Prevalence and distribution of long-term opioid therapy in primary care in Uppsala county, Sweden: a retrospective observational study.

Abstract

Introduction: Due to the global increase in opioid prescription rates and the parallel increase in opioid misuse, abuse and opioid-related deaths in many countries, attention on reducing irrational opioid use has become more predominant. Because of the risks related to opioid use and limited evidence for prolonged analgesic effects, the use of long-term opioid therapy (LTOT) in patients with chronic non-cancer pain is questionable. In Sweden, information about the number of patients that are currently on LTOT, how these are distributed among the primary care practices, and what type of opioids that are being prescribed, is lacking. Therefore, this study aimed to investigate the prevalence and distributions of adult patients with LTOT in primary care practices in Uppsala county, Sweden and to investigate the type, quantity and trends of opioid prescriptions in these patients.

Methods: A retrospective study of opioid prescription data was conducted using data from both regional (Region Uppsala) and national (Socialstyrelsen) prescription databases in Sweden. The study population consisted of adult patients in Uppsala county with at least one opioid prescription between 01-06-2021 until 31-05-2022 (Region Uppsala) and 01-01-2016 until 01-09-2022 (Socialstyrelsen). LTOT prevalence rates were calculated by dividing the number of identified LTOT patients with the total number of enlisted patients. ATC-codes of different opioids were used to calculate the total number of prescriptions, users and total prescribed defined daily dose (DDD) per 1000 inhabitants for all opioids. Descriptive statistics were used to examine patient characteristics and opioid use. A Chi-square test was performed to analyze the difference of LTOT prevalence rates between individual primary care practices.

Results: LTOT prevalence rates of 0.77% and 1.13% were reported for the regional and national dataset, respectively. LTOT prevalence rates differed between public primary care practices. Between 2016 and 2021, an increasing trend in the number of prescriptions, users and total prescribed DDD was mainly found for oxycodone and buprenorphine.

Conclusion: LTOT prevalence rates among adult patients in primary care in Uppsala county varied between 0.77% and 1.13% and LTOT patients were not equally distributed among public primary care practices. The use of stronger opioids increased substantially between 2016 and 2021 in Uppsala county, Sweden. Oxycodone and buprenorphine showed the most pronounced increases, whereas only tramadol showed a decreasing trend. Our findings show similarities with results from other European studies, reporting an indication for a shifting trend from the prescription of weaker opioids to stronger opioids. Although our numbers and trends need to be interpreted with caution, the results underline the importance of close monitoring if benefits still outweigh risks and if treatment rationale of opioid use still applies.