How Increasing Medical Access to Opioids Contributes to the Opioid Epidemic: Evidence from Medicare Part D

Abstract

Drug overdoses involving opioid analgesics have increased dramatically since 1999, representing one of the United States' top public health crises. Opioids have legitimate medical functions, but improving access may increase abuse rates even among those not prescribed the drugs given that opioids are frequently diverted to nonmedical use. We have little evidence about the causal relationship between increased medical access to opioids and spillovers resulting in abuse. We use the introduction of the Medicare Prescription Drug Benefit Program (Part D) as a large and differential shock to the geographic supply of opioids. We compare growth in opioid supply and abuse rates in states with large 65+ population shares to states with smaller elderly population shares with a focus on abuse among the Medicare-ineligible population. Part D increased opioid utilization for the 65+ population, and we show that this increase in utilization led to significant growth in the overall supply of opioids in high elderly share states relative to low elderly share states. This relative expansion in opioid supply resulted in an escalation in opioid-related substance abuse treatment admissions and opioid-related mortality among the Medicare-ineligible population, implying meaningful spillovers to individuals who did not experience any change in prescription drug benefits. The evidence suggests that increased opioid supply is associated with economically-important levels of diversion for nonmedical purposes. Our estimates imply that a 10% increase in medical opioid distribution leads to a 7.4% increase in opioid-related deaths and a 14.1% increase in substance abuse treatment admission rates for the Medicare-ineligible population.

Polydrug epidemiology: Benzodiazepine prescribing and the drug overdose epidemic in the United States

“…By 2013, 35.7 million Americans used Medicare Part D, comprising about 70% of all Medicare beneficiaries . Existing literature has demonstrated a link between Medicare Part D prescriptions for opiates on state admissions to substance use treatment facilities and overdose mortality among the population at large and has revealed state variation and trends in opioid prescribing and drug poisonings . This study elaborates on the existing literature in 2 ways.…”

“…Second, this study analyzes the potentially synergistic effects of benzodiazepine and opiate prescriptions. While clinical studies emphasize the multifactorial and frequently polydrug nature of overdose deaths, epidemiological studies have not taken heed of this result, typically examining the effect of prescription opiates in isolation …”

Opioids and the Labor Market

“…In our analysis, we observe the effects of being in a higher opioid prescription rate location rather than whether an individual received a prescription. This could be an advantage given the documented patterns of prescription opioids being consumed by individuals in the local area other than the individual receiving the prescription (Powell et al (2015)). On the other hand, our specification does prevent understanding the direct impacts of prescription along the lines of Laird and Nielsen (2016) or Barnett et al (2017), and there could easily be demographic usage differences within a geographic location.…”

“…The mechanisms creating these labor market effects have also been documented: Increasing the local opioid prescription rate generates diversions to nonmedical uses (Powell et al (2015)), and increasing the local prescription abuse rate increases an individual's likelihood of abusing prescription opioids (Finkelstein et al (2018)). 13 At the individual level, increasing a physician's opioid prescribing rate increases the long-term opioid use of their patients (Barnett et al (2017)).…”

Health insurance and opioid deaths: Evidence from the Affordable Care Act young adult provision

“…First, the DR does not display differential pre‐trends. Second, it is helpful to restrict attention to a single age group in light of evidence that access to opioids among some segments of the population can lead to spillover effects on the entire region through increased drug availability (Powell, Pacula, & Taylor, ).…”