Gender differences in carotid imaging and revascularization following stroke

Service delivery in acute ischemic stroke patients: Does sex matter?

BACKGROUND AND PURPOSE

Women with acute ischemic stroke (AIS) are older and have greater preexisting handicap than men. Given that these factors do not fully explain their poorer long-term outcomes, we sought to investigate potential sex differences in the delivery of acute stroke care in a large cohort of consecutive AIS patients.

METHODS

We analyzed all patients from ASTRAL (Acute Stroke Registry and Analysis of Lausanne) from March 2003 to December 2019. Multivariable analyses were performed on acute time metrics, revascularization therapies, ancillary examinations for stroke workup, subacute symptomatic carotid artery revascularization, frequency of change in goals of care (palliative care), and length of hospital stay.

RESULTS

Of the 5347 analyzed patients, 45% were biologically female and the median age was 74.6 years. After multiple adjustments, female sex was significantly associated with higher onset-to-door (adjusted hazard ratio [aHR] = 1.09, 95% confidence interval [CI] = 1.04-1.14) and door-to-endovascular-puncture intervals (aHR = 1.15, 95% CI = 1.05-1.25). Women underwent numerically fewer diagnostic examinations (adjusted odds ratio [aOR] = 0.94, 95% CI = 0.85-1.04) and fewer subacute carotid revascularizations (aOR = 0.69, 95% CI = 0.33-1.18), and had longer hospital stays (aHR = 1.03, 95% CI = 0.99-1.07), but these differences were not statistically significant. We found no differences in the rates of acute revascularization treatments, or in the frequency of change of goals of treatments.

CONCLUSIONS

This retrospective analysis of a large, consecutive AIS cohort suggests that female sex is associated with unfavorable pre- and in-hospital time metrics, such as a longer onset-to-door and door-to-endovascular-puncture intervals. Such indicators of less effective stroke care delivery may contribute to the poorer long-term functional outcomes in female patients and require further attention.

Sex Differences in Carotid Atherosclerosis: A Systematic Review and Meta-Analysis

BACKGROUND

Over the last decades, several individual studies on sex differences in carotid atherosclerosis have been performed covering a wide range of plaque characteristics and including different populations. This systematic review and meta-analysis aims to summarize previously reported results on sex differences in carotid atherosclerosis and present a roadmap explaining next steps needed for implementing this knowledge in clinical practice.

METHODS

We systematically searched PubMed, Embase, Web of Science, Cochrane Central, and Google Scholar for eligible studies including both male and female participants reporting prevalence of imaging characteristics of carotid atherosclerosis and meta-analyzed these studies. Studies had to report at least the following: (1) calcifications; (2) lipid-rich necrotic core; (3) intraplaque hemorrhage; (4) thin-or-ruptured fibrous cap; (5) plaque ulceration; (6) degree of stenosis; (7) plaque size; or (8) plaque inflammation. We prespecified which imaging modalities had to be used per plaque characteristic and excluded ultrasonography.

RESULTS

We included 42 articles in our meta-analyses (ranging from 2 through 23 articles per plaque characteristic). Men had more frequently a larger plaque compared to women and, moreover, had more often plaques with calcifications (odds ratio=1.57 [95% CI, 1.23-2.02]), lipid-rich necrotic core (odds ratio=1.87 [95% CI, 1.36-2.57]), and intraplaque hemorrhage (odds ratio=2.52 [95% CI, 1.74-3.66]), or an ulcerated plaque (1.81 [95% CI, 1.30-2.51]). Furthermore, we found more pronounced sex differences for lipid-rich necrotic core in symptomatic opposed to asymptomatic participants.

CONCLUSIONS

In this systematic review and meta-analysis, we demonstrate convincing evidence for sex differences in carotid atherosclerosis. All kinds of plaque features-plaque size, composition, and morphology-were more common or larger in men compared to women. Our results highlight that sex is an important variable to include in both study design and clinical-decision making. Further investigation of sex-specific stroke risks with regard to plaque composition is warranted.

