Is Prescription Drug Abuse Underreported? 

UHCOP Study Finds High Rate of Multiple Providers Used for Controlled Substance Prescriptions in Texas

A recent study led by UH College of Pharmacy researchers on the number of healthcare providers from which individual patients are receiving prescriptions for controlled substances suggests that the prescription drug problem in Texas may be underreported.

Published in the October 2016 issue of the journal Pain Medicine, the study utilized data from the Texas Prescription Drug Monitoring Program (PDMP) – the online database in which all controlled substance prescriptions dispensed in the state are logged – to identify multiple provider episodes (MPEs) for the drugs. MPEs have been used to identify prescription drug misuse/abuse, serving as an indicator for doctor shopping.

During the time of the study, the Texas PDMP was operated by the Texas Department of Public Safety (DPS) but has since been moved under the jurisdiction of the Texas State Board of Pharmacy. This monitoring program collects and monitors data for all controlled substances dispensed by a pharmacy in Texas. It also provides the ability for prescribers to review their own prescribing histories.

Defined as individuals who are using five or more prescribers and five or more pharmacies within a 12-month period, MPEs – especially those tied to controlled substance prescriptions (or CSPs) – are among the factors associated with abuse and overprescribing. Some studies have examined MPEs of five prescribers and five pharmacies in a three-month period, so by some accounts, the UH study is a conservative estimate.

40M Controlled Substance Prescriptions

Study parameters included individuals in this database who filled at least one controlled substance prescription. Covering the period from June 2013 to June 2014, the PDMP data consisted of nearly 40 million controlled substance prescriptions written by a little more than 113,000 prescribers and dispensed from more than 5,000 pharmacies.

According to their analysis of the data, 71.30 patients per 100,000 people in Texas were involved in MPEs. In comparison, a similar study conducted in Washington found that 7.3 patients per 100,000 people were involved in MPEs.

Lead authors of the study – recent UHCOP Pharmaceutical Health Outcomes and Policy doctoral program graduate Erin Ferries, Ph.D., MPH, and her faculty advisor, UHCOP Assistant Professor Marc Fleming, Ph.D., MPH, R.Ph. – said this is the first study of its kind utilizing data from the Texas PDMP to research controlled substance prescriptions and multiple provider episodes.

"Not a lot of states have conducted analysis like this, so we don’t have a lot of comparison," Ferries said. "However, when you do compare it to a state like Washington, multiple provider episodes are occurring more frequently in Texas."

Opioids Account for 40 Percent of CSPs

Fleming said he is concerned about the fact that opioids accounting for nearly 39 percent of all controlled substance prescriptions dispensed to Texas residents in 2013.

"If providers are not actively checking for the people that don’t have a valid medical need, then it sort of prevents (the system) from working properly," Fleming said.

The absence of clinical and diagnostic information in the PDMP prevented the authors from assessing the appropriateness of CSP use, or even whether individual patients actually took the medications or whether they were diverted to the black market after being filled. In addition, only Texas residents were included in the data set and those residents out-of-state who filled prescriptions in Texas were excluded.

“The multiple provider episode figure might be understated because it’s not counting other patients that are coming to the state and getting prescriptions from multiple doctors and pharmacies as well,” Ferries said.

Also contributing to the study were fellow UHCOP faculty researchers Rajender R. Aparasu, Ph.D., FAPhA, Hua Chen, M.D., Ph.D., and Michael L. Johnson, Ph.D.; and University of Wisconsin School of Medicine and Public Health’s Aaron M. Gilson, Ph.D., M.S., MSSW.

-- by Ameena Rasheed