Height May Explain Sex Differences in Systolic Blood Pressure in Older Adults

Differences in height may contribute to higher systolic blood pressure values and lower hypertension control rates in older women than men. National Health and Nutrition Examination Surveys cross-sectional data from 2005 to 2006 through 2017 to 2020 were analyzed on women (n=1682) and men (n=1468), aged ≥75 years with hypertension (systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg or antihypertensive pharmacotherapy). The association of height and sociobiological variables (body mass index, education, income, chronic kidney disease, cardiovascular disease, diabetes, statin therapy) with sex differences in systolic blood pressure was assessed by multivariable linear regression, and their association with hypertension control was assessed by multivariable logistic regression. Data are presented as mean (95% CI). Systolic blood pressure was higher in older women than men (145.8 mm Hg [144.5-147.1] versus 139.3 mm Hg [138.1-140.6]; P<0.001). Women were shorter than men (1.57 [1.56-1.57] versus 1.71 [1.71-1.72] meters; P<0.0001). Adjusting for height eliminated sex differences in systolic blood pressure (6.4 mm Hg [5.0-7.9] unadjusted versus -0.6 mm Hg [-3.1-1.9] height adjusted), whereas adjusting for sociobiological variables did not (5.0 mm Hg [3.4-6.6]). Hypertension control to <140/<90 mm Hg was less frequent in women than men (38.0% [35.2-40.7] versus 47.1% [43.7-50.5]; P<0.001). The lower odds ratio for hypertension control in women than men (0.69 [0.60-0.79] unadjusted) was eliminated after adjusting for height (1.12 [0.91-1.36]), but not after adjusting for sociobiological variables (0.73 [0.63-0.85]). Shorter stature in older women than men is associated with higher systolic blood pressure and lesser hypertension control in older women.