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Is very low dose hydrochlorothiazide combined with candesartan effective in uncontrolled hypertensive patients?

Kazuo Eguchi1, Satoshi Hoshide, Tomoyuki Kabutoya

  • 1Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University, School of Medicine, 3311-1 Yakushiji, Shimotsuke, Tochigi, Japan. ke112@jichi.ac.jp

Blood Pressure Monitoring
|September 10, 2010
PubMed

Insights

Adding a low dose of hydrochlorothiazide (HCTZ) to an angiotensin receptor blocker (ARB) effectively lowers blood pressure, especially during sleep. This combination therapy improved blood pressure control in hypertensive patients.

Area of Science:

  • Cardiology
  • Pharmacology
  • Nephrology

Background:

  • The efficacy of combining low-dose hydrochlorothiazide (HCTZ) with angiotensin receptor blockers (ARBs) for hypertension management remains debated.
  • Many patients on standard antihypertensive treatments still have uncontrolled blood pressure.

Purpose of the Study:

  • To assess the effectiveness and safety of adding a very low dose of HCTZ to ARB therapy in hypertensive individuals.
  • To evaluate the impact on clinic blood pressure, ambulatory blood pressure, and metabolic parameters.

Main Methods:

  • An observational study involving 41 hypertensive patients inadequately controlled on ARBs alone.
  • Patients received 6.25 mg HCTZ added to their existing ARB regimen (e.g., candesartan).
  • Clinic and 24-hour ambulatory blood pressure (ABP) were measured before and after 2-3 months of combination therapy.

Main Results:

  • Combination therapy significantly reduced both systolic and diastolic blood pressure, with a notable decrease in nighttime (sleep) BP.
  • The proportion of patients classified as 'nondippers' decreased, while 'dippers' and 'extreme-dippers' increased.
  • Serum uric acid levels rose significantly, but other metabolic markers remained unchanged.

Conclusions:

  • Adding a very low dose of HCTZ (6.25 mg) to ARB therapy is a highly effective strategy for lowering both clinic and ambulatory blood pressure.
  • This combination therapy demonstrates particular efficacy in reducing nighttime blood pressure and improving BP dipping patterns.
Abstract

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