Predominance of isolated systolic hypertension among middle-aged and elderly US hypertensives - Analysis based on National Health and Nutrition Examination Survey (NHANES) III

The purpose of the present study was to examine patterns of systolic and di astolic hypertension by age in the nationally representative National Healt h and Nutrition Examination Survey (NHANES) III and to determine when treat ment and control efforts should be recommended. Percentage distribution of 3 blood pressure subtypes (isolated systolic hypertension, combined systoli c/diastolic hypertension, and isolated diastolic hypertension) was categori zed for uncontrolled hypertension (untreated and inadequately treated) in 2 age groups (ages <50 and <greater than or equal to>50 years). Overall, iso lated systolic hypertension was the most frequent subtype of uncontrolled h ypertension (65%). Most subjects with hypertension (74%) were greater than or equal to 50 years of age, and of this untreated older group, nearly all (94%) were accurately staged by systolic blood pressure alone, in contrast to subjects in the untreated younger group, who were best staged by diastol ic blood pressure. Furthermore, most subjects (80%) in the older untreated and the inadequately treated groups had isolated systolic hypertension and required a greater reduction in systolic blood pressure than in the younger groups (-13.3 and -16.5 mm Hg versus -6.8 and -6.1 mm Hg, respectively; P = 0.0001) to attain a systolic blood pressure treatment goal of <140 mm Hg. Contrary to previous perceptions, isolated systolic hypertension was the m ajority subtype of uncontrolled hypertension in subjects of ages 50 to 59 y ears, comprised 87% frequency for subjects in the sixth decade of life, and required greater reduction in systolic blood pressure in these subjects to reach treatment goal compared with subjects in the younger group. Better a wareness of this middle-aged and older high-risk group and more aggressive antihypertensive therapy are necessary to address this treatment gap.