Editorial
Sex differences and stroke prevention International Women’s Day was fast approaching as this issue of The Lancet Neurology went to press, so it seemed appropriate to celebrate the publication of the first set of guidelines to focus exclusively on the prevention of stroke in women. The guidelines from the American Heart Association (AHA) and the American Stroke Association identify stroke risk factors that are unique to or more common in women, or that preferentially increase risk in women compared with men, and provide evidence-based recommendations for stroke prevention across the lifespan. Women have a higher lifetime risk of stroke than men and stroke mortality is higher in women than in men in high-income countries. In the USA, 76 769 (60%) of the 128 842 deaths related to stroke in 2009 occurred in women. These facts are often attributed to the longer life expectancy of women. As the population ages, the prevalence of stroke survivors is expected to increase, especially among older women. Poorer outcomes in women have been reported and could add to the anticipated increase in the burden of stroke. There is a pressing need for earlier identification of women at risk of stroke so that effective prevention strategies can be initiated. Education of younger women about stroke risk and prevention at different life stages will be key to this goal, and the new guidelines are an important step in the right direction. Various factors that differ between women and men— among them genetic, hormonal, reproductive, social, and lifestyle factors—can affect stroke risk or recovery after stroke. Although other primary and secondary stroke prevention guidelines address issues specific to women, the new guidelines are the first to provide a detailed appraisal of the evidence on stroke risk related to pregnancy, oral contraceptives, menopause, and hormone therapy. For example, the guidelines highlight the serious short-term risks associated with hypertensive disorders of pregnancy, including preeclampsia, and the long-term risk of stroke in women with a history of pregnancy complications. Migraine with aura, atrial fibrillation, diabetes mellitus, and depression are among the stroke risk factors identified as being more common in women than in men. Despite growing awareness of the factors that affect stroke risk in women, uncertainty has persisted among www.thelancet.com/neurology Vol 13 April 2014
health-care professionals surrounding the screening, testing, and treatment of women in relation to these issues, and many will welcome the clear guidance on risk reduction and stroke prevention. But there will doubtless be some points of controversy. The guidelines go against the advice of the American Congress of Obstetricians and Gynecologists, for instance, by recommending that antihypertensive medication be considered for pregnant women with moderately high blood pressure (150–159 mm Hg/100–109 mm Hg). The recommended use of aspirin for the primary prevention of stroke follows other AHA guidance, but has been the subject of debate since a meta-analysis by the Antithrombotic Trialists’ Collaboration called into question the benefit in women. And the lack of evidence to support some proposed prevention strategies—the use of treatments to reduce migraine frequency, for example, in women who have migraine with aura—leaves best practice open to question. The new guidelines acknowledge gaps in the evidence and aim to draw attention to areas of uncertainty. Many trials have not included sufficient numbers of women or have not undertaken sexspecific analyses to identify differences in the effectiveness of various prevention strategies. Priorities for future research include the questions of whether sex differences exist in the effectiveness of antihypertensive drugs, why blood pressure control declines with age in women, and which lifestyle changes or drugs are most effective for the prevention of hypertension and stroke in women with a history of pre-eclampsia. Epidemiological studies should provide more data on stroke subtypes, especially haemorrhagic stroke, and on outcomes after stroke, in addition to accounting for sex and age. The new guidelines focus primarily on stroke risk and prevention in women in the USA and other highincome countries. More data are needed on the factors that affect stroke risk and stroke outcomes in women in low-income and middle-income countries so that their needs can also be addressed. Further defining stroke risk and the burden of stroke by sex, age, race, ethnic group, and geographical location will help to reduce health disparities within and across geographical regions for all those at risk of stroke. ■ The Lancet Neurology
For more on International Women’s Day see http://www. internationalwomensday.com/ For the AHA/ASA guidelines see Stroke 2014; published online Feb 6. DOI:10.1161/01. str.0000442009.06663.48 For more on sex differences in stroke see Review Lancet Neurol 2008; 7: 915–26 For more on the menopause and hormone therapy see Review Lancet Neurol 2012; 11: 82–91 For results from the Antithrombotic Trialists’ Collaboration see Articles Lancet 2009; 373: 1849–60 For more on the global and regional burden of stroke see Articles Lancet 2014; 383: 245–55
