Costs of pregabalin or gabapentin for painful diabetic peripheral neuropathy

Abstract

Objective:

To characterize and compare healthcare resource utilization and costs among patients with painful diabetic peripheral neuropathy (pDPN) newly prescribed pregabalin or gabapentin in a real-world clinical setting.

Study Design:

Retrospective cohort analysis using the MarketScan Commercial Claims and Encounters and Medicare Supplemental Databases (2007–2009).

Methods:

Patients with new prescriptions for pregabalin or gabapentin (index event) in 2008 and ≥1 healthcare encounter with an ICD-9 code for pDPN (250.6 or 357.2) within 30 days prior to the first prescription were identified and propensity score matched; continuous enrollment 12 months pre- and post-index was required. Pre- to post-index changes in 12-month all-cause and pDPN-attributable resource utilization and costs were compared between pregabalin and gabapentin using a difference-in-difference (DID) approach.

Results:

A total of 910 pregabalin patients (48.6% female; mean age 63.3 ± 12.1 years) were matched with 910 gabapentin patients (48.8% female; mean age 63.3 ± 12.1 years). The DID showed no significant differences between cohorts for pre- to post-index changes in any of the all-cause resource utilization categories. While prescription costs increased significantly more with pregabalin (DID −$563; p < 0.0001), the DID of $1603 for total healthcare costs per patient indicated that the pre- to post-index increases of $3081 for pregabalin and $4684 for gabapentin patients were comparable (p = 0.8474). Total pDPN-attributable healthcare costs were significantly higher with pregabalin (DID −$385; p < 0.0001), resulting from higher prescription costs (DID −$432; p < 0.0001). Limitations of this study include the inability to specifically link pDPN with medication prescribing; differences between groups despite propensity score matching; use of proxy measures for adherence parameters; and inability to capture efficacy outcomes.

Conclusions:

Among patients initiating pregabalin or gabapentin, there were no significant differences between the drugs in the pre- to post-index changes in all-cause total healthcare costs, despite the increase in prescription costs for pregabalin.

Keywords::

• Painful diabetic peripheral neuropathy
• Pregabalin
• Gabapentin
• Resource utilization
• Costs

Transparency

Declaration of funding

This study was funded by Pfizer Inc.

Declaration of financial/other relationships

MU, JH, and JM have disclosed that they are employees of Pfizer, Inc. Editorial assistance was provided by E. Jay Bienen, who received funding from Pfizer for his services.

Acknowledgment

This research was presented in part as a poster presentation at International Society for Pharmacoeconomics and Outcomes Research 16th Annual International Meeting, May 21–25, 2011, Baltimore, MD.