Untreated Isolated Sytolic Hypertension among Middle-Aged and Old Adults in the United States: Trends in the Prevalence by Demographic Factors During 1999-2010.

Isolated systolic hypertension (ISH) predominates hemodynamic hypertension subtypes and becomes a significant factor for cardiovascular and renal outcomes in middle-aged and old adults. The prevalence and changes of untreated ISH have not been fully investigated in this population. A total of 12,097 participants aged ≥40 years were selected from the National Health and Nutrition Examination Survey 1999-2010. The overall prevalence of untreated ISH was 15.2%. The prevalence decreased significantly from 16.8% in 1999-2004 to 13.5% in 2005-2010. Females, non-Hispanic blacks, and adults with low education had higher prevalence of untreated ISH than males, non-Hispanic whites, and adults with high education, respectively. Compared with 1999-2004, the prevalence of untreated ISH in 2005-2010 reduced in old adults (28.0% versus 37.7%), females (14.3% versus 19.5%), and non-Hispanic whites (12.7% versus 16.2%). The stratified prevalence of untreated ISH decreased in 2005-2010 in non-Hispanic white females (12.8% versus 18.6%) and females who did not attend college (16.9% versus 21.8%). Untreated ISH is more prevalent in old and female subjects, and significant improvements in these groups suggest that public health measures or changes are in the right direction.