Factors associated with antihypertensive monotherapy among US adults with treated hypertension and uncontrolled blood pressure overall and by race/ethnicity, National Health and Nutrition Examination Survey 2013-2018

Background: Treating hypertension with antihypertensive medications combinations, rather than one medication (ie, monotherapy), is underused in the United States, particularly in certain race/ethnic groups. Identifying factors associated with monotherapy use despite uncontrolled blood pressure (BP) overall and within race/ethnic groups may elucidate intervention targets in under-treated populations. Methods: Cross-sectional analysis of National Health and Nutrition Examination Surveys (NHANES; 2013-2014 through 2017-2018). We included participants age ≥20 years with hypertension, taking at least one antihypertensive medication, and uncontrolled BP (systolic BP [SBP] ≥ 140 mmHg or diastolic BP [DBP] ≥ 90 mmHg). Demographic, clinical, and healthcare-access factors associated with antihypertensive monotherapy were determined using multivariable-adjusted Poisson regression. Results: Among 1,597 participants with hypertension and uncontrolled BP, age- and sex- adjusted prevalence of monotherapy was 42.6% overall, 45.4% among non-Hispanic White, 31.9% among non-Hispanic Black, 39.6% among Hispanic, and 50.9% among non-Hispanic Asian adults. Overall, higher SBP was associated with higher monotherapy use, while older age, having a healthcare visit in the previous year, higher body mass index, and having heart failure were associated with lower monotherapy use. Conclusion: Clinical and healthcare-access factors, including a healthcare visit within the previous year and co-morbid conditions were associated with a higher likelihood of combination antihypertensive therapy.