Bruk av andre vanedannende legemidler blant opioidbrukere med langvarige smerter

Abstract

Bakgrunn: Opioider for behandling av langvarige smerter kan forskrives på blå resept, men bør ikke brukes samtidig med andre vanedannende legemidler. Hensikt: Å undersøke bruk av opioider på blå resept i perioden 2009-2019, samt å studere bruk av andre vanedannende legemidler (benzodiazepiner og z-hypnotika) blant dem som fikk opioider på blå resept i 2019. Metode: Data ble hentet fra Reseptregisteret. En prevalent opioidbruker i 2019 ble definert som en person med minst én utlevering av et smertestillende opioid på blå resept for langvarige smerter også i 2018. Bruk av andre vanedannende legemidler ble definert som minst én utlevering av et annet vanedannende legemiddel i løpet av samme år. Resultater: Totalt 18 443 personer (67% kvinner) fikk utlevert opioider på blå resept i 2019, en økning fra 5 568 i 2009 via 10 693 i 2016 og 16 133 i 2017. Av de 18 443 var 14 202 (77%) prevalente opioidbrukere. Blant de prevalente brukerne fikk 88% utlevert 100 mg orale morfinekvivalenter (OMEQ) eller mindre per dag. Totalt fikk 54% av de prevalente opioidbrukerne utlevert minst ett annet vanedannende legemiddel i 2019. Z-hypnotika var oftest forekommende blant de som brukte 100 mg OMEQ eller mindre per dag, mens benzodiazepiner alene eller i kombinasjon med z-hypnotika dominerte blant opioidbrukerne som fikk utlevert mer enn 100 mg OMEQ per dag. Mengden utlevert av andre vanedannende legemidler økte med mengden opioider brukt per dag. En større andel kvinner enn menn fikk utlevert andre vanedannende legemidler i 2019. Konklusjon: Studien indikerer at bruk av andre vanedannende legemidler forekommer hos en stor andel av dem som får forskrevet opioider på blå resept. Dette er tegn på et uheldig forskrivningsmønster som bør studeres nærmere.

Background: Approximately 30% of the adult Norwegian population reports experiencing chronic pain, i.e. pain persisting more than three months. Opioids are indicated to treat moderate-to-severe pain. Since 2008, opioids can be reimbursed when prescribed for the treatment of chronic pain in Norway. Opioids have addictive potential and should, according to international and Norwegian recommendations, not be used concomitantly with other addictive drugs such as benzodiazepines (anxiolytics and sedatives) or benzodiazepine-related drugs (z-hypnotics). Aim of study: The aim of the study was to investigate opioid use within the reimbursement scheme in the period 2009-2019 and to calculate the prevalence of use of benzodiazepines and z-hypnotics among prevalent users receiving opioids on reimbursable prescriptions in 2019. Methods: The data were retrieved from the Norwegian Prescription Database. The study population consisted of individuals aged 18 years or older with at least one dispensation of an opioid reimbursed for chronic pain in the period 2009-2019. A prevalent user receiving opioids on reimbursable prescriptions in 2019 was defined as an individual filling at least one reimbursed opioid prescription in both 2018 and 2019. Use of other addictive drugs was defined as being dispensed at least one benzodiazepine and/or z-hypnotic in 2019 among prevalent opioid users. Results: Our results show an increase in the number of individuals receiving opioids on reimbursable prescriptions for the treatment of chronic pain in the period from 2009 to 2019. In 2019, there were 18,443 users of opioids on reimbursable prescriptions (67% women). Of these, 14,202 (77%) were prevalent opioid users.Among the prevalent opioid users, 90% of the women and 84% of the men received opioids corresponding to use of up to 100 mg oral morphine equivalents (OMEQ) per day, while a small proportion (1.5% of the women, 2.9% of the men) received more than the recommended maximum dosage of 300 mg OMEQ per day. In total, 54% of the opioid users were dispensed at least one other addictive drug in 2019. Z-hypnotics were most frequently dispensed to opioid users using 100 mg OMEQ or less per day, whereas benzodiazepines alone or in combination with z-hypnotics were more frequently dispensed to opioid users using more than 100 mg OMEQ per day. The total amount of dispensed benzodiazepines and/or z-hypnotics increased with an increasing number of OMEQs used per day. Women received other addictive drugs more frequently than men. In total, 24% of all the opioid users were first prescribed an opioid under the reimbursement scheme. Interpretation of results: Our study shows that more than half of the individuals receiving opioids on reimbursable prescriptions for the treatment of chronic pain also received other addictive drugs the same year albeit recommendations discourage the use of more than one addictive drug at a time. Also, one-fourth of the individuals received opioids as the first drug under the reimbursement scheme although non-opioid analgesics should preferably be prescribed first. There is a need for observational studies using linked data from national health- and population registers to gain more knowledge about the risk factors for and consequences of use of other addictive drugs among opioid users.