Prevalence and trends of isolated systolic hypertension among untreated adults in the United States

•Examining the prevalence and changes of isolated systolic hypertension (ISH) among untreated adults.•The prevalence of untreated ISH declined significantly from 1999–2004 to 2005–2010.•The prevalence of ISH in 2005–2010 decreased significantly in the elderly, females, and non–Hispanic Whites.•ISH improved in older non–Hispanic whites and blacks, non–Hispanic white females, older individuals with a college education or above, and females with a high school education or below.

The prevalence and long–term trends of isolated systolic hypertension (ISH) among untreated adults have not been reported. Data from 24,653 participants aged ≥18 years were selected from the National Health and Nutrition Examination Survey 1999–2010. The prevalence and 95% confidence intervals (CIs) of untreated ISH were estimated by conducting the independent survey t–test. The prevalence of untreated ISH was 9.4% and decreased from 10.3% in 1999–2004 to 8.5% in 2005–2010 (P = .00248). Old persons, females, and non–Hispanic blacks had higher prevalence of untreated ISH. Compared with 1999–2004, the prevalence of untreated ISH in 2005–2010 decreased among older (33.6%; 95% CI, 30.9%–36.3% vs. 25.1%; 95% CI, 22.7%–27.5%) and female individuals (8.3%; 95% CI, 7.5–9.2% vs. 11.4%; 95% CI, 10.4–12.3%). The stratified prevalence of untreated ISH declined in 2005–2010 (vs. 1999–2004) for older non–Hispanic whites (24.6% vs. 32.8%; P < .0001) and blacks (27.7% vs. 40.8%; P = .0013), non–Hispanic white females (7.5% vs. 10.8%; P < .0001), older individuals with higher education (21.0% vs. 30.6%; P = .0024), and females with lower education (10.1% vs. 13.1%; P = .006). Untreated ISH is more prevalent in older adults and females. Significant decreases in untreated ISH prevalence over time among these groups suggest that public health measures and/or treatment patterns are trending in the right direction.