Prescription opioid duration — not dosage — following surgery may be associated with a greater risk for opioid misuse in patients with no prior history of opioid use, according to a retrospective study published in the BMJ.
Investigators evaluated patient data taken from surgical claims in a linked medical and pharmacy administrative database. A total of 37,651,619 commercially insured and opioid-naive patients were included in this retrospective analysis.
Patients were considered naive to opioid treatment if they had ≤7 days of opioid use in the 60 days preceding surgery. The researchers evaluated the association between potential opioid misuse and the duration of opioid prescription/use in the early post-surgical period.
More than half of the patients in the entire cohort received opioid medications after surgery (n=568,612; 56.0%). Opioid misuse — defined by the presence of ≥1 International Classification of Diseases (ninth revision) diagnosis code of opioid dependence, abuse, or overdose — was identified in 5906 of these patients, starting 4 days after surgery (0.6%; 183 per 100,000 person years).
The strongest predictor of opioid misuse was the total duration of opioid use. In particular, the hazard of opioid misuse was increased by 44% with each additional prescription refill and by 19.9% with each additional week of opioid use (P <.001 for both).
Prescription opioid dosage was found to be a weak predictor of opioid misuse, and reductions in mean dosages over the study period (ranging from 4% to 24%) did not affect duration of opioid use or its association with misuse.
The investigators were unable to account for undocumented pre-surgical opioid use or misuse and acknowledged the possibility of opioid misuse overcoding, which may have led to inflated rates.
Overall, these findings draw attention to the dilemma of clinicians who “are trapped between guidelines that recommend shorter duration and lower dosing of opioid drugs and a subset of patients who request or require opioids beyond the initial prescription.”
Brat GA, Agniel D, Beam A, et al. Postsurgical prescriptions for opioid naive patients and association with overdose and misuse: retrospective cohort study. BMJ. 2018;360:j5790.