Under-Enrollment of Women in Stroke Clinical Trials: What Are the Causes and What Should Be Done About It?

Exploring the experiences of an exercise-based telerehabilitation program among Canadian community-dwelling adults with stroke

PURPOSE

Telerehabilitation is emerging as a means for delivering stroke rehabilitation to address unmet lower extremity rehabilitation needs. However, there is currently limited and low-quality evidence supporting the use telerehabilitation interventions for lower extremity recovery after stroke. Thus, we developed an exercise-based telerehabilitation program (TRAIL) for safe and effective promotion of lower extremity function after stroke. This study reports on the qualitative findings from the feasibility study of the TRAIL program.

METHODS

An interpretive description methodology and inductive thematic analysis approach were undertaken. One-on-one semi-structured interviews were conducted on a subset of participants who completed the TRAIL feasibility study. Participants were recruited via email and enrolled into the study based on pre-determined purposeful sampling strategies.

RESULTS

Ten participants (6 men, 4 women) completed a semi-structured interview. Two main themes emerged: (i) TRAIL ingredients for success and (ii) telerehabilitation is a viable option for stroke rehabilitation.

CONCLUSION

Exercise-based telerehabilitation appears to be well-received by men and women post-stroke when social support, professional guidance, and program resources are offered. TRAIL may also prolong the continuum of care that individuals receive once they are discharged back into the community, and contribute to improvements in mobility, lower extremity strength and balance.

Sex, racial, and ethnic disparities in motor neuron disease: clinical trial enrolment

OBJECTIVE

Motor neuron disease (MND) is a group of neurological diseases, the majority being amyotrophic lateral sclerosis (ALS), with varying clinical presentations across demographics. Clinical trial enrollment reflecting global disease burden improves understanding of diverse presentations and aids personalized therapy development. We assessed the sex, racial, and ethnic composition of MND/ALS clinical trial participants relative to global disease burdens.

METHODS

We searched 'motor neuron disease OR amyotrophic lateral sclerosis' on ClinicalTrials.gov from 02/2000-04/2024. We extracted trial (start year, study site, sponsor location, phase, masking, intervention) and demographic data (sex, race, ethnicity) from randomized interventional studies. We obtained sex-based MND/ALS disease burden estimates from the Global Burden of Disease database. For females, we calculated pooled participation-to-prevalence ratio (PPR) with 95% confidence intervals (CIs), with PPR of 0.8-1.2 indicating adequate enrollment. We used Kruskal-Wallis tests to compare demographic groups across trial characteristics.

RESULTS

Of 85 trials, females comprised 37.47% (n = 5011) of 13,372 participants; the pooled female PPR was 0.97 (95% CI: 0.77-1.16). Of 41 trials (9340 participants) reporting race, 121 (1.30%) participants were Black or African American, 16 (0.17%) American Indian or Alaskan Native, and 6 (0.06%) Native Hawaiian or Other Pacific Islander. 24 trials (595 participants) reported ethnicity, with a minority of Hispanic participants (n = 153; 2.57%).

CONCLUSIONS

MND/ALS clinical trials had adequate female enrollment relative to global disease burdens. Race and ethnicity data were underreported. However, there were enrollment disparities of racial and ethnic groups. Increased trial leadership diversity, equitable enrollment policies, and addressing barriers to participation could improve enrollment diversity.

The implementation of sex-and gender-based considerations in exercise-based randomized controlled trials in individuals with stroke: A cross-sectional study

Emerging evidence suggests that sex-and gender-based factors may influence responses to exercise post-stroke. The Sex and Gender Equity in Research (SAGER) guidelines (2016) published international standards for terminology and considerations for research design and trial reporting. The extent to which sex- and gender-based considerations have been implemented in stroke exercise trials is currently unknown. The objective of this cross-sectional study was to compare the proportion of studies that have implemented sex/gender considerations before and after the publication of the SAGER guidelines. We conducted a comprehensive search of the literature to identify exercise-based trials in individuals with stroke. Study titles, abstracts, introductions (hypothesis statements), methods, results and discussions were assessed for adherence to the SAGER guidelines. The proportion of studies adhering to SAGER guidelines published prior to and including December 31, 2016 and from 2017-March 2023 were compared. Of the 245 studies identified, 150 were published before December 31, 2016, of which 0 (0%) titles/abstracts, 0 (0%) introductions, 21 (14.0%) methods, 8 (5.3%) results, and 7 (4.7%) discussion sections adhered to the SAGER guidelines, and 35 (23.3%) reported proper sex and gender terminology. Of the 95 studies published between 2017-2023, 0 (0%) title/abstracts, 1 (1.0%) introduction, 16 (16.8%) methods, 5 (5.3%) results, and 10 (10.5%) discussion sections adhered to the guidelines, and 37 (38.9%) of studies included proper terminology. The implementation of sex- and gender-based considerations in stroke exercise trials is low, but positively the reporting of proper terminology has increased since the publication of standardized reporting guidelines. This study serves as a call to action for stroke rehabilitation researchers to incorporate sex- and gender-based considerations in all stages of research studies, to improve the rigour and generalizability of findings, and promote health equity.

Stem cell therapy: a new hope for stroke and traumatic brain injury recovery and the challenge for rural minorities in South Carolina

Stroke and traumatic brain injury (TBI) are a significant cause of death and disability nationwide. Both are considered public health concerns in rural communities in the state of South Carolina (SC), particularly affecting the African American population resulting in considerable morbidity, mortality, and economic burden. Stem cell therapy (SCT) has emerged as a potential intervention for both diseases with increasing research trials showing promising results. In this perspective article, the authors aim to discuss the current research in the field of SCT, the results of early phase trials, and the utilization of outcome measures and biomarkers of recovery. We searched PubMed from inception to December 2023 for articles on stem cell therapy in stroke and traumatic brain injury and its impact on rural communities, particularly in SC. Early phase trials of SCT in Stroke and Traumatic Brain injury yield promising safety profile and efficacy results, but the findings have not yet been consistently replicated. Early trials using mesenchymal stem cells for stroke survivors showed safety, feasibility, and improved functional outcomes using broad and domain-specific outcome measures. Neuroimaging markers of recovery such as Functional Magnetic Resonance Imaging (fMRI) and electroencephalography (EEG) combined with neuromodulation, although not widely used in SCT research, could represent a breakthrough when evaluating brain injury and its functional consequences. This article highlights the role of SCT as a promising intervention while addressing the underlying social determinants of health that affect therapeutic outcomes in relation to rural communities such as SC. It also addresses the challenges ethical concerns of stem cell sourcing, the high cost of autologous cell therapies, and the technical difficulties in ensuring transplanted cell survival and strategies to overcome barriers to clinical trial enrollment such as the ethical concerns of stem cell sourcing, the high cost of autologous cell therapies, and the technical difficulties in ensuring transplanted cell survival and equitable healthcare.