Importance of sex and gender in ischaemic stroke and carotid atherosclerotic disease

Stroke is a leading cause of death and disability worldwide. Women are disproportionately affected by stroke, exhibiting higher mortality and disability rates post-stroke than men. Clinical stroke research has historically included mostly men and studies were not properly designed to perform sex- and gender-based analyses, leading to under-appreciation of differences between men and women in stroke presentation, outcomes, and response to treatment. Reasons for these differences are likely multifactorial; some are due to gender-related factors (i.e. decreased social support, lack of stroke awareness), yet others result from biological differences between sexes. Unlike men, women often present with 'atypical' stroke symptoms. Lack of awareness of 'atypical' presentation has led to delays in hospital arrival, diagnosis, and treatment of women. Differences also extend to carotid atherosclerotic disease, a cause of stroke, where plaques isolated from women are undeniably different in morphology/composition compared to men. As a result, women may require different treatment than men, as evidenced by the fact that they derive less benefit from carotid revascularization than men but more benefit from medical management. Despite this, women are less likely than men to receive medical therapy for cardiovascular risk factor management. This review focuses on the importance of sex and gender in ischaemic stroke and carotid atherosclerotic disease, summarizing the current evidence with respect to (i) stroke incidence, mortality, awareness, and outcomes, (ii) carotid plaque prevalence, morphology and composition, and gene connectivity, (iii) the role of sex hormones and sex chromosomes in atherosclerosis and ischaemic stroke risk, and (iv) carotid disease management.

Gender, racial and ethnic disparities in index hospitalization operations for symptomatic carotid stenosis in Texas hospitals

BACKGROUND

Recent literature and societal recommendations support early revascularization of symptomatic carotid patients over the traditional six-week period. Nonetheless, the timing of these interventions can vary widely among populations. The goal of this study is to identify any factors influencing carotid revascularization during the index hospitalization for patients with symptomatic disease.

METHODS

The Texas Department of State Health Services database was queried to identify all patients > 45 years old admitted to nonfederal Texas Hospitals between 2009 to 2013 with an admission diagnosis of carotid artery stenosis and either transient ischemic attack (TIA), cerebrovascular accident (CVA), or amaurosis fugax. Diagnoses codes and demographic data were also used to adjust for clinical, social, and demographic factors (including area of residence and treatment). Descriptive statistics and multivariable logistic regression were used to identify significant factors for index admission revascularization.

RESULTS

A total of 29,046 symptomatic patients were identified among the 153,484 patients who had an eligible admission diagnosis. This included 16,244 (55.9%) males and 12,802 (44.1%) females. Only 4,594 (15.8%) patients were revascularized during the index hospitalization. The majority of these patients presented with amaurosis (OR 5.58; 95% CI 4.84-6.44) instead of CVAs (OR 0.48; 95% CI 0.45-0.51) or TIAs . Adjusting for hospital volume, insurance coverage, residence, and other clinical factors, rates of index admission carotid intervention remained significantly lower for women (OR 0.85; 95% CI 0.79-0.91), persons categorized as black (OR 0.60; 95% CI 0.53-0.69), and persons categorized as Hispanic (OR 0.77; 95% CI 0.70-0.86).

CONCLUSIONS

Gender, race and ethnicity appear to correlate with rates of carotid intervention at index hospitalization despite thorough risk adjustment for clinical, social and demographic factors. Efforts should be directed towards reducing these disparities.

Differences in Diagnostic Evaluation in Women and Men After Acute Ischemic Stroke

Background

Sex differences have been found in stroke risk factors, incidence, treatment, and outcomes. There are conflicting data on whether diagnostic evaluation for stroke may differ between men and women.

