National Use of Proton Pump Inhibitors From 2007 to 2011

Proton pump inhibitors (PPIs) are a class of therapeutically equivalent medications when used at equivalent doses.^1,2 Despite this, high-cost PPIs continue to be used when low-cost equivalents are available. We sought to estimate the national loss associated with the use of high-cost PPIs over their lower-cost alternatives. Furthermore, we investigated the sociodemographic factors associated with the use of high-cost PPIs.

The 2007-2011 Medical Expenditure Panel Survey (MEPS), a nationally representative survey of the US noninstitutionalized civilian population provided by the Agency for Healthcare Quality and Research (AHRQ), was used for the analysis. The MEPS uses a complex survey design involving 5 interviews over 2 years with 2 overlapping cohorts and includes demographics, expenditures by payer and type, self-reported medical conditions, insurance coverage, and prescription drug information. The survey’s drug data have been found to be valid, especially among chronic medications, and not biased by sociodemographic variables.³

Expenditures, both total and out-of-pocket, and total number of doses were secured across 6 PPIs—esomeprazole, omeprazole, lansoprazole, pantoprazole, rabeprazole, and dexlansoprazole. Omeprazole was classified as low-cost throughout the study period. Pantoprazole was classified as high-cost until it became a generic in 2011. The remaining PPIs were classified as high-cost. Any expenditure for a high-cost PPI resulted in the individual being classified as high-cost. Excess expenditure of high-cost PPIs was determined by individual PPI by year on a per-dose basis.

A logistic regression comparing low- or high-cost PPI users was created across sex, age (per 10 years), region (Northeast, Midwest, West, and South), metropolitan area, modified Elixhauser Comorbidity index,⁴ poverty category (poor, near-poor, low-income, middle-income, and high-income), highest degree (no high school, high school/General Education Development [GED], or more than high school), insurance status (any private, public, or uninsured), and race/ethnicity (white, black, Hispanic, or other). Complex survey weighting was included in all analyses and expenditures were standardized on 2011 dollars. Analysis was conducted using Stata statistical software (version 13; StataCorp) and included the recoding of 1 omeprazole expense outlier down to the 95th percentile and conservatively estimated to 360 doses. The study was judged to be exempt by the Ohio State University institutional review board.

The study included 169 044 individuals, of whom 9463 were classified as PPI users. A total of 5166 individuals were classified as users of high-cost PPIs vs 4297 who were low-cost PPI users. As indicated in Table 1, low-cost PPI expenditures totaled $15.5 billion (95% CI, $13.8-$17.1 billion) compared with $63.4 billion (95% CI, $58.8-$68.1 billion) for high-cost PPIs. Use of high-cost PPIs resulted in $47.1 billion (95% CI, $43.6-$50.7 billion) in excess expenditure, of which esomeprazole accounted for $26.5 billion (95% CI, $23.8-$29.2 billion). In total, $6.69 billion (95% CI, $5.95-$7.43 billion) was excess in out-of-pocket costs paid by the users. The analysis found increased use of high-cost PPIs according to decreasing age, female sex, private insurance, region (Northeast or South), an Elixhauser index of 0, and the highest income category. Table 2 presents both bivariate and multivariate analyses.

Prescription of high-cost PPIs resulted in $47.1 billion of excess expenditure over 5 years. Given the therapeutic equivalence of PPIs, this study not only identifies a significant source of waste, but notes that $6.69 billion of this excess expenditure was paid by patients. While this 1 clinical decision contributes only a small component to the estimated $910 billion of annual waste,⁵ this scenario is similar to those of other profitable drug classes and reflects systematic dysfunction that results in excess cost to patients and society. While systematic reform should be undertaken to increase the development of innovative products, similar efforts should seek to decrease the profitability of drugs that offer no advantage to low-cost generic products.⁶

Corresponding Author: Michael E. Johansen, MD, MS, Department of Family Medicine, Ohio State University, 2231 N High St, Columbus, OH 43201 (michael.johansen@osumc.edu).

Published Online: September 8, 2014. doi:10.1001/jamainternmed.2014.2900.

Author Contributions: Dr Johansen had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design: Johansen, Huerta.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: All authors.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: All authors.

Administrative, technical, or material support: Johansen, Huerta.

Study supervision: Huerta.

Conflict of Interest Disclosures: None reported.

Correction: This article was corrected online September 24, 2014, for an error in the byline.