Sex Difference in the Treatment of Dupuytren's Disease: A Systematic Review and Meta-Analysis of Clinical Trials

Purpose: The aim of this study was to assess the sex differences in enrollment into clinical trials for Dupuytren's disease (DD), treatment efficacy, and complications. Methods: Three databases were searched; Ovid MEDLINE, Ovid EMBASE, and EBSCO CINAHL. Included studies were clinical trials on adult patients with DD. Exclusion criteria were non-English studies and other study designs. Two independent reviewers completed abstract screening, full-text review, and data extraction. The number and percentage of studies that reported ad hoc analyses for sex differences in treatment efficacy, tolerability, and complications were reported. A meta-analysis was performed on the proportion of female participants enrolled in clinical trials for DD. Results: A total of 3172 references were screened, and 59 studies were identified for full-text review. We identified 28 clinical trials for DD of which none reported secondary analyses for sex differences. Only 2 trials discussed sex differences in complications, and one trial reported sex differences in tolerability. The proportion of female participants in the meta-analysis was 19.5% [95% CI: 16.1-23.0%]. Conclusion: Sex differences in the clinical trials for DD are not widely considered in clinical trials despite their critical role. Males and females do not have equal representation in clinical trials for DD. Future studies should account for sex differences in the design and the analysis of clinical trials.

Minorities are under-reported and females are under-represented in stroke motor recovery trials

BACKGROUND

Inclusion of diverse patient populations in stroke rehabilitation clinical trials is key for generalizability and detecting differences in subgroups. The aim of this study was to assess the reporting and inclusion of race, ethnicity, and sex in publications in post-stroke motor recovery clinical trials over the past 5 years.

METHODS

We conducted a systematic review of stroke motor recovery trials conducted only within the United States with at least one control group and published between 2019 and 2023. The percent of racial minorities, ethnicities, and women enrolled in the trials was extracted and calculated for those trials using available data found in the manuscript or on clinicaltrials.gov.

RESULTS

Sixty-eight trials (total of 2,801 participants) met the inclusion criteria and were included in the analysis. 100%, 35%, and 21% of the trials included reported enrollment by sex, race, and ethnicity in the manuscript. All publications reported sex and 38% of the subjects were female. Among the trials reporting race, 59% of the participants were White, followed by 34% Black, 0.4% Native American, 4% Asian, and 3% Other. Among the trials that reported ethnicity, Hispanic or Latino participants were represented as 13% of the total participants.

CONCLUSIONS

In the past 5 years, while all stroke rehab trial publications reported data on sex, they underrepresented women. Most publications did not report race or ethnicity. Improvement in reporting of race/ethnicity in stroke motor recovery trials is needed for understanding of progress with inclusion, and improvement in inclusion of women is needed for better generalizability.

Diverging Trends in Survival and Functional Outcome between Males and Females after Intracerebral Hemorrhage

BACKGROUND

Compared to ischemic stroke, sex differences in patient outcomes following intracerebral hemorrhage (ICH) are underreported. We aimed to determine sex differences in mortality and functional outcomes in a large, unselected Swedish cohort.

METHODS

In this observational study, data on 22,789 patients with spontaneous ICH registered in the Swedish Stroke Register between 2012 and 2019 were used to compare sex differences in 90-day mortality and functional outcome using multivariable Cox and logistic regression analyses, adjusting for relevant confounders. Multiple imputation was used to impute missing data.

RESULTS

The crude 90-day mortality rate was 36.7% in females (3,820/10,405) and 31.7% in males (3,929/12,384) (female hazard ratio [HR] 1.20 95% confidence interval [CI]: 1.15-1.25). In multivariable analysis, the HR for 90-day mortality following ICH in females was 0.89 (95% CI: 0.85-0.94). Age was an important driving factor for the effect of sex on mortality. After adjustment for age, vascular risk factors, and stroke severity, the 90-day functional outcome in pre-stroke independent patients was worse in females compared to males (odds ratio: 1.27 95% CI: 1.16-1.40).

CONCLUSION

In this large observational study, despite lower 90-day mortality, the female sex was independently associated with a worse functional outcome compared to males after ICH, even after adjusting for significant covariates. These diverging trends have not been previously reported for ICH. Given the observational design, our findings should be interpreted with caution, thus further external validation is warranted.

Female Enrollment in Rehabilitation Trials: A Systematic Review of Reporting Sex and Female Participation in Randomized Controlled Trials of Poststroke Upper Extremity Rehabilitation Over 50 Years

OBJECTIVE

To systematically assess the reporting of sex and the percentage of female participants in randomized controlled trials (RCTs) examining interventions for the post-stroke rehabilitation of upper extremity (UE) motor disorders.

DATA SOURCES

CINAHL, Embase, PubMed, Scopus and Web of Science were searched from 1960 to April 1, 2021. Additional articles were identified using the Evidence-Based Review of Stroke Rehabilitation.

STUDY SELECTION

Studies were eligible for inclusion if they (1) were RCTs or crossovers published in English, (2) ≥50% of participants were diagnosed and affected by stroke, (3) included adults ≥18 years old, and (4) applied an intervention to the hemiparetic UE as the primary objective of the study.

DATA EXTRACTION

Two investigators independently screened the title and abstracts, and duplicates were removed. A full-text review was done for studies that met all inclusion criteria. Data were extracted using a custom data extraction template in Covidence and were transferred to online Excel (V16) for data management. Study characteristics and extracted variables were summarized using standard descriptive statistics. Data analyses were performed using SPSS (V29.0).

DATA SYNTHESIS

A total of 1276 RCTs met inclusion criteria, and of these, 5.2% did not report results on sex, accounting for 5.6% of participants. Women have been underrepresented in stroke RCTs, accounting for 38.8% of participants. Female participation was greater in the acute poststroke phase than in the chronic and subacute phases. Over almost 5 decades, there has been a small decrease in the proportion of female participants in these trials.

CONCLUSIONS

Evidence-based medicine for the treatment and prevention of stroke is guided by results from RCTs. Generalizability depends on sufficient representation in clinical trials. Stakeholders, such as funders and journal editors, play a key role in encouraging researchers to enroll enough of both sexes and to report the presence or absence of sex differences in RCTs.

Examining Sex Differences in Relationships Between Subjective and Objective Measures of Upper Extremity Motor Impairment in a Sample of Stroke Survivors

BACKGROUND AND PURPOSE

Rehabilitation professionals use subjective and objective outcome measures to assess stroke-related impact and impairment. Understanding if subjective and objective findings correlate among stroke survivors, especially if these associations differ between females and males, can inform care decisions.

METHODS

A retrospective cross-sectional design was used, with data selected from subacute to chronic stroke survivors on age, time since stroke, the hand domain from the Stroke Impact Scale version 3.0 (SIS-H), and the Fugl-Meyer Upper Extremity (FMUE) Assessment. Group differences were assessed for all outcomes based on sex and time poststroke. Separate correlations for females and males were performed between the subjective (SIS-H) and objective measures (FMUE) of upper limb function and impairment.