Methods and Results

We performed a retrospective cohort study using inpatient and outpatient claims between 2008 and 2016 from a nationally representative 5% sample of Medicare beneficiaries. We included patients ≥65 years old and hospitalized with ischemic stroke, defined by International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) and ICD‐10‐CM diagnosis codes. Logistic regression was used to determine the association between female sex and the odds of diagnostic testing and specialist evaluation, adjusted for age, race, and number of Charlson comorbidities. Among 78 822 patients with acute ischemic stroke, 58.3% (95% CI, 57.9–58.6%) were women. Female sex was associated with decreased odds of intracranial vessel imaging (odds ratio [OR]: 0.94; 95% CI, 0.91–0.97), extracranial vessel imaging (OR: 0.89; 95% CI, 0.86–0.92), heart‐rhythm monitoring (OR: 0.92; 95% CI, 0.87–0.98), echocardiography (OR: 0.92; 95% CI, 0.89–0.95), evaluation by a neurologist (OR: 0.94; 95% CI, 0.91–0.97), and evaluation by a vascular neurologist (OR: 0.94; 95% CI, 0.90–0.97), after adjustment for age, race, and comorbidities. These findings were unchanged in separate sensitivity analyses excluding patients who died during the index hospitalization or were discharged to hospice and excluding patients with atrial fibrillation diagnosed before their index stroke.

Conclusions

In a nationally representative cohort of Medicare beneficiaries, we found that women with acute ischemic stroke were less likely to be evaluated by stroke specialists and less likely to undergo standard diagnostic testing compared with men.

Sex differences in the evaluation and treatment of acute ischaemic stroke

With the greater availability of treatments for acute ischaemic stroke, including advances in endovascular therapy, personalised assessment of patients before treatment is more important than ever. Women have a higher lifetime risk of stroke; therefore, reducing potential sex differences in the acute stroke setting is crucial for the provision of equitable and fast treatment. Evidence indicates sex differences in prevalence and types of non-traditional stroke symptoms or signs, prevalence of stroke mimics, and door-to-imaging times, but no substantial differences in use of emergency medical services, stroke knowledge, eligibility for or access to thrombolysis or thrombectomy, or outcomes after either therapy. Women presenting with stroke mimics or non-traditional stroke symptoms can be misdiagnosed, which can lead to inappropriate triage, and acute treatment delays. It is essential for health-care providers to recognise possible sex differences in stroke symptoms, signs, and mimics. Future studies focused on confounders that affect treatment and outcomes, such as age and pre-stroke function, are also needed.

Is carotid imaging underused in patients with transient ischemic attack or ischemic stroke? A Swedish Stroke Register (Riksstroke) study

BACKGROUND AND AIM

Carotid artery stenosis is one of the major causes of transient ischemic attack (TIA) and acute ischemic stroke (IS), and carotid surgery and stenting are used to reduce the risk of ipsilateral IS. However, the adherence to the recommendation of carotid imaging in clinical practice has not been well studied. We analyzed proportions of carotid imaging and determinants for its non-use in patients with TIA and IS with respect to baseline demographics, risk factors, hospital characteristics, and geographical region.

PATIENTS AND METHODS

Hospital-based data on TIA and IS events, registered from July 2011 to June 2013, were obtained from the Swedish Stroke Register (Riksstroke). Carotid imaging diagnostics included carotid Doppler ultrasound and computed tomography angiography.

RESULTS

Carotid imaging was performed in 70% (10 545/15 021) of patients with TIA and 54% (23 772/44 075) of patients with IS. The most significant independent determinants for not undergoing carotid imaging were, in patients with TIA: age ≥85 year (odds ratio (OR), 7.3; 95% confidence interval (CI), 6.4-8.4) and a history of stroke (OR, 2.3; 95% CI, 2.1-2.5); and in patients with IS: age ≥85 year (OR, 9.8; 95% CI, 9.0-10.6), age 75-84 year (OR, 2.5; 95% CI, 2.3-2.7), and reduced level of consciousness at admission (OR, 3.4; 95% CI, 3.1-3.6). Care at a University hospital and in a stroke unit increased the likelihood of carotid imaging. There were substantial regional variations regarding proportions of carotid imaging.

