Sex Differences in Hypertension: A Question worth Asking?

Abstract

Hypertension is a complex disorder involving multiple organ systems and the primarily modiiiable risk factor for heart disease, which is the leading cause of death among both men and women in the World. Although both men and women develop hypertension, distinct gender differences in the incidence and severity of hypertension are well established where men have a higher incidence of hypertension compared with women of the same age until the sixth decade of life [1,2]. Despite gender differences in human hypertension, the treatment guidelines do not differ by gender [3]. Even if the causes of hypertension are complex and are related to genetic factors, lifestyle, diet structure, and environmental factors including air pollution [4], coupled with the potential determinants of hypertension, sex differences in hypertension-which exist in human populations-are attributed to both biological and behavioural factors. The biological factors include sex hormones, chromosomal differences, and other biological sex differences that are protective against hypertension in women. These factors become prominent in adolescence and persist through adulthood until women reach menopause. Behavioural risk factors for hypertension include high body mass index, smoking, and low physical activity. The recent National Health and Nutrition Examination Survey study examined age-adjusted awareness, treatment, and blood pressure control rates among hypertensive men and women from 2003 to 2004 through 2011 to 2012 [1] with encouraging results. Awareness of hypertension increased in both men and women during this time period, with the greatest increase in awareness reported in women. Although women were less aware of their hypertension at the beginning of the study, they surpassed men's awareness by the end of the study. In addition, the percent of individuals treated for their hypertension increased from 2003 to 2012, and again this increase was greater in women [1]. Most importantly, however, the increase in treatment was associated with an increase in the percent of hypertensive patients who achieved blood pressure controlled to the recommended levels from ≈43% to 49% in men and from ≈37% to 56% among women [1]. Although this reelects a large improvement in the numbers of individuals with controlled blood pressure, this still leaves almost half of the hypertensive population at increased risk for adverse cardiovascular events [1]. The authors further examined the numbers of men and women with optimal blood pressure, prehypertension, stage I hypertension, and stage II hypertension over the same