RESULTS

Data from 148 participants (44 females) were included in this study. SIS-H was significantly correlated with FMUE in both females and males ( P s ≤ 0.001). No significant differences were found between the groups' mean SIS-H or FMUE scores based on sex or time poststroke.

DISCUSSION AND CONCLUSIONS

Subjective and objective measures of physical functioning were correlated in both females and males. Although we found no sex differences in our primary outcomes, the sample size of females was disproportionately lower than the males. This is consistent with an ongoing problem in the stroke recovery research field, where females are often underrepresented and understudied, and where females who experience higher levels of impairment are less likely to participate in research.

The impact of sex and gender on advanced stroke interventions and end-of-life outcomes after stroke

OBJECTIVES

In this review, we examine the impact of sex and gender on advanced stroke interventions and end-of-life outcomes after stroke and discuss the current theories, available evidence, and gaps in the literature.

METHODS

A scoping review of the literature was conducted to determine gender differences on advanced stroke interventions and end-of-life outcomes after stroke. The study team utilized PubMed to conduct a review of the literature and included research studies related to sex, gender, advanced stroke interventions, and end-of-life outcomes after stroke. The PRISMA process for conducting a scoping review was followed.

RESULTS

This review found that although evidence regarding gender differences in advanced stroke interventions and end-of-life care after stroke is disparate, some gender differences do indeed exist. Women are less likely to receive thrombectomy or alteplase, women are more likely to receive palliative care intervention, hospice, and women experience stroke mortality at higher rates.

CONCLUSIONS

Gender differences in end-of-life care after stroke are apparent with women experiencing lower rates of life sustaining interventions, and higher rates of mortality, palliative and hospice care. More research is needed to identify variables associated with or responsible for gender differences during advance interventions and end-of-life care after stroke.

Importance of sex and gender differences in enrollment and interpretation of stroke clinical trials

OBJECTIVES

This review aims to reinforce the importance of improving sex balance in preclinical trials and sex and gender diversity and proportional balance in clinical trials enrollment and how this influences interpretation of stroke clinical trials. It also aims to identify strategies for improvement in data collection.

MATERIALS AND METHODS

A PubMed search was conducted of publications in English, using MeSH terms sex, sex characteristics, gender identity, transgender, gender-nonconforming persons, clinical trials as topic, stroke. Of 249 search results, 217 were human or animal studies related to stroke, the majority of which were reviews, secondary analyses of stroke clinical trials, meta analyses, or retrospective studies, subject to the methods of sex and gender acquisition per the primary data source. Articles were reviewed, noting inclusion or absence of sex and gender definitions and trial design. Selected articles were supplemented with United States Food and Drug Administration, National Institutes of Health, and National Academy of Science, Engineering, and Medicine publications.

RESULTS

The majority of preclinical studies continue to report sex as a binary variable, and the majority of stroke clinical trials report sex and gender as interchangeable and binary. Mindful trial design and statistical analysis can improve accuracy in the interpretation of sex and gender differences. Guidance exists to improve reporting on currently accepted sex and gender definitions, recommended data collection instruments, and appropriate statistical analyses.

CONCLUSIONS

Despite acknowledgement of having failed to achieve diverse and proportionally balanced enrollment, sex and gender imbalance across the research continuum remains prevalent. Responsible incorporation of sex and gender in stroke clinical trials can be achieved through thoughtful study design, use of contemporary sex and gender definitions, inclusive prospective data collection, balanced enrollment with prespecified goals, and appropriate statistical analysis.

A Systematic Review of Female Participation in Randomized Controlled Trials of Post-Stroke Upper Extremity Rehabilitation in Low- to Middle-Income Countries and High-Income Countries and Regions

INTRODUCTION

Female participation is lower than males in both acute stroke and stroke rehabilitation trials. However, less is known about how female participation differs across countries and regions. This study aimed to assess the percentage of female participants in randomized controlled trials (RCTs) of post-stroke rehabilitation of upper extremity (UE) motor disorders in low-middle-income (LMICs) and high-income countries (HICs) as well as different high-income world regions.

METHODS

CINAHL, Embase, PubMed, Scopus, and Web of Science were searched from 1960 to April 1, 2021. Studies were eligible for inclusion if they (1) were RCTs or crossovers published in English; (2) ≥50% of participants were diagnosed with stroke; 3) included adults ≥18 years old; and (4) applied an intervention to the hemiparetic UE as the primary objective of the study. Countries were divided into HICs and LMICs based on their growth national incomes. The HICs were further divided into the three high-income regions of North America, Europe, and Asia and Oceania. Data analysis was performed using SPSS and RStudio v.4.3.1.

RESULTS

A total of 1,276 RCTs met inclusion criteria. Of them, 298 RCTs were in LMICs and 978 were in HICs. The percentage of female participants was significantly higher in HICs (39.5%) than LMICs (36.9%). Comparing high-income regions, there was a significant difference in the overall female percentages in favor of RCTs in Europe compared to LMICs but not North America or Asia and Oceania. There was no significant change in the percentage of female participants in all countries and regions over the last 2 decades, with no differences in trends between the groups.

CONCLUSIONS

Sufficient female representation in clinical trials is required for the generalizability of results. Despite differences in overall percentage of female participation between countries and regions, females have been underrepresented in both HICs and LMICs with no considerable change over 2 decades.

Pre-Implementation Analysis of the Usability and Acceptability of a Poststroke Complex Telehealth Biofeedback Intervention

IMPORTANCE

Complex telehealth interventions can facilitate remote occupational therapy services and improve access for people living with chronic neurological conditions. Understanding the factors that influence the uptake of these technologies is important.

OBJECTIVE

To explore the fit between electromyography (EMG) biofeedback and telerehabilitation for stroke survivors, optimize EMG biofeedback interventions, and, more broadly, support other efforts to develop complex telerehabilitation interventions.

DESIGN

Pre-implementation mixed-methods analysis of usability and acceptability data collected during a pilot and feasibility study.

SETTING

Community.

PARTICIPANTS

Adult stroke survivors with hemiparesis (N = 11; M age = 54 yr).

INTERVENTION

Game-based EMG biofeedback system for arm sensorimotor rehabilitation, delivered via telehealth.

OUTCOMES AND MEASURES

Post-Study System Usability Questionnaire, an extended Unified Theory of Acceptance and Use of Technology model questionnaire, and semistructured interview. We coded the interview data using questionnaire constructs.

RESULTS

Participants used an EMG biofeedback intervention at home. Quantitative measures show high levels of perceived usability and acceptability, supported by qualitative findings describing specific facilitators and barriers.

CONCLUSIONS AND RELEVANCE

Pre-implementation studies can improve the design and relevance of complex telehealth interventions. One major conclusion from this study is the influence of therapy providers on acceptability and usability of complex telehealth interventions. Plain-Language Summary: This study contributes to an emerging body of literature that examines the use of complex telehealth interventions with survivors of neurological injury. The findings highlight the value and support the development and use of complex telehealth interventions, which have the potential to improve remote access to occupational therapy for clients living with chronic neurological conditions. Complex telehealth interventions can open doors for survivors of neurological injury who face barriers to accessing occupational therapy and would benefit from technology-enabled therapy at home.