CONCLUSION

Carotid imaging appears to be underused in patients with TIA and IS. Opportunities of secondary stroke prevention with carotid interventions are likely missed.

Sex Differences in the Presentation, Care, and Outcomes of Transient Ischemic Attack: Results From the Ontario Stroke Registry

BACKGROUND AND PURPOSE

Little is known about whether sex differences exist in the presentation, management, and outcomes of transient ischemic attack.

METHODS

We conducted a cohort study of 5991 consecutive patients with transient ischemic attack admitted to 11 stroke centers in Ontario, Canada, between July 1, 2003, and March 31, 2008 and compared presenting symptoms, processes of care, and outcomes in women and men. We used linkages to administrative databases to evaluate mortality and recurrent vascular events within 30 days and 1 year of the initial presentation, with multivariable analyses to assess whether sex differences persisted after adjustment for age and comorbid conditions.

RESULTS

The most common presenting symptoms for both sexes were weakness, speech impairment, and sensory deficit, with headache being slightly more frequent in women. Women were less likely than men to undergo carotid imaging, carotid endarterectomy, or receive lipid-lowering therapy. One-year mortality was slightly lower in women than in men (adjusted hazard ratio, 0.77; 95% confidence interval, 0.63-0.94).

CONCLUSIONS

We found only minor sex differences in the presentation and management of transient ischemic attack, suggesting that current public awareness campaigns focusing on classic warning signs are appropriate for both women and men. Future work should focus on evaluating whether lower rates of carotid imaging, endarterectomy, and lipid-lowering therapy in women reflect undertreatment of women or are appropriate based on patient eligibility.

Sex differences in revascularization interventions after acute ischemic stroke

BACKGROUND

Studies suggest that women are less likely than men to receive intravenous (IV) tissue plasminogen activator (tPA) for acute ischemic stroke (AIS). Relatively little is known about whether this sex disparity in AIS management extends beyond IV tPA use, reflects national practice patterns, or is changing.

METHODS

Data from the Nationwide Inpatient Sample from 1997 to 2006 were used to identify adults (≥18 years of age) who were discharged with a primary diagnosis of AIS (n = 4,453,207) in the United States. Of 605,960 individuals admitted to 1056 hospitals that performed reperfusion/revascularization procedures, sex-specific rates of cerebrovascular reperfusion (e.g., IV tPA, intra-arterial therapy, angioplasty, stent, or carotid endarterectomy [CEA]), and cardiac reperfusion (e.g., catheterization, angioplasty, stent, or bypass graft) were determined before and after adjustment for sociodemographic, clinical, and hospital factors.

RESULTS

Men were more likely than women to receive IV tPA (prevalence ratio [PR] 1.37, 95% confidence interval [CI] 1.32-1.42), catheter angiography (PR 1.36, 95% CI 1.33-1.38), intracranial or extracranial angioplasty/stent (PR 1.73, 95% CI 1.49-2.01), CEA (PR 1.79, 95% CI 1.72-1.86), or any cardiac reperfusion therapy (PR 1.62, 95% CI 1.53-1.71). Multivariable adjustment slightly attenuated the sex disparity. Use of all procedures except CEA rose from 1997 to 2006 in both sexes, but IV tPA use increased at a higher rate for women (compared to men); by 2006, there was no sex difference.

CONCLUSIONS

Over the last decade, women hospitalized for AIS in the United States were less likely than men to receive cerebrovascular and cardiac reperfusion therapies. However, the IV tPA treatment sex disparity may have been eliminated.

Lower use of carotid artery imaging at minority-serving hospitals

OBJECTIVE

We determined whether site of care explains a previously identified racial disparity in carotid artery imaging.

