Use trends of chlorthalidone and hydrochlorothiazide among United States adults with hypertension: National Health and Nutrition Examination Survey 2009-2018

Objectives: To estimate the national prevalence of chlorthalidone and hydrochlorothiazide use among adults diagnosed with hypertension by sociodemographic subgroup, healthcare access status, and clinical factors. Methods: Data was extracted from the National Health and Nutrition Examination Survey for 20092010 through 20172018 survey waves. Patients at least 20 years old, diagnosed with hypertension, and on hydrochlorothiazide or chlorthalidone were included. Uni-variable logistic regression models estimated the odds of being on chlorthalidone compared with hydrochlorothiazide use by sociodemographic and clinical factors. Analyses were adjusted for multi-stage complex survey design and are nationally representative. Results: Two thousand five hundred and eighty-five participants were included with 95.2% participants using hydrochlorothiazide and 4.8% using chlorthalidone. Participants over 65 years were more likely to be on chlorthalidone compared with younger counterparts [odds ratio (OR) 1.8; 95% confidence interval (CI) 1.122.88]. Participants with hypokalemia (OR 2.62; 95% CI 1.564.42) or hyponatremia [OR 2.298; 95% CI 1.234.30) were more likely to be using chlorthalidone compared with patients with normal levels. Conclusion: Chlorthalidone, a potent and effective first-line antihypertensive agent and thoroughly studied thiazide diuretic with substantial cardiovascular benefits, continues to be underutilized in patients with hypertension. Findings demonstrated that individuals receiving chlorthalidone were more likely to be 65 years or older and to experience hyponatremia or hypokalemia. Sociodemographic factors, healthcare access and use, clinical factors, and medical conditions did not appear to sway the choice in thiazide diuretic use.