Effects of hydrocodone rescheduling on opioid use outcomes: A systematic review.

Objective: To evaluate opioid prescribing, dispensing, and use in relation to hydrocodone-containing product (HCP) rescheduling.

Methods: Seven biomedical databases and grey literature sources were searched with keywords and database-specific controlled vocabulary relevant to HCP rescheduling for items published between January 2014 and July 2019. We included English-language quasi-experimental studies that assessed changes in HCP and other opioid prescribing, dispensing, utilization, and opioid-related health outcomes before and after HCP rescheduling. A data extraction sheet was created for this review. Two authors evaluated risk of bias for each included study. Two of 4 authors each independently extracted patient demographics and opioid-related outcomes from the included studies. Conflicts were resolved by a third author.

Results: All studies identified (n = 44) were quasi-experimental in design with 10 using an interrupted time series approach. A total of 24 studies reported a decrease in HCP prescribing by 3.1%-66.0%. Six studies reported a decrease in HCP days' supply or doses by 14.0%-80.8%. There was increased prescribing of oxycodone-containing products by 4.5%-13.9% in 5 studies, tramadol by 2.7%-53.0% in 9 studies, codeine-containing products by 0.8%-1352.9% in 8 studies). Five studies reported a decrease in morphine equivalents by at least 10%, whereas 2 studies reported an increase in morphine equivalents. Differences in populations, sample sizes, and approaches did not allow for a meta-analysis. Details regarding approach and findings were limited in published conference abstracts (n = 16).

Conclusions: Hydrocodone rescheduling was associated with reductions in prescribing and use of HCPs but was also associated with increased prescribing and use of other opioids, both schedule II and nonschedule II.