Cost effectiveness of 24-hour ambulatory blood pressure monitoring in evaluation and treatment of essential hypertension.

We wanted to determine if use of ambulatory blood pressure monitoring (ABPM) was cost effective, preventing unnecessary drug therapy in patients misdiagnosed as having essential hypertension, with elevated office blood pressures and normal ambulatory blood pressure. To address this issue we surveyed costs to the patient for antihypertensive drug therapy in 1990 of five local pharmacies in southeastern Michigan. Patients studied (n = 192) were seen in a private, general internal medicine practice in rural southeastern Michigan and received ABPM to assess the presence of hypertension and the adequacy of blood pressure treatment. We ascertained the average, minimal, and maximal drug cost to the patient per unit dose at the local pharmacies. The average yearly cost for patients on antihypertensive medications at pharmacies in southwestern Michigan was $578.40, with figures varying from $94.90 to $4361.75. Although there is no standard reimbursement amount for ABPM, at $188 per monitoring, the cost of monitoring this entire group of patients would offset exactly the cost of medication for the group of patients found to have only office hypertension. As such, third-party insurance carriers should consider reimbursement for ABPM in hypertension to decrease pharmaceutical cost and its attendant potential side effects. In conclusion, our study results suggest that ABPM is cost effective in an outpatient setting in preventing unwarranted drug therapy and the inappropriate diagnosis of hypertension.