=95%). CONCLUSIONS: Overall, there were 44% more women ≤35 years with ischemic strokes than men. This gap narrows in young adults, 35 to 45 years, and there is conflicting evidence whether more men or women have ischemic strokes in the 35 to 45 age group.

Large Vessel Occlusion Prediction in the Emergency Department with National Institutes of Health Stroke Scale Components: A Machine Learning Approach.

OBJECTIVE: To determine the feasibility of using a machine learning algorithm to screen for large vessel occlusions (LVO) in the Emergency Department (ED). MATERIALS AND METHODS: A retrospective cohort of consecutive ED stroke alerts at a large comprehensive stroke center was analyzed. The primary outcome was diagnosis of LVO at discharge. Components of the National Institutes of Health Stroke Scale (NIHSS) were used in various clinical methods and machine learning algorithms to predict LVO, and the results were compared with the baseline method (aggregate NIHSS score with threshold of 6). The Area-Under-Curve (AUC) was used to measure the overall performance of the models. Bootstrapping (n = 1000) was applied for the statistical analysis. RESULTS: Of 1133 total patients, 67 were diagnosed with LVO. A Gaussian Process (GP) algorithm significantly outperformed other methods including the baseline methods. AUC score for the GP algorithm was 0.874 ± 0.025, compared with the simple aggregate NIHSS score, which had an AUC score of 0.819 ± 0.024. A dual-stage GP algorithm is proposed, which offers flexible threshold settings for different patient populations, and achieved an overall sensitivity of 0.903 and specificity of 0.626, in which sensitivity of 0.99 was achieved for high-risk patients (defined as initial NIHSS score > 6). CONCLUSION: Machine learning using a Gaussian Process algorithm outperformed a clinical cutoff using the aggregate NIHSS score for LVO diagnosis. Future studies would be beneficial in exploring prospective interventions developed using machine learning in screening for LVOs in the emergent setting.

Young Women Had More Strokes Than Young Men in a Large, United States Claims Sample.

BACKGROUND AND PURPOSE: Cardiovascular risk factors, which are overall more prevalent in men, are considered the major risk factors for strokes among young adults. However, recent European data found the incidence of strokes to be higher in young women. Using a large US claims sample, we examined sex differences in the index stroke rate of young adults. METHODS: We performed a retrospective cohort study of enrollees in a 10% random sample of PharMetrics, a nationally representative claims database of insured Americans from 2001 to 2014. Outcomes were index ischemic stroke events, based on inpatient admissions using International Classification of Diseases-Ninth Revision codes. The index stroke rate was estimated from Poisson rate models with time varying covariates for 2-year periods, stratified by sex and age groups. RESULTS: We identified 20 554 index strokes (50.4% women; mean age 63) including 5198 in young adults ages 15 to 54. There was no difference by sex in the index stroke rate in the extremes of age groups 15 to 24 and ≥75 years old. However, in the 25 to 34 and 35 to 44 year age groups, more women had strokes than men (incidence rate ratio: men:women, 0.70 [95% CI, 0.57-0.86]; 0.87 [95% CI, 0.78-0.98], respectively). In contrast, in the 45 to 54, 55 to 64, and 65 to 74 year age groups, more men had strokes (incidence rate ratio, 1.25 [95% CI, 1.16-1.33]; 1.41 [95% CI, 1.18-1.34]; 1.18 [95% CI, 1.12-125], respectively). CONCLUSIONS: More young women than men have strokes, suggesting possible importance of sex-mediated etiologies of stroke. Understanding these drivers is critical to stroke treatment and prevention efforts in young adults.

Temporal Trends in Stroke Incidence Over Time by Sex and Age in the GCNKSS.

Background and Purpose- Sex differences in stroke incidence over time were previously reported from the GCNKSS (Greater Cincinnati/Northern Kentucky Stroke Study). We aimed to determine whether these differences continued through 2015 and whether they were driven by particular age groups. Methods- Within the GCNKSS population of 1.3 million, incident (first ever) strokes among residents ≥20 years of age were ascertained at all local hospitals during 5 periods: July 1993 to June 1994 and calendar years 1999, 2005, 2010, and 2015. Out-of-hospital cases were sampled. Sex-specific incidence rates per 100 000 were adjusted for age and race and standardized to the 2010 US Census. Trends over time by sex were compared (overall and age stratified). Sex-specific case fatality rates were also reported. Bonferroni corrections were applied for multiple comparisons. Results- Over the 5 study periods, there were 9733 incident strokes (56.3% women). For women, there were 229 (95% CI, 215-242) per 100 000 incident strokes in 1993/1994 and 174 (95% CI, 163-185) in 2015 (P<0.05), compared with 282 (95% CI, 263-301) in 1993/1994 to 211 (95% CI, 198-225) in 2015 (P<0.05) in men. Incidence rates decreased between the first and last study periods in both sexes for IS but not for intracerebral hemorrhage or subarachnoid hemorrhage. Significant decreases in stroke incidence occurred between the first and last study periods for both sexes in the 65- to 84-year age group and men only in the ≥85-year age group; stroke incidence increased for men only in the 20- to 44-year age group. Conclusions- Overall stroke incidence decreased from the early 1990s to 2015 for both sexes. Future studies should continue close surveillance of sex differences in the 20- to 44-year and ≥85-year age groups, and future stroke prevention strategies should target strokes in the young- and middle-age groups, as well as intracerebral hemorrhage.

A Clinical Paradigm for Classifying Neurologic Symptoms to Screen for Emergent Large Vessel Occlusions.

