CCHE Seminar Series: Pharmaceutical Promotion, Physician Response, and Opioid Abuse: Identifying the Role of Physicians in the Opioid Crisis
University of Toronto
Friday October 30, 2020, 10am-12pm, Zoom
Abstract: Physicians play a key role as gatekeepers of prescription opioids, where legal opioids make up an important part of overdoses and deaths. Doctors are entangled in a web of drug-seeking patients, illicit markets for opioids, and the legitimate need for pain relief. In the background are complex interrelationships between socioeconomic conditions, underlying health, and the nature of addiction. Identifying a specific part of the causal chain is unquestionably difficult. This paper investigates the particular role of physicians and the prescriptions they write in the opioid epidemic. There are at least two primary challenges in estimating this relationship. First, physicians write prescriptions in response to patient demand, and so it is inherently difficult to disentangle the supply behaviour of doctors from the demand behavior of patients. The second is measurement: The mechanisms that underlie the path between a prescription and a patient “outcome,” and death in particular, are not obvious and difficult to measure. To address these challenges, I propose an empirical strategy that leverages the relationship between pharmaceutical sales representatives and physicians, combined with the timing of a policy-induced shift of demand. I then exploit variation in these two dimensions to investigate the effect of prescriptions on self-reported measures of opioid abuse, frequency of hospitalization (and intensity of resource use), and death. I first focus on the promotional relationship between pharmaceutical firms and physicians. I link physician-level opioid prescription data to a dataset of all pharmaceutical promotional visits between 2013 and 2016, and estimate the change in opioid prescriptions written following changes in promotion. Because promotions themselves may be driven by demand, I exploit the lag in timing between the announcement and implementation of the expansion in Medicaid coverage following the Affordable Care Act: Pharmaceutical firms ramped up their promotions to doctors in anticipation of new patients before those patients were actually covered and eligible for the prescribed opioids. With these plausibly exogenous changes in prescribing behaviour, I then estimate the change in self-reported measures of opioid abuse and dependence, overdose-related hospitalization frequency and severity, and deaths. In doing so, I am able to capture a more nuanced mechanism of substance abuse as a result of potential mis-prescribing. Given the richness of the data, I am also able to highlight more and less important channels by which opioid prescriptions lead to the worst outcomes. My work sheds light on the role of physicians in the complex phenomenon of the opioid epidemic. It also highlights some of the unintended consequences that arose with Medicaid expansion, and thus some of the socio-economic determinants of the opioid crisis. In light of recent high-profile lawsuits against major manufacturers of opioids for misrepresentation of its addictive qualities, my work provides further insight into the role of the promotional relationship between pharmaceutical firms and harmful patient outcomes.
Boriana is a PhD candidate in economics at the University of Toronto. Her research interests are in Health and Labour Economics, with a focus on understanding the causes and dynamics of changing mortality trends and the opioid epidemic. You may learn more about her research on her website.