Barriers to Enrollment in a Post-Stroke Neuromodulation and Walking Study: Implications for Recruiting Women

BACKGROUND

Women have a higher risk of stroke and related disability than men but are underrepresented in stroke clinical trials. Identifying modifiable recruitment and enrollment barriers for women can improve study generalizability, statistical power, and resource utilization.

OBJECTIVE

In a post-stroke neuromodulation study, we determined the impact of sex on the occurrence of exclusion criteria and compared the sex distribution of screened and enrolled individuals with a broader stroke-affected population.

METHODS

A total of 335 individuals with chronic stroke were screened for a study examining how neuromodulation and high-intensity treadmill training affect walking speed and corticomotor excitability. Demographics and exclusions were retrospectively gathered as a secondary dataset. Exclusion criteria consisted of 6 categories (not target population, unable to do treadmill protocol, unable to do non-invasive brain stimulation, insufficient ankle motion and disinterest, and cognitive impairment). Incidence of each exclusion criterion was compared between women and men. The sex distribution was compared to a dataset from Chicago primary stroke centers.

RESULTS

A total of 81 individuals were enrolled and 254 were not. The percentage of women excluded was significantly greater than that of men (P = .04). No individual exclusion criterion or categories excluded women more frequently than men. Screened and enrolled individuals had a lower proportion of women and younger age than a representative stroke population (P < .001).

CONCLUSIONS

We identified exclusion criteria (ie, headaches, cognitive scores, and age) that are modifiable barriers to enrollment of women in this post-stroke neuromodulation study. Addressing underrepresentation of women in stroke research is pivotal for enhancing generalizability, achieving statistical power, and optimizing resources.

Diversity in randomized clinical trials for peripheral artery disease: a systematic review

BACKGROUND

Significant race and sex disparities exist in the prevalence, diagnosis, and outcomes of peripheral artery disease (PAD). However, clinical trials evaluating treatments for PAD often lack representative patient populations. This systematic review aims to summarize the demographic representation and enrollment strategies in clinical trials of lower-extremity endovascular interventions for PAD.

METHODS

Following the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched multiple sources (Medline, EMBASE, Cochrane, Clinicaltrials.gov, WHO clinical trial registry) for randomized controlled trials (RCTs), RCT protocols, and peer-reviewed journal publications of RCTs conducted between January 2012 and December 2022. Descriptive analysis was used to summarize trial characteristics, publication or study protocol characteristics, and the reporting of demographic characteristics. Meta-regression was used to explore associations between demographic characteristics and certain trial characteristics.

RESULTS

A total of 2,374 records were identified. Of these, 59 met the inclusion criteria, consisting of 35 trials, 14 publications, and 10 protocols. Information regarding demographic representation was frequently missing. While all 14 trial publications reported age and sex, only 4 reported race/ethnicity, and none reported socioeconomic or marital status. Additionally, only 4 publications reported clinical outcomes by demographic characteristics. Meta-regression analysis revealed that 6% more women were enrolled in non-European trials (36%) than in European trials (30%).

CONCLUSIONS

The findings of this review highlight potential issues that may compromise the reliability and external validity of study findings in lower-extremity PAD RCTs when applied to the real-world population. Addressing these issues is crucial to enhance the generalizability and impact of clinical trial results in the field of PAD, ultimately leading to improved clinical outcomes for patients in underrepresented populations.

REGISTRATION

The systematic review methodology was published in the International Prospective Register of Systematic Reviews (PROSPERO: CRD42022378304).

Sex-Based Analysis of Workflow and Outcomes in Acute Ischemic Stroke Patients Treated With Alteplase Versus Tenecteplase

BACKGROUND

Understanding sex differences in stroke care is important in reducing potential disparities. Our objective was to explore sex differences in workflow efficiency, treatment efficacy, and safety in the AcT trial (Alteplase Compared to Tenecteplase).

METHODS

AcT was a multicenter, registry-linked randomized noninferiority trial comparing tenecteplase (0.25 mg/kg) with alteplase (0.9 mg/kg) in acute ischemic stroke within 4.5 hours of onset. In this post hoc analysis, baseline characteristics, workflow times, successful reperfusion (extended Thrombolysis in Cerebral Infarction score ≥2b), symptomatic intracerebral hemorrhage, 90-day functional independence (modified Rankin Scale score, 0-1), and 90-day mortality were compared by sex. Mixed-effects regression analysis was used adjusting for age, stroke severity, and occlusion site for outcomes.

RESULTS

Of 1577 patients treated with intravenous thrombolysis (2019-2022), 755 (47.9%) were women. Women were older (median, 77 [68-86] years in women versus 70 [59-79] years in men) and had a higher proportion of severe strokes (National Institutes of Health Stroke Scale score >15; 32.4% versus 24.9%) and large vessel occlusions (28.7% versus 21.5%) compared with men. All workflow times were comparable between sexes. Women were less likely to achieve functional independence (31.7% versus 39.8%; unadjusted relative risk, 0.80 [95% CI, 0.70-0.91]) and had higher mortality (17.7% versus 13.3%; unadjusted relative risk, 1.33 [95% CI, 1.06-1.69]). Adjusted analysis showed no difference in outcomes between sexes.

CONCLUSIONS

Differences in prognostic factors of age, stroke severity, and occlusion site largely accounted for higher functional dependence and mortality in women. No sex disparities were apparent in workflow quality indicators. Given the integration of the AcT trial into clinical practice, these results provide reassurance that no major sex biases are apparent in acute stroke management throughout participating Canadian centers.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03889249.

A life-course approach to tackling noncommunicable diseases in women

Women's health has been critically underserved by a failure to look beyond women's sexual and reproductive systems to adequately consider their broader health needs. In almost every country in the world, noncommunicable diseases are the leading causes of death for women. Among these, cardiovascular disease (including heart disease and stroke) and cancer are the major causes of mortality. Risks for these conditions exist at each stage of women's lives, but recognition of the unique needs of women for the prevention and management of noncommunicable diseases is relatively recent and still emerging. Once they are diagnosed, treatments for these diseases are often costly and noncurative. Therefore, we call for a strategic, innovative life-course approach to identifying disease triggers and instigating cost-effective measures to minimize exposure in a timely manner. Prohibitive barriers to implementing this holistic approach to women's health exist in both the social arena and the medical arena. Recognizing these impediments and implementing practical approaches to surmounting them is a rational approach to advancing health equity for women, with ultimate benefits for society as a whole.

