Ischemic stroke rates are higher in young women than in young men
Young women appear to be at higher risk of ischemic stroke than young men, according to a new systematic review of studies on this topic.
The review included 19 studies that reported on the incidence of stroke by sex in young adults and found that overall in young adults aged 18 to 35 there were 44% more women with ischemic stroke than men.
This gap narrowed in the 35-45 age group, for which there was conflicting evidence whether more men or women have ischemic strokes.
“A claim that young women may be disproportionately at risk for ischemic stroke represents a significant departure from our current scientific understanding and may have important implications for the etiology of ischemic stroke in young adults,” the authors note. .
“One of the take-home messages from this study is that stroke occurs at all ages, including young adults, even if they don’t have traditional risk factors,” study co-author Sharon N. Poisson, MD, associate professor of neurology at the University of Colorado Anschutz Medical Campus in Denver, said lecoeur.org | Medscape Cardiology.
“If a young person has focal neurological symptoms, the possibility of a stroke should not be ruled out simply because they do not fit the typical profile of a stroke patient. We need greater education of the population so that young people – including young women – can have a stroke, and that it is essential to act quickly to call the emergency services,” she said.
The study was published online January 24 in the journal Stroke as part of a special “Go Red for Women” issue.
The researchers note that historically, men were believed to have a higher incidence of stroke in all age groups until very old age. However, recent evidence focusing on the young adult age group has indicated that there are more young women (aged 18-45) with ischemic strokes than young men, suggesting that young women may be disproportionately at risk compared to their male counterparts.
Highlighting that a better understanding of these gender differences is important for implementing strategies that can more effectively prevent and treat stroke in this age group, the researchers conducted the present review to synthesize the updated evidence. .
They searched PubMed from January 2008 to July 2021 for relevant population-based studies reporting stroke incidence by sex or sex-specific incidence rate ratios in young adults aged 45 and younger. A statistical summary was performed to estimate the difference between the sexes by age group (≤ 35, 35-45 and ≤ 45 years) and type of stroke.
They found 19 relevant studies, three of which reported overlapping data, with a total of 69,793 young adults (33,775 women and 36,018 men).
Nine studies did not show a statistically significant gender difference in young adults ≤ 45 years. Three studies found higher rates of ischemic stroke in men in young adults ≥ 30 to 35 years old. Four studies showed more women with ischemic strokes in young adults ≤ 35 years old.
Overall, there was an effect of a significantly higher incidence of ischemic stroke in women younger than 35, with an incidence rate ratio (IRR) of 1.44. In the 35-45 year age group, there was a non-significant gender difference in the rate of ischemic stroke, with a slight trend towards a higher incidence in females (IRR, 1.08).
“In this study, the gender difference was not clear in the 35-45 age group. But in the over 45 age group, we know that men are at risk of higher stroke than women, which is likely related to a higher level of atherosclerotic risk factors,” Poisson commented.
“Interpreting data on strokes in young people is difficult because strokes are not that common in this population,” she said. “Combining multiple studies helps, but it also introduces a lot of variability, so we have to interpret these results with some caution. However, these are certainly intriguing data and suggest that something interesting might be going on in young adults,” she added. “These observations give us a first hint that we need to investigate this question further.”
The study did not examine the possible mechanisms behind the results, as the current data comes from administrative datasets which are limited in terms of the information collected.
But Poisson noted that the traditional risk factors for stroke are high blood pressure and the usual atherosclerotic factors such as high cholesterol.
“These are normally more common in men than in women, and myocardial infarction is more common in young men than in young women. But the observation that young women may have a higher risk of stroke that young men suggests something different may be going on.” in the mechanism of stroke.”
She pointed out that women have unique risk factors for stroke, including the use of oral contraceptives, pregnancy and the postpartum period, especially preeclampsia during pregnancy. Additionally, migraine, particularly migraine with aura, is associated with an increased risk of stroke, and migraine is more common in young women than in young men.
“We don’t fully understand the role of these risk factors, but they may contribute to the results we found,” Poisson commented. “The role of estrogen in stroke is complicated. While estrogen is generally thought to protect against risk factors for atherosclerosis, it also increases the risk of clotting, so high estrogen states like pregnancy increase the risk of stroke,” she added.
To better understand what is happening, prospectively collected clinical data on younger patients who have had a stroke are needed. Some such studies are underway, but a concerted effort to do so in a large, multicenter registry would be desirable, Poisson said.
She noted that the presentation of stroke in young people would be similar to that of the older population, with the newest acronym to help recognize stroke symptoms being “BE FAST” – balance, eyes (vision ), face (sagging), arm, speech (garbled), time (quickly call emergency services).
Call for more women in clinical trials
In an accompanying commentary, Cheryl Bushnell, MD, professor of neurology at Wake Forest School of Medicine, Winston Salem, North Carolina, and Moira Kapral, MD, professor of medicine and health policy at the University of Toronto , Canada, say these findings support the need for further study to understand and address the causes and risk factors for stroke in young women.
However, they highlight that the representation and reporting of women in acute stroke clinical trials continue to be suboptimal, and they call for better integration of sex and gender into the design, analysis and reporting. interpretation of studies, which they say is critical to producing research that is broadly generalizable and applicable to different populations.
Co-author Stacey L. Daugherty, MD, is funded by the National Institutes of Health. Poisson and Kapral did not disclose any relevant financial relationship. Bushnell reports a stake in Care Directions, LLC.
Stroke. Published online January 24, 2022. Full Text, Editorial
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