ABSTRACT
BACKGROUND: Benzodiazepines are recommended for short-term use due to risk of dependence. This study examined characteristics associated with benzodiazepine and opioid dispensing of 7+ days in a Medicaid population with substance use disorder (SUD). METHODS: Using 2014 MarketScan® data, we performed zero-inflated negative binomial regression to ascertain characteristics associated with longer-term use of these medications. RESULTS: Nearly 14% of those with SUDs received 1+ fills of benzodiazepines of 7+ days. The highest rates were among those aged 45-64 (IRR=2.38, p<0.0001) and with non-alcohol SUDs (IRR=1.12, p<0.0001). Individuals with co-occurring psychiatric disorders, particularly anxiety and depression (IRR=1.41, p<0.0001), had high rates of benzodiazepine fills. Receiving a 7+ day oral opioid fill (IRR=1.30, p<0.0001) coincided with increased benzodiazepine dispensing. Similar results occurred for longer-term prescribing of opioids, with higher rates among those with non-alcohol SUDs (IRR=1.23, p< 0.0001). CONCLUSIONS: For many people with SUDs, receiving a benzodiazepine or opioid prescription of 7+ days is not a single occurrence; patients in our sample were more likely to receive 2+ fills than to receive one. Longer-term prescribing is most pronounced among those with co-occurring anxiety disorders. This suggests that anxiety in those with SUD should preferentially not be treated using benzodiazepines. Longer-term polypharmacy with benzodiazepines and opioids coincided. Overdoses among those using both drugs are growing and this study provides evidence that attention to the opioid epidemic should include attention to polypharmacy that includes benzodiazepines.