Antiplatelet Agent Use After Stroke due to Intracerebral Hemorrhage

This focused update about antiplatelet agents to reduce the high risk of major adverse cardiovascular events after stroke due to spontaneous (nontraumatic) intracerebral hemorrhage (ICH) complements earlier updates about blood pressure-lowering, lipid-lowering, and oral anticoagulation or left atrial appendage occlusion for atrial fibrillation after ICH. When used for secondary prevention in people without ICH, antiplatelet agents reduce the risk of major adverse cardiovascular event (rate ratio, 0.81 [95% CI, 0.75-0.87]) and might increase the risk of ICH (rate ratio, 1.67 [95% CI, 0.97-2.90]). Before 2019, guidance for clinical decisions about antiplatelet agent use after ICH has focused on estimating patients' predicted absolute risks and severities of ischemic and hemorrhagic major adverse cardiovascular event and applying the known effects of these drugs in people without ICH to estimate whether individual ICH survivors in clinical practice might be helped or harmed by antiplatelet agents. In 2019, the main results of the RESTART (Restart or Stop Antithrombotics Randomized Trial) randomized controlled trial including 537 survivors of ICH associated with antithrombotic drug use showed, counterintuitively, that antiplatelet agents might not increase the risk of recurrent ICH compared to antiplatelet agent avoidance over 2 years of follow-up (12/268 [4%] versus 23/268 [9%]; adjusted hazard ratio, 0.51 [95% CI, 0.25-1.03]; P=0.060). Guidelines in the United States, Canada, China, and the United Kingdom and Ireland have classified the level of evidence as B and indicated that antiplatelet agents may be considered/reasonable after ICH associated with antithrombotic agent use. Three subsequent clinical trials have recruited another 174 participants with ICH, but they will not be sufficient to determine the effects of antiplatelet therapy on all major adverse cardiovascular events reliably when pooled with RESTART. Therefore, ASPIRING (Antiplatelet Secondary Prevention International Randomized Study After Intracerebral Hemorrhage) aims to recruit 4148 ICH survivors to determine the effects of antiplatelet agents after ICH definitively overall and in subgroups.

Gender Disparities in Cardiac Surgery Trials: Leadership, Authorship, and Patient Enrollment

BACKGROUND

Studies have highlighted the paucity of women-led randomized controlled trials (RCTs) in cardiovascular medicine. Whether this finding also applies to cardiac surgery has not been evaluated. In this study, we evaluate women authorship, leadership, and women enrollment in cardiac surgery RCTs.

METHODS

A systematic literature search was conducted to identify RCTs comparing 2 or more adult cardiac surgical procedures published from 2000 to 2022. Women-led RCTs were defined as those with a woman as either a first or last author. Linear regression and correlation analyses were used.

RESULTS

Of 58 RCTs, 8 (13.8%) were women-led; 17 (29.3%) RCTs had no women authors. Overall, 17.9% of all authors were women, but only 1.2% of all authors were women cardiac surgeons and only 19% of the RCTs had a women cardiac surgeon among the authors. The median proportion of women authors was 14.3% by RCT, which was significantly higher in women-led compared with men-led RCTs (28.6% vs 11.8%; P = .01). No significant change in the proportion of women authors was observed during the study period. North American RCTs had a higher proportion of women authors compared with other geographic regions (28.6% vs 12.5%; P = .01). No correlation was found between the proportion of women authors and the proportion of women participants enrolled in individual RCTs.

CONCLUSIONS

During the last 2 decades, only a minority of cardiac surgery RCTs were women-led, and no significant increase in women authorship occurred. There are important geographic differences in women authorship.

Acceptability of a Telerehabilitation Biofeedback System Among Stroke Survivors: A Qualitative Analysis

Electromyography (EMG) biofeedback delivered via telerehabilitation can increase access to occupational therapy services for stroke survivors with severe impairment, but there is limited research on its acceptability. This study identified factors influencing the acceptability of a complex, muscle biofeedback system (Tele-REINVENT) for upper extremity sensorimotor stroke telerehabilitation among stroke survivors. We conducted interviews with stroke survivors (n = 4) who used Tele-REINVENT at home for 6 weeks and analyzed the data with reflexive thematic analysis. Biofeedback, customization, gamification, and predictability affected the acceptability of Tele-REINVENT among stroke survivors. Across themes, features and experiences that gave participants agency and control were more acceptable. Our findings contribute to the design and development of at-home EMG biofeedback interventions, which can improve access to advanced occupational therapy treatment options for those who need it most.

Clinical Trial Participation and COVID-19: a Descriptive Analysis from the American Heart Association's Get With The Guidelines Registry

As COVID-19 cases begin to decrease in the USA, learning from the pandemic experience will provide insights regarding disparities of care delivery. We sought to determine if specific populations hospitalized with COVID-19 are equally likely to be enrolled in clinical trials. We examined patients hospitalized with COVID-19 at centers participating in the American Heart Association's COVID-19 CVD Registry. The primary outcome was odds of enrollment in a clinical trial, according to sex, race, and ethnicity. Among 14,397 adults hospitalized with COVID-19, 9.5% (n = 1,377) were enrolled in a clinical trial. The proportion of enrolled patients was the lowest for Black patients (8%); in multivariable analysis, female and Black patients were less likely to be enrolled in a clinical trial related to COVID-19 compared to men and other racial groups, respectively. Determination of specific reasons for the disparities in trial participation related to COVID-19 in these populations should be further investigated.

The safety and feasibility of early cardiorespiratory fitness testing after stroke

BACKGROUND

Cardiorespiratory fitness testing is recommended as part of a pre-exercise evaluation to aid the programming of safe, tailored cardiorespiratory fitness training after stroke. But there is limited evidence for its safety and feasibility in people with stroke with varying impairment levels in the early subacute phase of stroke recovery.

OBJECTIVE

To assess the safety and feasibility of cardiorespiratory fitness testing in the early subacute phase after stroke.

DESIGN

A sub-study of a larger single service, multi-site, prospective cohort feasibility study (Cardiac Rehabilitation in Stroke Survivors to Improve Survivorship [CRiSSIS]).

SETTING

Private subacute inpatient rehabilitation facilities.

PARTICIPANTS

Consecutive admissions of people with ischemic stroke admitted to subacute rehabilitation facilities.

INTERVENTION

Not applicable.

MAIN OUTCOME(S)

Safety was determined by the occurrence of adverse or serious adverse events. Feasibility was determined by assessing the (1) number of participants recruited and (2) number of participants able to complete the fitness test.

RESULTS

Between April 2018 and December 2019, a total of 165 people with stroke were screened to participate; 109 were eligible and 65 were recruited. Of the 62 who completed testing, 41 participants were able to complete a submaximal fitness test at a median of 12 days post-stroke. One minor adverse event was recorded. Of the 21 participants unable to complete the fitness test; 4 declined to complete the test, 9 were unable to commence the test, and 8 were unable to complete the first stage of the protocol due to stroke-related impairments. Participants with mild stroke, greater motor and cognitive function, and fewer depressive symptoms were more likely to be able to complete the cardiorespiratory fitness test.

CONCLUSION

Cardiorespiratory fitness testing was safe for most people with mild-to-moderately severe ischemic stroke and transient ischemic attack in the early subacute phase, but only two-thirds of the participants could complete the test.

