Costs of current antihypertensive therapy in Switzerland: an economic evaluation of 3,489 patients in primary care

QUESTION UNDER STUDY: Due to greater life expectancy, costs of medication have increased within the last decade. This investigation assesses health care expenditures needed to manage the current state of blood pressure (BP) control in Switzerland. OBJECTIVES: a) average day therapy costs (DTC) of substances, b) actual DTC of currently prescribed antihypertensive therapy, c) monetary differences of treatment regimens within different BP-groups and different high risk patients, d) estimated compliance-related financial loss/annum and adjusted costs/annum. Single-pill-combinations appear to be useful to increase patient's compliance, to reduce side effects and to bring more patients to their blood pressure goal. METHODS: Costs were identified based on data from the Swiss department of health. We calculated DTC for each patient using prices of the largest available tablet box. RESULTS: The average antihypertensive therapy in Switzerland currently costs CHF 1.198 ± 0.732 per day. On average beta blockers were the cheapest substances, followed by angiotensin converting enzyme inhibitors (ARBs), calcium channel blockers and diuretics. The widest price ranges were observed within the class of ARBs. Most expensive were patients with impaired renal function. Throughout all stages, single-pill-combinations appeared to be significantly cheaper than dual-free-combinations. Stage-II-hypertension yielded the highest costs for dual free combination drug use. The actual costs for all patients observed in this analysis added up to CHF 1,525,962. Based on a compliance model, only treatment amounting to CHF 921,353 is expected to be actually taken. CONCLUSION: A disproportionately high healthcare cost is expected due to compliance reasons. The prescription of mono-therapies appears to be a major cost factor, thus, the use of single-pill-combination therapy can be considered as a suitable approach to saving costs throughout all BP- stages.