WASHINGTON: A recent study has found that there are marked gender differences in what drives blood pressure in middle-age and adulthood, suggesting the need for gender-specific treatments for hypertension.
"Blood pressure is determined mainly by three factors: heart rate; stroke volume, which is the volume of blood pumped by the heart; and the resistance to blood flow through the vessels, called total peripheral resistance. An increase in any one of the three factors can lead to an increase in blood pressure," said study author Catriona Syme from The Hospital for Sick Children (SickKids) in Toronto, Ontario, Canada.
"The key takeaway from this study is that, for young and middle-aged women, stroke volume was the main determinant of blood pressure, while, in men, vascular resistance was the main determinant of blood pressure," Syme noted.
Syme and colleagues studied 1,347 Canadians from the Saguenay Youth Study, including 911 adolescents and 426 adults ages 36 to 65 years. The researchers used a device that measures beat-by-beat blood pressure and the underlying forces of heart rate, stroke volume and total peripheral resistance. In the approximately hour-long protocol, they measured these variables at rest, and during posture changes and a mental stressor - all designed to mimic daily life activities, according to Syme.
Researchers found that in females, stroke volume explains 55 percent of the variance in systolic blood pressure (the top number in a blood pressure reading), versus only 35 percent in males.
In males, the major determinant of systolic blood pressure was total peripheral resistance, which explained 47 percent of the variance, versus only 30 percent in females.
These gender differences were seen across most of the 52-minute protocol, being most prominent during standing and least evident during mental stress, according to the abstract.
While current treatment recommendations for hypertension do not differ by gender across all ages, this study suggested potential benefits to prescribing blood pressure-lowering medications with consideration for gender differences in the underlying physiology of elevated blood pressure in young and middle-aged adults.
The research has been presented at the American Heart Association (AHA) Council on Hypertension, AHA Council on Kidney in Cardiovascular Disease, American Society of Hypertension Joint Scientific Sessions 2017, in San Francisco.