Sex and gender reporting in Australian health and medical research publications

OBJECTIVE

This study aimed to determine how sex and gender are being incorporated into Australian medical research publications and if this is influenced by journals endorsing the International Committee of Medical Journal Editors (ICMJE) guidelines, which contain criteria for sex and gender reporting.

METHODS

Analysis of original research articles published in Australia's top 10 medical journals in 2020.

RESULTS

From the 10 leading journals, 1,136 articles were eligible for analysis, including 990 human participant populations. Sex and/or gender were reported for 873 (88.2%) human populations, with 480 using conflicting terminology. Only 14 (1.6%) described how sex and gender were determined. The primary outcome, or key aim, was stratified by sex and/or gender for 249 (29.2%) participant groups and the influence of sex and/or gender on the results was discussed for only 171 (17.3%). There was no significant association between endorsement of the ICMJE guidelines and adherence to any sex and gender criteria.

CONCLUSIONS

Sex and gender are poorly incorporated into Australian medical research publications and was not improved by journals endorsing the ICMJE guidelines.

IMPLICATIONS FOR PUBLIC HEALTH

Reporting and analysis of sex and gender data in health research in Australian medical journals requires improvement, for better health for all.

Underrepresentation of women in randomized controlled trials: a systematic review and meta-analysis

BACKGROUND

Although regulatory changes towards correcting the underrepresentation of women in randomized controlled trials (RCTs) occurred (National Institutes of Health 1994), concerns exist about whether an improvement is taking place. In this systematic review and meta-analysis, we aimed to assess the inclusion rates of women in recent RCTs and to explore the potential barriers for the enrollment of women.

METHODS

RCTs published in 2017 examining any type of intervention in adults were searched in PubMed and Cochrane Library. The following predefined medical fields were included: cardiovascular diseases, neoplasms, endocrine system diseases, respiratory tract diseases, bacterial and fungal infections, viral diseases, digestive system diseases, and immune system diseases. Studies were screened independently by two reviewers, and an equal number of studies was randomly selected per calendric month. The primary outcome was the enrollment rate of women, calculated as the number of randomized women patients divided by the total number of randomized patients. Rates were weighted by their inverse variance; statistical significance was tested using general linear models (GLM).

RESULTS

Out of 398 RCTs assessed for eligibility, 300 RCTs were included. The enrollment rate of women in all the examined fields was lower than 50%, except for immune system diseases [median enrollment rate of 68% (IQR 46 to 81)]. The overall median enrollment rate of women was 41% (IQR 27 to 54). The median enrollment rate of women decreased with older age of the trials' participants [mean age of trials' participants ≤ 45 years: 47% (IQR 30-64), 46-55 years: 46% (IQR 33-58), 56-62 years: 38% (IQR 27-50), ≥ 63 years: 33% (IQR 20-46), p < 0.001]. Methodological quality characteristics showed no significant association with the enrollment rates of women. Out of the 300 included RCTs, eleven did not report on the number of included women. There was no significant difference between these studies and the studies included in the analysis.

CONCLUSIONS

Women are being inadequately represented, in the selected medical fields analyzed in our study, in recent RCTs. Older age is a potential barrier for the enrollment of women in clinical trials. Low inclusion rates of elderly women might create a lack of crucial knowledge in the adverse effects and the benefit/risk profile of any given treatment. Factors that might hinder the participation of women should be sought and addressed in the design of the study.

Pre-stroke socioeconomic status predicts upper limb motor recovery after inpatient neurorehabilitation

BACKGROUND

Lower socioeconomic status (SES) is associated with higher mortality rates and the likelihood of receiving less evidence-based treatment after stroke. In contrast, little is known about the impact of SES on recovery after discharge from inpatient rehabilitation. The aim of this study was to investigate the influence of SES on long-term recovery after stroke.

PATIENTS AND METHODS

In a prospective, observational, multicentre study, inpatients were recruited towards the end of rehabilitation. The 12-month follow-up focussed on upper limb motor recovery, measured by the Fugl-Meyer score. A clinically relevant improvement of ≥5.25 points was considered recovery. Patient-centric measures such as the Patient-reported Outcomes Measurement Information System-Physical Health (PROMIS-10 PH) provided secondary outcomes. Information on schooling, vocational training, income and occupational status pre-stroke entered a multidimensional SES index. Multivariate logistic regression models calculating odds ratios (ORs) and corresponding confidence intervals (CIs) were applied. SES was added to an initial model including age, sex and baseline neurological deficit. Additional exploratory analyses examined the association between SES and outpatient treatment.

RESULTS

One hundred and seventy-six patients were enrolled of whom 98 had SES and long-term recovery data. Model comparisons showed the SES-model superior to the initial model (Akaike information criterion (AIC): 123 vs. 120, Pseudo R²: 0.09 vs. 0.13). The likelihood of motor recovery (OR = 17.12, 95%CI = 1.31; 224.18) and PROMIS-10 PH improvement (OR = 20.76, 95%CI = 1.28; 337.11) were significantly increased with higher SES, along with more frequent use of outpatient therapy (p = .02).

CONCLUSIONS

Higher pre-stroke SES is associated with better long-term recovery after discharge from rehabilitation. Understanding these factors can improve outpatient long-term stroke care and lead to better recovery.KEY MESSAGEHigher pre-stroke socioeconomic status (SES) is associated with better long-term recovery after discharge from rehabilitation both in terms of motor function and self-reported health status.Higher SES is associated with significantly higher utilization of outpatient therapies.Discharge management of rehabilitation clinics should identify and address socioeconomic factors in order to detect individual needs and to improve outpatient recovery. Article registration: clinicaltrials.gov NCT04119479.

Personal factors understood through the Ecological-Enactive Model of Disability and implications for rehabilitation research

The International Classification of Functioning, Disability and Health (ICF) recognizes that disability arises from the interaction between an individual with a medical condition and the context in which they are embedded. Context in the ICF is comprised of environmental and personal factors. Personal factors, the background life and lifestyle of an individual, are poorly understood in rehabilitation. There is limited knowledge about how personal and environmental factors interact to shape the contextual conditions critical for explaining functioning and disability. In this paper, we explore how a newly proposed model of disability, the Ecological-Enactive Model of Disability, can enhance understanding of personal factors across multiple rehabilitation disciplines. We draw from a review of evidence and phenomenological interviews of individuals with Friedreich's Ataxia. We consider the practical impact of this understanding on disability and rehabilitation research and pathways for the future focusing on representative design.

Sex differences in neurovascular disorders

Neurovascular disorders is a heterogenous group of diseases, including one of the most time critical disorders in emergency medicine; stroke. Sex differences are extensively described in neurovascular disorders, ranging from differences in symptom presentation, risk factors, treatment and outcomes. For example, women with stroke, more often present with generalized weakness, reduced consciousness and headache than men. Furthermore, there are differences in risk factors, outcomes and in the effect of secondary prevention. Women have a higher risk of cerebral venous thrombosis and developing cerebral aneurysms. In general, women have been underrepresented in trials on neurovascular disorders. This chapter provides an extensive overview of sex differences in stroke in general and in the differences specially seen in ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage and in cerebral venous thrombosis.