BACKGROUND: With newly-extended treatment windows for endovascular therapy in emergent large vessel occlusions, it is increasingly important to identify thrombectomy-eligible patients without overwhelming resources dedicated to acute stroke care. We devised a simple paradigm to classify patient's presenting neurologic symptoms to screen for large vessel occlusions. METHODS: We reviewed the presenting symptoms, imaging findings, and final diagnoses of consecutive emergency department stroke alert cases. Patients were classified based on their neurologic exams as focal objective, focal subjective, or nonfocal. Outcomes of final diagnoses of acute ischemic stroke and large vessel occlusions were compared across groups. Comparisons were made to other large vessel occlusion prediction scales. RESULTS: Of 521 patients, 342 (65.6%) were categorized as focal objective, 142 (27.2%) as focal subjective, and 37 (7.1%) as nonfocal. Ischemic stroke and large vessel occlusions were diagnosed in 114 (21.9%) and 27 (5.2%) of patients, respectively. Classification as focal objective significantly predicted stroke (odds ratio 3.77; 95% confidence interval 2.17-6.55) and captured all large vessel occlusions (P = .0001). The focal objective categorization was the only tool which achieved 100% sensitivity for large vessel occlusions (with a specificity of 36%) compared to other large vessel occlusion prediction tools. CONCLUSIONS: Patients who presented as stroke alerts without focal neurologic symptoms were unlikely to have large vessel occlusions. With high sensitivity, classifying patients' neurologic exams into focal objective versus subjective or nonfocal categories may serve as a useful tool to screen for large vessel occlusions and prevent unnecessary emergent workup in patients unlikely to be endovascular candidates.

Cost-Effectiveness of Patent Foramen Ovale Closure Versus Medical Therapy for Secondary Stroke Prevention.

BACKGROUND AND PURPOSE: Percutaneous transcatheter closure of patent foramen ovale (PFO closure) plus antiplatelet therapy has been shown to reduce the risk of recurrent stroke compared with medical therapy alone in carefully selected patients after cryptogenic stroke presumed to be from paradoxical embolism. Our objective was to determine the cost-effectiveness of PFO closure after cryptogenic stroke compared with conservative medical management from a US healthcare payer perspective. METHODS: A decision analytic Markov model estimated the 15-year cost and outcomes associated with the additional benefit of PFO closure compared with medical management alone. Model inputs were obtained from published literature, national databases, and a meta-analysis of 5 published randomized clinical trials on PFO closure. Health outcomes were measured in quality-adjusted life years (QALY). Cost-effectiveness used the incremental cost per QALY gained, whereas the net monetary benefit assumed a willingness to pay of $150 000/QALY. One-way and probabilistic sensitivity analyses estimated the uncertainty of model results. RESULTS: At 15 years, PFO closure compared with medical therapy alone improved QALY by 0.33 at a cost saving of $3568, representing an incremental net monetary benefit of $52 761 (95% interval -$8284 to $158 910). When the meta-analysis hazard ratio for stroke was increased to the 95% interval's upper bound of 0.77, one-way sensitivity analyses suggested that PFO closure's cost-effectiveness was $458 558 per additional QALY. Probabilistic sensitivity analysis suggested cost-effectiveness in 90% of simulation runs. CONCLUSIONS: PFO closure for cryptogenic strokes in the right setting is cost-effective, producing benefit in QALYs gained and potential cost savings. However, patient selection remains vitally important as marginal declines in treatment effectiveness can dramatically affect cost-effectiveness.

Index Case of Cutaneous Follicular Mycosis Fungoides With Central Nervous System Involvement and Review of Literature.

Central nervous system involvement by mycosis fungoides (MF) is rare and is usually seen in advanced stages of the disease. We describe a patient with early-stage follicular MF who presented with changes in mental status. Despite an initial diagnosis of vasculitis based on clinical and brain biopsy results, the postmortem examination revealed extensive infiltration of MF cells throughout the brain with leptomeningeal involvement. This case in addition to the accompanied review of literature illustrates the importance of the awareness of central nervous system involvement by MF and highlights the need for an urgent neurologic evaluation in patients with a history of MF now presenting with neurologic signs or symptoms.

The Addition of Endovascular Intervention for Dural Venous Sinus Thrombosis: Single-Center Experience and Review of Literature.

BACKGROUND: Dural venous sinus thrombosis (DVST) is a cause of infarction and intracranial hemorrhage (ICH) that can lead to significant morbidity. Endovascular therapy has emerged as an adjunctive therapy in select cases but has been associated with increased hemorrhagic complications. We present our experience with a large single-center cohort of DVST cases treated with current-generation thrombectomy devices. MATERIALS AND METHODS: In this retrospective cohort study, a chart review was performed to compare presentations and outcomes of patients treated with anticoagulation alone with those treated with additional interventional therapy, using the modified Rankin Scale (mRS) score at discharge and at 90 days' follow-up. RESULTS: A total of 66 patients were included; 37 were treated with anticoagulation alone, and 29 underwent additional interventional therapy. Patients presenting with ICH or infarction had a significantly greater likelihood of disability at the time of discharge (odds ratio [OR] of 64.5 and 45.8, respectively; P < .0001) and at 90 days (OR of 28.4 and 22.8, respectively; P < .0001). Patients presenting with ICH or infarction were more likely to be selected for endovascular therapy (P < .05). Endovascular therapy was typically performed within 24 hours of admission; 9 patients (31%) had post-treatment hemorrhage, with 2 being (6.9%) symptomatic. There were fewer patients with slight disability (mRS score ≤1) in the endovascular group compared with the anticoagulation group at discharge (P = .05), but outcomes were not significantly different at 90 days (P = .19). CONCLUSIONS: Despite a higher rate of ICH or infarction at presentation in the endovascular group and an increased risk of postprocedural ICH, both treatment groups had similarly good functional outcomes at 90 days.