Influence of pharmaceutical marketing on Medicare prescriptions in the District of Columbia

IMPORTANCE: Gifts from pharmaceutical companies are believed to influence prescribing behavior, but few studies have addressed the association between industry gifts to physicians and drug costs, prescription volume, or preference for generic drugs. Even less research addresses the effect of gifts on the prescribing behavior of nurse practitioners (NPs), physician assistants (PAs), and podiatrists. OBJECTIVE: To analyze the association between gifts provided by pharmaceutical companies to individual prescribers in Washington DC and the number of prescriptions, cost of prescriptions, and proportion of branded prescriptions for each prescriber. DESIGN: Gifts data from the District of Columbia’s (DC) AccessRx program and the federal Center for Medicare and Medicaid Services (CMS) Open Payments program were analyzed with claims data from the CMS 2013 Medicare Provider Utilization and Payment Data. SETTING: Washington DC, 2013 PARTICIPANTS: Physicians, nurse practitioners, physician assistants, podiatrists, and other licensed Medicare Part D prescribers who participated in Medicare Part D (a Federal prescription drug program that covers patients over age 65 or who are disabled). EXPOSURE(S): Gifts to healthcare prescribers (including cash, meals, and ownership interests) from pharmaceutical companies. MAIN OUTCOMES AND MEASURES: Average number of Medicare Part D claims per prescriber, number of claims per patient, cost per claim, and proportion of branded claims. RESULTS: In 2013, 1,122 (39.1%) of 2,873 Medicare Part D prescribers received gifts from pharmaceutical companies totaling $3.9 million in 2013. Compared to non-gift recipients, gift recipients prescribed 2.3 more claims per patient, prescribed medications costing $50 more per claim, and prescribed 7.8% more branded drugs. In six specialties (General Internal Medicine, Family Medicine, Obstetrics/Gynecology, Urology, Ophthalmology, and Dermatology), gifts were associated with a significantly increased average cost of claims. For Internal Medicine, Family Medicine, and Ophthalmology, gifts were associated with more branded claims. Gift acceptance was associated with increased average cost per claim for PAs and NPs. Gift acceptance was also associated with higher proportion of branded claims for PAs but not NPs. Physicians who received small gifts (less than $500 annually) had more expensive claims ($114 vs. $85) and more branded claims (30.3% vs. 25.7%) than physicians who received no gifts. Those receiving large gifts (greater than $500 annually) had the highest average costs per claim ($189) and branded claims (39.9%) than other groups. All differences were statistically significant (p<0.05). CONCLUSIONS AND RELEVANCE: Gifts from pharmaceutical companies are associated with more prescriptions per patient, more costly prescriptions, and a higher proportion of branded prescriptions with variation across specialties. Gifts of any size had an effect and larger gifts elicited a larger impact on prescribing behaviors. Our study confirms and expands on previous work showing that industry gifts are associated with more expensive prescriptions and more branded prescriptions. Industry gifts influence prescribing behavior, may have adverse public health implications, and should be banned.