Comparison of Treatment Therapies for Hypertensive Patients

Cincinnati—Hypertension affects >76 million adults in the United States, making it one of the most common chronic diseases. Over the long term, uncontrolled hypertension is associated with risk for cardiovascular diseases and complications in other organs and systems, including myocardial infarction, heart failure, stroke, and kidney disease.

Estimated direct healthcare costs associated with hypertension in 2010 were $54.9 billion.

Most hypertensive patients are prescribed thiazide or thiazide-like diuretics, including hydrochlorothiazide (HCTZ) and chlorthalidone (CLD), as first-line therapies. While CLD is considered to be interchangeable with HCTZ, recent studies have indicated that CLD has a longer duration of action and is also 1.5 to 2 times as potent as HCTZ.

Researchers recently performed an analysis of clinical and economic outcomes for these 2 treatment options. They presented results during a poster session at the AMCP meeting in a poster titled Comparisons of Costs and Clinical Outcomes in Hypertensive Patients Treated with Chlorthalidone or Hydrochlorothiazide,

All of the study participants were adult patients (≥18 years of age) with at least 1 diagnosis of hypertension. Patients also received ≥2 prescriptions of CLD or HCTZ and were continuously enrolled for at least 6 months preceding and 2 years following their first prescription of either drug. Within the study sample, CLD and HCTZ cohorts were matched in a 1:5 ratio using a propensity score method.

Outcome measures were rates of major hypertension-related complications and rates of hospitalizations and emergency department (ED) visits, and healthcare costs, including inpatient care, outpatient care, ED visits, and other medical care costs.

Using clinical and economic outcome data from the i3 Innovus database to compare clinical outcomes and urgent care utilization, the CLD cohort (n=634) experienced a significantly lower rate of hypertension-related complications compared with the HCTZ cohort. The 2 samples did not differ significantly in the proportions of hospitalized patients or the number of ED visits during a 2-year postindex period.

Economic outcome analysis showed that the CLD cohort incurred significantly lower total healthcare costs than the HCTZ-treated patients. The researchers concluded that hypertensive patients treated with CLD experienced fewer complications and accrued significantly lower medical and total healthcare costs than patients treated with HCTZ.

Limitations to the study cited by the researchers included the retrospective, observational design of the study that may have resulted in unobserved cofounding factors affecting the results. The CLD cohort was greatly outnumbered by the HCTZ cohort; however, the factors that influenced physicians’ decisions to prescribe CLD rather than HCTZ were not available in the claims data. While the propensity score matching method was able to balance the observed differences between cohorts, it might not be able to adjust for the unobserved factors.

This study was supported by Takeda Pharmaceutical Company.