Related Experiment Videos
Beneficial effects from systematic dosage reduction of the diuretic, chlorthalidone: a randomized study within a
Insights
Reducing chlorthalidone dosage from 100 mg to 50 mg effectively controlled blood pressure in hypertensive men. The lower dose was as effective as the higher dose over four months, with improved serum potassium levels.
Area of Science:
- Cardiology
- Pharmacology
- Hypertension Management
Background:
- Chlorthalidone is a diuretic commonly prescribed for hypertension.
- Optimizing antihypertensive drug dosage is crucial for balancing efficacy and minimizing adverse effects.
Purpose of the Study:
- To evaluate the impact of reducing chlorthalidone dosage from 100 mg to 50 mg on blood pressure and biochemical markers.
- To compare the efficacy and safety of reduced-dose chlorthalidone versus standard-dose in hypertensive men.
Main Methods:
- A randomized controlled trial involving 140 hypertensive men from the Multiple Risk Factor Intervention Trial.
- Participants were assigned to continue 100 mg or reduce to 50 mg of chlorthalidone daily for 4 months.
- Blood pressure and biochemical markers (serum potassium, uric acid, glucose, cholesterol, triglycerides) were monitored monthly.
Main Results:
- Initial analysis showed higher diastolic blood pressure in the 100 mg group, but this difference was nonsignificant after adjusting for baseline values.
- Serum potassium levels significantly increased in the 50 mg group, particularly with potassium chloride supplementation.
- Both 50 mg and 100 mg doses of chlorthalidone demonstrated comparable blood pressure control over the 4-month study period.
Conclusions:
- A reduced dose of 50 mg chlorthalidone is as effective as 100 mg for long-term blood pressure management in well-controlled hypertensive men.
- Lowering chlorthalidone dosage may improve serum potassium levels.
- Further research is needed to identify optimal antihypertensive drug doses that maximize efficacy and minimize toxicity.
Abstract:
The purpose of this study was to determine the effects on blood pressure and selected biochemical measures of reducing the dosage of chlorthalidone from 100 mg to 50 mg. Within the larger study (Multiple Risk Factor Intervention Trial), 140 Special Intervention hypertensive men, taking 100 mg of chlorthalidone daily, were randomly assigned to either a continuation of 100 mg or a dosage reduction to 50 mg daily. Men were followed monthly for 4 months. Measures were made of blood pressure, serum potassium, serum uric acid, serum glucose, serum cholesterol, and triglycerides. Blood pressure change from baseline to 4 months revealed a significantly higher diastolic blood pressure in the group continued on the 100 mg dose compared to the dose reduction group. However, analysis of covariance, which took into account baseline differences in blood pressure, resulted in a nonsignificant difference in follow-up blood pressure (systolic and diastolic) between groups. Serum potassium increased significantly in the dose reduction group, especially in those participants taking supplemental potassium chloride. The results of this study demonstrate that a reduced dose of 50 mg chlorthalidone over the 4-month period was as effective as the 100 mg dose in long-term, well-controlled hypertensive men. Careful study of other antihypertensive agents is warranted to determine the drug dose that is maximally effective for blood pressure lowering and that also minimized toxic and adverse effects.