Does exposure to conflict of interest policies in psychiatry residency affect antidepressant prescribing?

Abstract

Background: Academic medical institutions have instituted conflict of interest (COI) policies in response to concerns about pharmaceutical industry influence.

Objective: To determine whether exposure to COI policies during psychiatry residency training affects psychiatrists' antidepressant prescribing patterns after graduation.

Research design: We used 2009 physician-level national administrative prescribing data from IMS Health for 1652 psychiatrists from 162 residency programs. We used difference-in-differences estimation to compare antidepressant prescribing based on graduation before (2001) or after (2008) COI policy adoption across residency program groups with maximally, moderately, and minimally restrictive COI policies. The primary outcomes were shares of psychiatrists' prescribing of heavily promoted, brand reformulated, and brand antidepressants.

Results: Rates of prescribing heavily promoted, brand reformulated, and brand antidepressants in 2009 were lower among post-COI graduates than pre-COI graduates at all levels of COI restrictiveness. However, differences between pre-COI and post-COI graduates' prescribing of heavily promoted medications were larger for maximally restrictive programs than both minimally restrictive programs [-4.3 percentage points; 95% confidence interval (CI), -7.0, -1.6] and moderately restrictive programs (-3.6 percentage points; 95% CI, -6.2, -1.1). The difference in prescribing reformulations was larger for maximally restrictive programs than minimally restrictive programs (-3.0 percentage points; 95% CI, -5.3, -0.7). Results were consistent for prescribing of brand drugs.

Conclusions: This study provides the first empirical evidence of the effects of COI policies. Our results suggest that COI policies can help inoculate physicians against persuasive aspects of pharmaceutical promotion. Further research should assess whether these policies affect other drug classes and physician specialties similarly.