Contextualising sex and gender research to improve women's health: An early- and mid-career researcher perspective

The field of sex and gender research in health and medicine is growing, and many early- and mid-career researchers (EMCRs) are developing skills in this area. As EMCRs specialising in sex and gender research, we aim to better understand sex- and gender-based determinants of human health, challenge long-standing and pervasive gender biases, and contribute to improving the evidence base upon which clinical guidelines and policy interventions are developed. To effectively achieve these goals, we believe that EMCRs would benefit from understanding the challenges of working in this space and participate in driving change in three key areas. First, in creating greater links between the goals of sex and gender research and addressing systemic bias against women and gender minorities, to effectively translate knowledge about sex and gender differences into improved health outcomes. Second, in expanding the reach of sex and gender research to address women's health in an intersectional way and ensure that it also benefits the health of men, transgender and gender-diverse people and those who are intersex. Third, in working with others in the scientific community to improve methods for sex and gender research, including updating data collection practises, ensuring appropriate statistical analyses and shifting scientific culture to recognise the importance of null findings. By improving focus on these three areas, we see greater potential to translate this research to improve women's health and reduce health inequities for all.

Toward a Better Understanding of Sex- and Gender-Related Differences in Endovascular Stroke Treatment: A Scientific Statement From the American Heart Association/American Stroke Association

There are many unknowns when it comes to the role of sex in the pathophysiology and management of acute ischemic stroke. This is particularly true for endovascular treatment (EVT). It has only recently been established as standard of care; therefore, data are even more scarce and conflicting compared with other areas of acute stroke. Assessing the role of sex and gender as isolated variables is challenging because they are closely intertwined with each other, as well as with patients' cultural, ethnic, and social backgrounds. Nevertheless, a better understanding of sex- and gender-related differences in EVT is important to develop strategies that can ultimately improve individualized outcome for both men and women. Disregarding patient sex and gender and pursuing a one-size-fits-all strategy may lead to suboptimal or even harmful treatment practices. This scientific statement is meant to outline knowledge gaps and unmet needs for future research on the role of sex and gender in EVT for acute ischemic stroke. It also provides a pragmatic road map for researchers who aim to investigate sex- and gender-related differences in EVT and for clinicians who wish to improve clinical care of their patients undergoing EVT by accounting for sex- and gender-specific factors. Although most EVT studies, including those that form the basis of this scientific statement, report patient sex rather than gender, open questions on gender-specific EVT differences are also discussed.

Sex disparities in enrollment and reporting of outcomes by sex in contemporary clinical trials of atrial fibrillation

BACKGROUND

Underrepresentation of females in randomized controlled trials (RCTs) limits generalizability and quality of the evidence guiding treatment of females. This study aimed to measure the sex disparities in participants' recruitment in RCTs of atrial fibrillation (AF) and determine associated factors, and to describe the frequency of outcomes reported by sex.

METHODS

MEDLINE was searched to identify RCTs of AF published between January 1, 2011, and November 20, 2021, in 12 top-tier journals. We measured the enrollment of females using the enrollment disparity difference (EDD) which is the difference between the proportion of females in the trial and the proportion of females with AF in the underlying general population (obtained from the Global Burden of Disease). Random-effects meta-analyses of the EDD were performed, and multivariable meta-regression was used to explore factors associated with disparity estimates. We also determined the proportion of trials that included sex-stratified results.

RESULTS

Out of 1133 records screened, 142 trials were included, reporting on a total of 133 532 participants. The random-effects summary EDD was -0.125 (95% confidence interval [CI] = -0.143 to -0.108), indicating that females were under-enrolled by 12.5 percentage points. Female enrollment was higher in trials with higher sample size (<250 vs. >750, adjusted odds ratio [aOR] 1.065, 95% CI: 1.008-1.125), higher mean participants' age (aOR: 1.006, 95% CI: 1.002-1.009), and lower in trials conducted in North America compared to Europe (aOR: 0.945, 95% CI: 0.898-0.995). Only 36 trials (25.4%) reported outcomes by sex, and of these 29 (80.6%) performed statistical testing of the sex-by-treatment interaction.

CONCLUSION

Females remain substantially less represented in RCTs of AF, and sex-stratified reporting of primary outcomes is infrequent. These findings call for urgent action to improve sex equity in enrollment and sex-stratified outcomes' reporting in RCTs of AF.

Sex-Specific Immune Responses in Stroke

In both acute and chronic diseases, functional differences in host immune responses arise from a multitude of intrinsic and extrinsic factors. Two of the most important factors affecting the immune response are biological sex and aging. Ischemic stroke is a debilitating disease that predominately affects older individuals. Epidemiological studies have shown that older women have poorer functional outcomes compared with men, in part due to the older age at which they experience their first stroke and the increased comorbidities seen with aging. The immune response also differs in men and women, which could lead to altered inflammatory events that contribute to sex differences in poststroke recovery. Intrinsic factors including host genetics and chromosomal sex play a crucial role both in shaping the host immune system and in the neuroimmune response to brain injury. Ischemic stroke leads to altered intracellular communication between astrocytes, neurons, and resident immune cells in the central nervous system. Increased production of cytokines and chemokines orchestrate the infiltration of peripheral immune cells and promote neuroinflammation. To maintain immunosurveillance, the host immune and central nervous system are highly regulated by a diverse population of immune cells which are strategically distributed within the neurovascular unit and become activated with injury. In this review, we provide a comprehensive overview of sex-specific host immune responses in ischemic stroke.

Community Engagement: Lessons Learned From the AAASPS and SDBA

Community engagement is a means to help overcome challenges to the delivery of health care and preventative services. On the occasion of the 2021 International Stroke Conference Edgar J. Kenton III Lecture, I review community engagement strategies utilized in the AAASPS trial (African-American Antiplatelet Stroke Prevention Study) and SDBA (Studies of Dementia in the Black Aged) observational studies that I directed. The main community engagement strategies included use of home visits (bringing the study to the community), engagement of churches, community advisors, community physicians, other healthcare providers, major Black community organizations, and utilization of diversity training. Community engagement strategies were a major component of AAASPS and SDBA that helped to ensure successful recruitment and retention of an underrepresented community in clinical trial and observational studies. Lessons learned from these studies largely carried out in the 1980s and 1990s helped to dispel myths that Blacks could not be recruited into large-scale clinical trials, emphasized the importance of studying underrepresented groups with adequate statistical power to test primary study hypotheses, and provided foundational recruitment and retention methods for future consideration.

The Impact of Sex and Gender on Stroke

Women face a disproportionate burden of stroke mortality and disability. Biologic sex and sociocultural gender both contribute to differences in stroke risk factors, assessment, treatment, and outcomes. There are substantial differences in the strength of association of stroke risk factors, as well as female-specific risk factors. Moreover, there are differences in presentation, response to treatment, and stroke outcomes in women. This review outlines current knowledge of impact of sex and gender on stroke, as well as delineates research gaps and areas for future inquiry.

