A Time Series Analysis of the Effect of California Regulatory Changes on Multiple Provider Episodes
Prescription monitoring programs (PMPs) are designed to reduce medication diversion by identifying individuals obtaining the same medication from multiple providers (termed multiple provider episodes [MPEs]). This study determined whether recent changes to California’s PMP influenced: 1) the extent that practitioners issue prescriptions for a variety of Schedule II opioids; and 2) the incidence of MPEs involving these opioids. Intervention time series of California’s PMP data was used to determine the effect of requiring practitioners to transition from using triplicate prescription forms for Schedule II medications to security forms for all controlled substances. Outcome measures included changes in number of prescriptions issued for Schedule II long-acting or short-acting (SA) opioids and the MPEs involving these medications. Requiring a security form was associated with a sustained prescribing increase for SA hydromorphone, meperidine, and SA oxycodone; no prescribing changes were found for SA fentanyl, methadone, and SA morphine, or for any long-acting opioids. The same policy change, however, increased MPEs involving all opioids. Further effort is required to determine how California’s PMP can continue to ensure availability of prescription opioids for medical use while better mitigating their diversion.
Currently, there is a dearth of research that has examined the effects of state prescription monitoring programs (PMPs). The relatively few studies detailing the impact of PMPs have consistently demonstrated an immediate and sustained reduction in prescribing or availability of monitored medications, as well as a concomitant increase in the medical use of alternative, and perhaps less effective, medications not subject to the PMP requirements.5,22,24-26,28-31,33 This phenomenon is known as the ‘‘substitution effect.’’30 It was not until 2004 that 2 separate studies described a PMP’s influence not only on prescribing but also on a measure of possible abuse and diversion (ie, ‘‘pharmacy hopping’’).24,26 Both studies determined that New York’s PMP decreased the prescribing of benzodiazepines and contributed to a substitution effect, but also reduced the occurrence of ‘‘pharmacy hopping.’’
Prior PMP research has examined data when these programs were characterized as multiple-copy prescription programs (MCPPs). MCPPs required healthcare practitioners to use government-issued serialized duplicate or triplicate forms to prescribe Schedule II controlled substances, as well as other medications of interest such as benzodiazepines in New York.9 Since the early 1990s, PMPs have increasingly utilized electronic data transmission (EDT) systems. As with MCPPs, EDT systems are intended to reduce the incidence of abuse-related behaviors, including the use of multiple practitioners to obtain different prescriptions for the same medication.10 EDT systems tend to circumvent the restrictions imposed by MCPPs and are believed to better control prescription medication diversion.4,8,19 However, there is yet no empirical evidence to substantiate this judgment.