Abstract
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.