BACKGROUND: In Marin County, an affluent San Francisco Bay Area community, opioid prescribing rates are higher than California averages. Opioid prescribing guidelines caution against the co-prescription of opioids and benzodiazepines because the risk of adverse events, including fatal overdose, increases when these medications are combined. These concerns are more acute in older adults. Risky co-prescribing may be more likely when multiple providers prescribe to the same person. We described opioid and benzodiazepine co-prescribing patterns in Marin County, and the frequency of their combined use among fatal overdoses, in order to inform overdose prevention efforts.
METHODS: To examine prescribing patterns, prescription drug monitoring program data for Marin County from the California Department of Justice were utilized for 2012-2015. An opioid-benzodiazepine co-prescription was defined as the dispensing of both an opioid and benzodiazepine prescription to the same individual within 30 days. We assessed opioid-benzodiazepine co-prescribing overall and by age. We calculated the proportion of individuals whose opioid and benzodiazepine prescriptions were issued by different providers. Toxicology reports from the Marin County Office of the Sheriff Coroner were examined to determine the frequency of opioid and/or benzodiazepine detection among all reported drug overdose deaths (N=39) in 2013.
RESULTS: Among all individuals (N=142,939) who filled an opioid prescription, 24% (n=34,451) filled a benzodiazepine prescription within 30 days. The age group with the highest number of opioid-benzodiazepine co-prescriptions was 55-64 years (n=7,227). The proportion of individuals with an opioid-benzodiazepine co-prescription among those who filled an opioid prescription increased with age, ranging from 7% among individuals younger than 15 years old to 46% among individuals 85 years and older. The majority (60%) of individuals who filled opioid-benzodiazepine co-prescriptions were prescribed these medications by two different providers. Among drug overdose deaths with available toxicology information (92%, n=36), 69% (n=25) had opioids present on the toxicology screen. Nearly half (n=12) of drug overdose deaths for which the toxicology screen identified an opioid also had a benzodiazepine present.
CONCLUSIONS: Opioid and benzodiazepine co-prescribing is common in Marin County, especially for older adults. Given that opioids and benzodiazepines were used concurrently among some fatal overdoses, increased clinician and community education regarding combined medication risks may reduce overdoses. The majority of patients who received both medicines obtained them through different prescribers, suggesting that better coordination and communication among providers may facilitate safer prescribing, and ultimately reduce drug overdoses.