Representation of Women in Stroke Clinical Trials: A Review of 281 Trials Involving More Than 500,000 Participants

BACKGROUND AND OBJECTIVES

Women have been underrepresented in cardiovascular disease clinical trials but there is less certainty over the level of disparity specifically in stroke. We examined the participation of women in trials according to stroke prevalence in the population.

METHODS

Published randomized controlled trials with ≥100 participants enrolled between 1990 and 2020 were identified from ClinicalTrials.gov. To quantify sex disparities in enrollment, we calculated the participation to prevalence ratio (PPR), defined as the percentage of women participating in a trial vs the prevalence of women in the disease population.

RESULTS

There were 281 stroke trials eligible for analyses with a total of 588,887 participants, of whom 37.4% were women. Overall, women were represented at a lower proportion relative to their prevalence in the underlying population (mean PPR 0.84; 95% confidence interval [CI] 0.81-0.87). The greatest differences were observed in trials of intracerebral hemorrhage (PPR 0.73; 95% CI 0.71-0.74), trials with a mean age of participants <70 years (PPR 0.81; 95% CI 0.78-0.84), nonacute interventions (PPR 0.80; 95% CI 0.76-0.84), and rehabilitation trials (PPR 0.77; 95% CI 0.71-0.83). These findings did not significantly change over the period from 1990 to 2020 (p for trend = 0.201).

DISCUSSION

Women are disproportionately underrepresented in stroke trials relative to the burden of disease in the population. Clear guidance and effective implementation strategies are required to improve the inclusion of women and thus broader knowledge of the impact of interventions in clinical trials.

Sex and Gender in COVID-19 Vaccine Research: Substantial Evidence Gaps Remain

Since the start of the COVID-19 pandemic there has been a global call for sex/gender-disaggregated data to be made available, which has uncovered important findings about COVID-19 testing, incidence, severity, hospitalisations, and deaths. This mini review scopes the evidence base for efficacy, effectiveness, and safety of COVID-19 vaccines from both experimental and observational research, and asks whether (1) women and men were equally recruited and represented in vaccine research, (2) the outcomes of studies were presented or analysed by sex and/or gender, and (3) there is evidence of sex and/or gender differences in outcomes. Following a PubMed search, 41 articles were eligible for inclusion, including seven randomised controlled trials (RCTs), 11 cohort studies, eight cross-sectional surveys, eight routine surveillance studies, and seven case series. Overall, the RCTs contained equal representation of women and men; however, the observational studies contained a higher percentage of women. Of 10 studies with efficacy data, only three (30%) presented sex/gender-disaggregated results. Safety data was included in 35 studies and only 12 (34%) of these presented data by sex/gender. For those that did present disaggregated data, overall, the majority of participants reporting adverse events were women. There is a paucity of reporting and analysis of COVID-19 vaccine data by sex/gender. Research should be designed in a gender-sensitive way to present and, where possible analyse, data by sex/gender to ensure that there is a robust and specific evidence base of efficacy and safety data to assist in building public confidence and promote high vaccine coverage.

Sex Differences in Cerebral Small Vessel Disease: A Systematic Review and Meta-Analysis

Background: Cerebral small vessel disease (SVD) is a common cause of stroke, mild cognitive impairment, dementia and physical impairments. Differences in SVD incidence or severity between males and females are unknown. We assessed sex differences in SVD by assessing the male-to-female ratio (M:F) of recruited participants and incidence of SVD, risk factor presence, distribution, and severity of SVD features. Methods: We assessed four recent systematic reviews on SVD and performed a supplementary search of MEDLINE to identify studies reporting M:F ratio in covert, stroke, or cognitive SVD presentations (registered protocol: CRD42020193995). We meta-analyzed differences in sex ratios across time, countries, SVD severity and presentations, age and risk factors for SVD. Results: Amongst 123 relevant studies (n = 36,910 participants) including 53 community-based, 67 hospital-based and three mixed studies published between 1989 and 2020, more males were recruited in hospital-based than in community-based studies [M:F = 1.16 (0.70) vs. M:F = 0.79 (0.35), respectively; p < 0.001]. More males had moderate to severe SVD [M:F = 1.08 (0.81) vs. M:F = 0.82 (0.47) in healthy to mild SVD; p < 0.001], and stroke presentations where M:F was 1.67 (0.53). M:F did not differ for recent (2015-2020) vs. pre-2015 publications, by geographical region, or age. There were insufficient sex-stratified data to explore M:F and risk factors for SVD. Conclusions: Our results highlight differences in male-to-female ratios in SVD severity and amongst those presenting with stroke that have important clinical and translational implications. Future SVD research should report participant demographics, risk factors and outcomes separately for males and females. Systematic Review Registration: [PROSPERO], identifier [CRD42020193995].

Sex Disparities in Enrollment in Recent Randomized Clinical Trials of Acute Stroke: A Meta-analysis

Importance

The underenrollment of women in randomized clinical trials represents a threat to the validity of the evidence supporting clinical guidelines and potential disparities in access to novel treatments.

Objective

To determine whether women were underenrolled in contemporary randomized clinical trials of acute stroke therapies published in 9 major journals after accounting for their representation in underlying stroke populations.

Data Sources

MEDLINE was searched for acute stroke therapeutic trials published between January 1, 2010, and June 11, 2020.

Study Selection

Eligible articles reported the results of a phase 2 or 3 randomized clinical trial that enrolled patients with stroke and/or transient ischemic attack and examined a therapeutic intervention initiated within 1 month of onset.

Data Extraction

Data extraction was performed by 2 independent authors in duplicate. Individual trials were matched to estimates of the proportion of women in underlying stroke populations using the Global Burden of Disease database.

Main Outcomes and Measures

The primary outcome was the enrollment disparity difference (EDD), the absolute difference between the proportion of trial participants who were women and the proportion of strokes in the underlying disease populations that occurred in women. Random-effects meta-analyses of the EDD were performed, and multivariable metaregression was used to explore the associations of trial eligibility criteria with disparity estimates.

Results

The search returned 1529 results, and 115 trials (7.5%) met inclusion criteria. Of 121 105 randomized patients for whom sex was reported, 52 522 (43.4%) were women. The random-effects summary EDD was -0.053 (95% CI, -0.065 to -0.040), indicating that women were underenrolled by 5.3 percentage points. This disparity persisted across virtually all geographic regions, intervention types, and stroke types, apart from subarachnoid hemorrhage (0.117 [95% CI, 0.084 to 0.150]). When subarachnoid hemorrhage trials were excluded, the summary EDD was -0.067 (95% CI, -0.078 to -0.057). In the multivariable metaregression analysis, an upper age limit of 80 years as an eligibility criterion was associated with a 6-percentage point decrease in the enrollment of women.

Conclusions and Relevance

Further research is needed to understand the causes of the underenrollment of women in acute stroke trials. However, to maximize representation, investigators should avoid imposing age limits on enrollment.