PCV93 HEALTH EXPENDITURE COMPARISON OF METOPROLOL SUCCINATE VS METOPROLOL TARTARATE

Abstract

To compare health care expenditures of hypertensive patients on metoprolol tartarate (MT) and metoprolol succinate (MS).Metoprolol, a selective β-1 blocker, is available in two different salt forms in the market- metoprolol succinate (MS) and metoprolol tartarate (MT). Both of these salts are FDA approved for the treatment of hypertension. Several studies have shown similar efficacies between the two salts; however they are priced at different levels because of their pharmacokinetic properties. MT is the short acting salt and is given twice daily, whereas MS is the long acting salt and is given once daily. Two cohorts of patients using MT and MS were selected from 2008 Medical Expenditure Panel Survey (MEPS). Propensity score (PS) matching technique was used to balance the cohorts on various parameters such as demographic information, insurance status and comorbity score. Patients using MT were matched to patients using MS on the logit of propensity score using calipers of width equal to 0.2 of the standard deviation of the logit of the propensity score. To estimate mean expenditure costs and 95% confidence intervals, non parametric bootstrap sampling method was used. A total of 742 patients were found to use metoprolol (MT-388, MS- 354). After PS matching, a total of 594 patients were left in the sample for final analysis (298 patients in each cohort). The average annual expenditure in two groups did not differ significantly. After carrying out non parametric bootstrap sampling using 1,000 samples, MT cohort had $10,779 (95% CI: $10,682- $10,875) average annual expenditure while MS cohort had $9,810 (95% CI: $9,810-$10,003). Both the salts of Metoprolol were found have similar average annual total healthcare expenditure, however once a daily salt (MS) has higher out of pocket cost.