Abstract
The objective of this study was to compare the cost and effectiveness of initiating therapy with bisoprolol/hydrochlorothiazide (HCTZ), amlodipine, and enalapril in patients with mild-to-moderate hypertension. Both cost and effectiveness were estimated using a decision-tree model, which was based on the design of two clinical trials comparing the three drugs, as well as on clinical practice. The authors obtained the outcome data from the two clinical trials, whereas clinical practice parameters were based on the guidelines of The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (or the JNC-VI), as well as on expert clinical opinion. The results of this model indicate that initiating therapy with bisoprolol/HCTZ results in lower treatment costs as well as shorter time until blood pressure control is achieved. The total cost for patients initially treated with bisoprolol/HCTZ is $401 less and $320 less than the total cost for patients initially treated with amlodipine and enalapril, respectively, over a 3-year period. Most of the difference in total cost between drug treatments is due to the difference in drug cost, although the use of bisoprolol/HCTZ results in lower costs in other categories. Patients initially treated with bisoprolol/HCTZ achieve blood pressure control about 0.5 months faster than patients initially treated with amlodipine and 0.9 months faster than patients initially treated with enalapril. The authors conducted an extensive sensitivity analysis by varying the key model parameters and found that their basic results were robust to changes in the model parameters.