Treatment of chronic noncancer pain in patients on opioid therapy in primary care: A retrospective cohort study

Abstract

This study sought to characterize the real-world treatment of chronic noncancer pain (CNCP) in patients on opioid therapy in primary care. A retrospective cohort study from 2014-18 was conducted at a multidisciplinary primary care clinic in Chilliwack, British Columbia. Included were adults on daily opioid therapy for CNCP. Patients receiving palliative care or ≤1 visit were excluded. Outcomes of interest included use of opioid/nonopioid pharmacotherapy, number/frequency of visits and proportion of patients able to reduce/discontinue opioid therapy. Seventy patients (mean age 53 years, 53% male, 51% back pain) were included. Median follow-up was 6 visits over 12 months. Sixty-two patients (89%) reduced their opioid dose, 6 patients had no change and 2 patients required a dose increase. Mean opioid dose was reduced from 183 to 70 mg morphine equivalents daily. Twenty-four patients (34%) discontinued opioid therapy, 6 patients (9%) transitioned to opioid agonist therapy and 6 patients (9%) breached their opioid treatment agreement. Nonopioid pharmacotherapy included nonsteroidal anti-inflammatory drugs (64%), gabapentinoids (63%), tricyclic antidepressants (56%) and nabilone (51%). Over half of patients were no longer on opioid therapy by the end of the study. Most patients had a disorder (e.g., back pain) for which opioids are generally not recommended. Overall mean opioid dose was reduced from baseline by approximately 60% over 1 year. Lack of access to specialized pain treatments may have accounted for high nonopioid pharmacotherapy usage. This study demonstrates that treatment of CNCP and opioid tapering can successfully be achieved in a primary care setting. Can Pharm J (Ott) 2020;153:xx-xx.