METHODS

In this retrospective cohort study, data were obtained from a chart review of veterans hospitalized with ischemic stroke at 127 Veterans Administration hospitals in 2007. Extensive exclusion criteria were applied to obtain a sample who should have received carotid artery imaging. Minority-serving hospitals were defined as the top 10% of hospitals ranked by the proportion of stroke patients who were black. Population level multivariate logistic regression models with adjustment for correlation of patients in hospitals were used to calculate predictive probabilities of carotid artery imaging by race and minority-service hospital status. Bootstrapping was used to obtain 95% confidence intervals (CIs).

RESULTS

The sample consisted of 1,534 white patients and 628 black patients. Nearly 40% of all black patients were admitted to 1 of 13 minority-serving hospitals. No racial disparity in receipt of carotid artery imaging was detected within nonminority serving hospitals. However, the predicted probability of receiving carotid artery imaging for white patients at nonminority-serving hospitals (89.7%, 95% CI [87.3%, 92.1%]) was significantly higher than both white patients (78.0% [68.3%, 87.8%] and black patients (70.5% [59.3%, 81.6%]) at minority-serving hospitals.

CONCLUSIONS

Underuse of carotid artery imaging occurred most often among patients hospitalized at minority-serving hospitals. Further work is required to explore why site of care is a mechanism for racial disparities in this clinically important diagnostic test.

The gender gap in stroke: a meta-analysis

Several studies have indicated that gender differences might exist in stroke.

OBJECTIVES AND METHODS

Our goal was to perform a comprehensive meta-analysis in order to evaluate and quantify stroke gender disparities through a systematic search of relevant articles published up to October 2009 and addressing gender related differences in ischemic stroke risk factors, stroke subtype and severity, diagnostic tests, and acute phase and secondary prevention treatments.

RESULTS

Forty-five articles were included in the analysis, representing a total of 673,935 patients. Women were globally older than men (+5.2 years) and suffered more hypertension (P = 0.017) and atrial fibrillation (P < 0.001), although they were less likely to drink alcohol (P < 0.001), smoke cigarettes (P < 0.001), present hyperlipidemia (P = 0.033) or diabetes (P = 0.003) than men. Baseline stroke severity was not different between genders. Women suffered more cardioembolic strokes, while men had more atherothrombotic strokes. Moreover, women were less likely to receive stroke-related treatments, such as antiplatelets (P < 0.001), statins (P < 0.001), and tPA (P < 0.001) than men. Although meta-regression did not identify age or stroke etiology as sources of heterogeneity, caution should be taken as that analysis was possible only for gender differences in secondary prevention with antiplatelets because of limited data for other end points.

CONCLUSIONS

Gender differences have been identified on the risk factors profile and diagnostic and therapeutic management of patients with ischemic stroke. Active measures should thus be taken to avoid bias in clinical practice.

Sexual dimorphism in ischemic stroke: lessons from the laboratory

Ischemic stroke is emerging as a major health problem for elderly women. Women have lower stroke incidence than men until an advanced age, when the epidemiology of ischemic stroke shifts and incidence rises dramatically in women. Experimental models of rodent stroke have replicated this clinical epidemiology, with exacerbated injury in older compared with young female rodents. Many of the detrimental effects of aging on ischemic stroke outcome in females can be replicated by ovariectomy, suggesting that hormones such as estrogen play a neuroprotective role. However, emerging data suggest that the molecular mechanisms leading to ischemic cell death differ in the two sexes, and these effects may be independent of circulating hormone levels. This article highlights recent clinical and experimental literature on sex differences in stroke outcomes and mechanisms.

Declining stroke and vascular event recurrence rates in secondary prevention trials over the past 50 years and consequences for current trial design

BACKGROUND

It is widely supposed, but not well-demonstrated, that cumulative advances in standard care have reduced recurrent stroke and cardiovascular events in secondary prevention trials.

