Opioid Analgesics & Medicaid: Prevalence of Potential Misuse and Inappropriate Prescribing Practices

Background: Dramatic increases in prescription opioid misuse and deaths from opioid overdose are a growing public health concern in the United States, with the costs of opioid misuse, abuse, and associated health consequences estimated at $72.5 billion annually. Medicaid populations have high rates of substance use disorders (SUDs), a risk factor for opioid abuse and overdose. Further, it is estimated that Medicaid enrollees are prescribed opioids at a rate that is twice the rate of non-Medicaid populations, and are at six times the risk of prescription drug overdose. Thus, it is critical to examine potential opioid misuse and inappropriate prescribing among Medicaid enrollees.

Objective: To describe the use of opioids and determine the prevalence of potential opioid misuse and inappropriate prescribing of opioids among the Georgia (GA) Medicaid population.

Data: The study utilizes individual pharmacy claims data from the GA Medicaid pharmacy claims database from 2009-2014. We restricted our study sample to individuals who received an opioid prescription (short or long acting extended release opioids) during the study period and are between the ages of 18-64. Individuals with diagnoses of cancer were excluded from the study.

Measures and Methods: The dependent variables of interests in the study are five indicators listed in the literature that assess potential misuse by patients or inappropriate prescribing practices by providers. These indicators include having overlapping opioid prescriptions, overlapping opioid and benzodiazepine prescriptions, overlapping opioid and suboxone prescriptions, long-acting/extended release (LA/ER) opioids prescribed for acute pain, and high daily doses of opioids (>100 morphine milligram equivalents). Descriptive analysis using both graphical and summary statistics analyses (comparisons of means, medians, standard deviations etc.) will be conducted by various patient characteristics (e.g., age, gender, race, insurance type (FFS/Managed Medicaid), physician characteristics (e.g., gender, race, specialty), and physician-patient relationship (diagnosis such as acute or chronic pain) over time.

Results: Preliminary analyses were conducted using 2012 data, which includes 758,595 observations representing 150,731 individuals. Preliminary results indicate 7% of the sample receiving opioid/opioid overlapping prescriptions, 18% of the sample receiving opioid/benzodiazepine overlapping prescriptions, and 0.11% of the sample receiving opioid/suboxone overlapping prescriptions. Results also indicate 11% of the men and 6% of the women in the sample receiving opioid/opioid overlapping prescriptions and 20% of the men and 17% of the women receiving opioid/benzodiazepine overlapping prescriptions. Analyses of the high daily dosage and LA/ER prescriptions written for acute pain are currently been carried out, and will be presented at the conference along with the results of the full sample.

Conclusions: Preliminary results show 18-24% of the sample receiving overlapping prescriptions indicating potential misuse and inappropriate prescribing practices within the Medicaid population in GA. Analyses of the full sample will help us to determine if particular characteristics of patients and/or physicians, as well as particular diagnoses of patients within the Medicaid population are more (less) likely to be prone to potential misuse and inappropriate prescribing of opioid analgesics in comparison to other groups. The study will also help us to identify overall trends in the data over time.