Effect of narcotic prescription limiting legislation on opioid utilization following lumbar spine surgery.

Background Context: Prescription opioid abuse is a public health emergency. Opioid prescriptions for spine patients account for a large proportion of use. Some states have implemented statutory limits on prescribers, however it remains unclear whether such laws are effective.

Purpose: This investigation compares opioid prescription patterns for patients undergoing lumbar spine surgery before and after the passage of statewide narcotic-limiting legislation in Rhode Island.

Study Design/setting: Retrospective review of prospectively-collected medical and pharmacologic data.

Patient Sample: Two patient cohorts (pre-law January 1, 2016-June 31, 2016 and post-law June 1, 2017-December 31, 2017) that included all patients undergoing selected lumbar spine surgeries (lumbar discectomy, lumbar decompression without fusion, and posterior lumbar fusion).

Methods: Demographic and surgical variables were collected from the patient's medical charts, and information on controlled substances was collected from the state prescription drug monitoring program database. Variables collected included the number of pills and total morphine milligram equivalents (MMEs) of the first prescription, number of prescriptions filled within 30 days of surgery, total MMEs filled in the 30-day postoperative period, and total MMEs filled from 30 to 90 days after surgery. For comparison of continuous variables, t test or Mann-Whitney U test were used as appropriate. Chi-squared analysis was utilized for comparison of categorical variables. Independent risk factors for prolonged postoperative opioid use were evaluated using logistic regression.

Results: There were no significant differences between pre-law (n = 241) and post-law (n = 311) cohorts in terms of age, sex, preoperative opioid use, or preoperative anxiolytic use (p > .05). A greater than 50% decline was observed among all patients from the pre-law to the post-law period in terms of the number of pills (51.61 vs 23.60 pills, p < .001) and MMEs (525.56 vs 218.77 MMEs, p < .001) provided in the first postoperative opioid prescription. The mean total MMEs provided in the first 30 days decreased significantly (891.26 vs 628.63 MMEs, p < .001) despite an increase in the average number of opioid prescriptions filled (1.75 vs 2.04 prescriptions, p = .002) during this time. There was no significant difference in mean MMEs filled from 30 to 90 days. Upon subgroup analysis, there was a statistically significant decline in both the mean first prescription and total 30-day MMEs regardless of preoperative opioid status (all p < .05) or specific procedure performed (all p < .05). Preoperative opioid use was strongly associated with prolonged postoperative opioid requirements throughout the study period (OR 4.71, 95% CI 3.11-7.13, p < .001). There were no significant differences between cohorts in terms of emergency department (ED) visits or unplanned hospital readmissions at 30 and 90 days following surgery (all p > .05).

Conclusions: The institution of mandatory statewide opioid prescription limits has resulted in a significant reduction in initial and 30-day opioid prescriptions following lumbar spine surgery. Decreased opioid utilization was observed in all patients, regardless of preoperative opioid tolerance or procedure performed. No significant change in postoperative ED visits or unplanned hospital readmissions was seen following implementation of the legislation. This investigation provides preliminary evidence that narcotic limiting legislation may be effective in decreasing opioid prescriptions after lumbar spine surgery for both opioid-naïve and opioid-tolerant patients.