METHODS AND RESULTS

Systematic search identified all randomized, controlled trials of medical secondary stroke prevention therapies published from 1960 to 2009. Randomized, controlled trials narrowly focused on single stroke mechanisms, including atrial fibrillation, cervical carotid stenosis, and intracranial stenosis, were excluded. From control arms of individual trials, we extracted data for baseline characteristics and annual event rates for recurrent stroke, fatal stroke, and major vascular events and analyzed trends over time. Fifty-nine randomized controlled trials were identified, enrolling 66 157 patients in control arms. Over the 5 decade periods, annual event rates declined, per decade, for recurrent stroke by 0.996% (P=0.001), fatal stroke by 0.282% (P=0.003), and major vascular events by 1.331% (P=0.001). Multiple regression analyses identified increasing antithrombotic use and lower blood pressures as major contributors to the decline in recurrent stroke. For recurrent stroke, annual rates fell from 8.71% in trials launched in the 1960s to 6.10% in the 1970s, 5.41% in the 1980s, 4.04% in the 1990s, and 4.98% in the 2000s. The sample size required for a trial to have adequate power to detect a 20% reduction in recurrent stroke increased 2.2-fold during this period.

CONCLUSIONS

Recurrent stroke and vascular event rates have declined substantially over the last 5 decades, with improved blood pressure control and more frequent use of antiplatelet therapy as the leading causes. Considerably larger sample sizes are now needed to demonstrate incremental improvements in medical secondary prevention.

Gender differences in stroke care and outcomes in Ontario

BACKGROUND

Studies of potential gender differences in stroke care and outcomes have yielded inconsistent findings. The Project for an Ontario Women's Health Evidence-based Report study measured established stroke care indicators in a large, representative sample of women and men with stroke or transient ischemic attack (TIA) admitted to acute care institutions in the province of Ontario, Canada.

METHODS

The Registry of the Canadian Stroke Network performs a biennial audit on a random sample of 20% of patients with stroke or TIA seen at more than 150 acute care institutions across Ontario. We used data from the 2004/05 audit to compare stroke care by gender, with stratification by age and neighborhood income.

RESULTS

The sample consisted of 4,046 patients (51% women). There were no significant gender differences in the use of thrombolysis, neuroimaging, carotid imaging, dysphagia screening, antithrombotic therapy, or neurology and other consultations. Women with ischemic stroke or TIA were less likely than men to be prescribed statins or undergo carotid imaging and endarterectomy within 6 months of stroke; women were more likely than men to receive antihypertensives. There were no significant gender differences in readmission or mortality rates after stroke.

INTERPRETATION

In this population-based study, we found little evidence of gender differences in stroke care or outcomes other than lipid-lowering therapy, carotid imaging, and endarterectomy. Further study is needed to assess the contribution of the provincial stroke strategy in eliminating gender differences in management of acute stroke and to better understand and target remaining gender differences in management.

Gender differences in treatment of severe carotid stenosis after transient ischemic attack

BACKGROUND AND PURPOSE

Gender differences in carotid endarterectomy (CEA) rates after transient ischemic attack are not well studied, although some reports suggest that eligible men are more likely to have CEA than women after stroke.

METHODS

We retrospectively identified all patients diagnosed with transient ischemic attack and >or=70% carotid stenosis on ultrasound in 2003 to 2004 from 19 emergency departments. Medical records were abstracted for clinical data; 90-day follow-up events, including stroke, cardiovascular events, or death; CEA within 6 months; and postoperative 30-day outcomes. We assessed gender as a predictor of CEA and its complications adjusting for demographic and clinical variables as well as time to CEA between groups.

RESULTS

Of 299 patients identified, 47% were women. Women were older with higher presenting systolic blood pressure and less likely to smoke or to have coronary artery disease or diabetes. Fewer women (36.4%) had CEA than men (53.8%; P=0.004). Reasons for withholding surgical treatment were similar in women and men, and there were no differences in follow-up stroke, cardiovascular event, postoperative complications, or death. Time to CEA was also significantly delayed in women.

CONCLUSIONS

Women with severe carotid stenosis and recent transient ischemic attack are less likely to undergo CEA than men, and surgeries are more delayed.