Prevalence of long-term opioid therapy in a chronic non-cancer pain population attending a university-based tertiary pain clinic in Sweden. A cross-sectional study

BACKGROUND: Opioid therapy has become a common treatment for chronic pain despite accumulating evidence regarding harm and the lack of data to support efficacy for long-term treatments. The prevalence of opioid treatments in Swedish patients with chronic non-cancer pain is unknown. Hence, the present study aimed to assess a short-term period prevalence of prescribed opioid-use and long-term opioid therapy (LTOT) in a population with complex chronic non-cancer pain.

METHOD: The study population consisted of 1613 patients suffering from chronic non-cancer pain and referred to a university-based tertiary pain clinic in Sweden during 2015-2017. Data from a 360-day period prior to consultation were extracted from the Swedish Quality Registry for Pain Rehabilitation (SQRP) and Swedish Prescribed Drug Register (SPDR). Milligram morphine equivalents per day (MME/day) for dispensed opioids were analysed for a 90-day period preceding consultation and long-term opioid therapy (LTOT) was determined for the entire 360-day period.

RESULTS: The 90-day prevalence was 38% (CI 36-40,8) and the 360-day prevalence was 22.3% (n=360 with CI 20.4-24.4).

CONCLUSION: The prescribing rates of opioids in a Swedish population with complex non-cancer chronic pain were high; two in five patients were dispensed an opioid within a 90-day period prior to consultation.