Over the past two decades, the number of strokes in the United States has been steadily declining. While this is welcomed and good news, it primarily pertains to a faster reduction in stroke rates for men but not for women. This report is from new research published in the online issue of Neurology which found that during their study period, rates of stroke for men declined but rates of stroke for women remained the same.
This new study, led by a group of researchers from Brown University, University of Cincinnati, Indiana University, and Baylor College of Medicine, collected data on 1.3 million adults living in a five-county area capturing southwest Ohio and northern Kentucky between 1993 and 2010. Records from hospitals, clinics and coroner’s reports were used to identify how many people had a first stroke during four one-year periods, spaced approximately five years apart.
Their investigation found that while the stroke rate for men declined significantly during the 15-year study period, for women there was no significant difference.
Specifically discovered was that among more than 7,700 strokes, 57 percent occurred in women. The average age of a first stroke for women is 72 while in men the average age for first stroke is 68. After standardizing their findings with the U. S. Census data, researchers found that for men, the overall rate of strokes went from 268 strokes per 100,000 at the start of the study to 192 per 100,000 at the end of the study. For women, the rate of strokes went from 217 strokes per 100,000 in 1993 to 198 per 100,000 in 2010 which was not a statistically significant reduction.
Another finding from the study was that the rates of reduction of stroke in men were mainly driven by a decrease in ischemic strokes. Ischemic stroke, the most common type of stroke, is usually caused by a blood clot that blocks or plugs a blood vessel in the brain. However hemorrhagic strokes, caused by bleeding in the brain, remained stable for both men and women.
According to the U.S. Centers for Disease Control and Prevention, stroke has dropped to the fifth leading cause of death for men but remains the fourth leading cause of death for women. Historically, the risk of strokes in women has been lower than in men, whether before menopause and even after menopause. These findings are concerning for doctors as to why American women are not seeing the same benefits from stroke prevention.
There are several possible reasons why the results from this study show a discrepancy of stroke rates declining in men but not women. One reason might be that medical providers are not recognizing the increased risk of stroke in women as they tend to have atypical symptoms of stroke when compared to men. This may be leading to physicians not being as aggressive in counseling women about their risk factors and the early signs of stroke as they do for men. Another consideration is the biological differences in how risk factors lead to stroke in men and women.
Also, strategies used to prevent stroke may not be as effective in women as in men. Risk factors associated with stroke such as high blood pressure, high cholesterol and diabetes may be more severe or not as well-controlled in women. Prior studies have shown that women are less likely to have their blood pressure at goal when compared to men.
What is known is that risk factors for stroke are on the rise. High blood pressure, high cholesterol, and diabetes continue to escalate as the U.S. population ages. With these known facts and from the results of this study, more research needs to occur on safeguarding and reducing the risk of stroke in women.