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Sex differences and stroke prevention International Women’s Day was fast approaching as this issue of The Lancet Neurology went to press, so it seemed appropriate to celebrate the publication of the first set of guidelines to focus exclusively on the prevention of stroke in women. The guidelines from the American Heart Association (AHA) and the American Stroke Association identify stroke risk factors that are unique to or more common in women, or that preferentially increase risk in women compared with men, and provide evidence-based recommendations for stroke prevention across the lifespan. Women have a higher lifetime risk of stroke than men and stroke mortality is higher in women than in men in high-income countries. In the USA, 76 769 (60%) of the 128 842 deaths related to stroke in 2009 occurred in women. These facts are often attributed to the longer life expectancy of women. As the population ages, the prevalence of stroke survivors is expected to increase, especially among older women. Poorer outcomes in women have been reported and could add to the anticipated increase in the burden of stroke. There is a pressing need for earlier identification of women at risk of stroke so that effective prevention strategies can be initiated. Education of younger women about stroke risk and prevention at different life stages will be key to this goal, and the new guidelines are an important step in the right direction. Various factors that differ between women and men— among them genetic, hormonal, reproductive, social, and lifestyle factors—can affect stroke risk or recovery after stroke. Although other primary and secondary stroke prevention guidelines address issues specific to women, the new guidelines are the first to provide a detailed appraisal of the evidence on stroke risk related to pregnancy, oral contraceptives, menopause, and hormone therapy. For example, the guidelines highlight the serious short-term risks associated with hypertensive disorders of pregnancy, including preeclampsia, and the long-term risk of stroke in women with a history of pregnancy complications. Migraine with aura, atrial fibrillation, diabetes mellitus, and depression are among the stroke risk factors identified as being more common in women than in men. Despite growing awareness of the factors that affect stroke risk in women, uncertainty has persisted among www.thelancet.com/neurology Vol 13 April 2014
health-care professionals surrounding the screening, testing, and treatment of women in relation to these issues, and many will welcome the clear guidance on risk reduction and stroke prevention. But there will doubtless be some points of controversy. The guidelines go against the advice of the American Congress of Obstetricians and Gynecologists, for instance, by recommending that antihypertensive medication be considered for pregnant women with moderately high blood pressure (150–159 mm Hg/100–109 mm Hg). The recommended use of aspirin for the primary prevention of stroke follows other AHA guidance, but has been the subject of debate since a meta-analysis by the Antithrombotic Trialists’ Collaboration called into question the benefit in women. And the lack of evidence to support some proposed prevention strategies—the use of treatments to reduce migraine frequency, for example, in women who have migraine with aura—leaves best practice open to question. The new guidelines acknowledge gaps in the evidence and aim to draw attention to areas of uncertainty. Many trials have not included sufficient numbers of women or have not undertaken sexspecific analyses to identify differences in the effectiveness of various prevention strategies. Priorities for future research include the questions of whether sex differences exist in the effectiveness of antihypertensive drugs, why blood pressure control declines with age in women, and which lifestyle changes or drugs are most effective for the prevention of hypertension and stroke in women with a history of pre-eclampsia. Epidemiological studies should provide more data on stroke subtypes, especially haemorrhagic stroke, and on outcomes after stroke, in addition to accounting for sex and age. The new guidelines focus primarily on stroke risk and prevention in women in the USA and other highincome countries. More data are needed on the factors that affect stroke risk and stroke outcomes in women in low-income and middle-income countries so that their needs can also be addressed. Further defining stroke risk and the burden of stroke by sex, age, race, ethnic group, and geographical location will help to reduce health disparities within and across geographical regions for all those at risk of stroke. ■ The Lancet Neurology
For more on International Women’s Day see http://www. internationalwomensday.com/ For the AHA/ASA guidelines see Stroke 2014; published online Feb 6. DOI:10.1161/01. str.0000442009.06663.48 For more on sex differences in stroke see Review Lancet Neurol 2008; 7: 915–26 For more on the menopause and hormone therapy see Review Lancet Neurol 2012; 11: 82–91 For results from the Antithrombotic Trialists’ Collaboration see Articles Lancet 2009; 373: 1849–60 For more on the global and regional burden of stroke see Articles Lancet 2014; 383: 245–55
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![[Sex and gender differences in cardiovascular prevention].](/assets/img/hold.png)
