Persistent opioid use among patients with urolithiasis: a population based study

Background — Urolithiasis can result in acute, short-lived pain for which opioids are often prescribed. The risk of persistent opioid use following an initial presentation for urolithiasis is unknown.

Objective — To describe rates of opioid prescription and identify risk factors for persistent opioid use among patients with urolithiasis.

Design, Setting, and Participants — This was a population-based study of all patients diagnosed with urolithiasis in Ontario between 2013 and 2017 using administrative databases.

Outcome Measurements and Statistical Analysis — The primary outcome was persistent opioid use, defined as dispensing of opioids between 91 and 180 d after presentation. Multivariable logistic regression and Cox proportional hazard models were used to identify factors associated with outcomes.

Results and Limitations — Of 101 896 previously opioid-naïve patients, 66% were prescribed opioids at diagnosis and 41% of those were dispensed more than 200 oral morphine equivalents (OMEs). For those patients prescribed opioids, 9% had continued use. In adjusted analysis, the number of healthcare visits and having a stone intervention were associated with a higher risk of persistent opioid use (p < 0.0001). Total OME dispensed at presentation was highly associated with persistent use: for >300 OME the odds ratio (OR) was 1.59 (95% confidence interval [CI] 1.41–1.79). Among those who had an intervention, the number and type of procedure were also associated with persistent use: the OR for shockwave lithotripsy compared to ureteroscopy was 1.65 (95% CI 1.42–1.92). This study is limited by the accuracy of the diagnostic and procedural administrative codes available.

Conclusions — The majority of urolithiasis patients were prescribed opioids and 9% of previously opioid-naïve patients exhibited persistent opioid use 91–180 d after their initial urolithiasis visit.

Patient Summary — In this study we found that 9% of patients prescribed opioids at presentation for kidney stones filled an additional prescription 3–6 mo later. Risk factors for this continued use included a higher dose of opioids prescribed in the initial period and the type of kidney stone surgery.