Sex and Gender-based Analysis of this topic
Definition
Blood pressure is the measure of the pressure or force of blood against the walls of the arteries in the body. It is typically reported as a pair of high and low numbers. The top number (systolic number) represents the pressure when your heart contracts and pushes blood out; the bottom number (diastolic number) represents the lowest pressure when the heart relaxes between beats [1]. Normal blood pressure is below 120/80 mm Hg (expressed as millimeters in mercury), while blood pressure consistently above 140/90 mm Hg is considered high. High blood pressure (hypertension) can damage the kidneys, blood vessels, and strain the heart leading to a weak heart or cardiovascular disease. Continuous, very high blood pressure can cause blood vessels in the brain to weaken to the point where they may burst resulting in a stroke. High blood pressure may be caused by excessive weight, being physically inactive, heavy alcohol use, and/or excessive salt intake [2]. However, in many cases the exact cause of hypertension is not known. Hypertension is a major, independent risk factor for heart disease. Heart disease is the number one cause of death for women in Canada [3] and more women than men report having high blood pressure [2].
Sex Issues
After menopause, women’s rates of coronary artery disease increase, which may be due to increases in cholesterol, fat around the abdomen, and high blood pressure as well as decreases in estrogen levels that previously protected women’s heart and blood vessels [4-5].
Women with high blood pressure and diabetes are at greater risk for developing heart failure and stroke than men with these risk factors. Higher stroke rates may be related to women’s greater life expectancy and high rates of stroke in older age groups. Adult onset diabetes is a risk factor for developing high blood pressure [2] and the risk for adult onset diabetes is the highest for women between the ages of 20 and 34 [6]. Approximately two thirds of Canadians with hypertension and diabetes have uncontrolled hypertension [7].
Hypertension during pregnancy poses a number of health risks for women. Pre-eclampsia is high blood pressure that can affect pregnant women after the 20-week mark [8]. Pre-eclampsia can harm the liver, kidneys, or brain and can prevent the fetus from getting enough blood and oxygen. Based on data from CIHI, women with hypertension and/or diabetes are twice as likely to give birth to a small-for-gestational age (SGA) baby [9]. Women with gestational diabetes are at risk for developing Type 2 diabetes, which may further increase their risk of hypertension [10].
Gender Issues
High blood pressure is often referred to as a silent killer because there are few signs or symptoms in men or women. However, middle-aged women are often not screened or diagnosed properly. This may be because high blood pressure is related to heart disease, which continues to be considered a man’s disease. Many Canadian women are unaware that heart disease is the number one cause of death in women [3]. When women do present with cardiovascular concerns, they are less likely to receive additional procedures such as angiography, which puts women at risk of further complications due to cardiovascular disease [11]. This lack of screening is troublesome given that many women between the ages of 20 and 39 have their blood pressure checked regularly at physician visits for contraception and prenatal care [2].
Diversity
High blood pressure is more common among individuals with lower and lower-middle incomes [2]. Though the Heart and Stroke Foundation of Canada recommends lifestyle changes such as eating healthy and increasing physical activity levels, women with lower incomes may not have the resources or time to follow these recommendations. Further, women with low incomes are more likely to work part-time jobs that do not include medical benefits [12] and thus, may not be able to afford medications that could control high blood pressure.
In British Columbia, Aboriginal First Nations’ high blood pressure rates are higher compared to the general population [13], which may be related to being overweight or obese and higher rates of diabetes [14, 15]. In one sample from Northwestern Ontario, Aboriginal women’s blood pressure was 2.5 times higher than non-Aboriginal women [16].
Critique
We currently lack population-wide physical and biochemical measures of cardiovascular risk. Most Canadian health surveys rely on self-reported height and weight to identify individuals who are overweight and at risk for high blood pressure, which may not be accurate. Heart Health Surveys, which included biomedical measures, have not been repeated resulting in a lack of information on high blood pressure screening. Additional surveillance that includes biomedical measurement would also increase cross-Canada comparison of hypertension statistics. Gender-specific risk factors, such as physical inactivity, education, and low income, need to be further examined to understand how they may contribute to high blood pressure.