Patterns of initial opioid prescribing and its association with short and long-term use among opioid naïve patients: Experience from Malaysia

• Main Authors: Zin, Che Suraya, Nazar, Nor Ilyani, Rahman, N., Ahmad, W., Rani, Nurul Sahida, Kim Swan, Ng
• Format: Conference or Workshop Item
• Language: English
• Published: 2018
• Subjects: RM Therapeutics. Pharmacology; RM300 Drugs and their action
• Online Access: http://irep.iium.edu.my/66542/1/180927_irep_suraya_iasp.pdf; http://irep.iium.edu.my/66542/; https://www.iaspworldcongressonpain.org/program/schedule/#toggle-id-2
• Institution: Universiti Islam Antarabangsa Malaysia

Background and objective In the last decade, the use of opioids for chronic non-cancer pain (CNCP) conditions has increased significantly but it is not clear to what extent the increase reflects short-term use and to what extent it is caused by long-term use. Short-term use of opioids for acute pain conditions is considered appropriate, whereas the long-term use for CNCP (opioid prescribing of 90 days or longer) is always associated with much controversial due to lack of evidence supporting the long-term effectiveness of opioids in CNCP. In opioid naïve patients, the appropriate initial dose and duration of opioid use is suggested without inadvertently promoting the long term use while maintaining the desired effect of pain relief. This study examined the patterns of prescription opioid initiation and its association with short-term or long-term use among opioid-naïve patients. Methods This was a retrospective cohort study evaluating the prescription databases of two tertiary hospital settings in Malaysia. Patients age >18 years old with at least one opioid prescription (buprenorphine, morphine, oxycodone, fentanyl, dihydrocodeine and tramadol) were included. These patients filling their opioid prescriptions between 1st January 2011, and 31st December 2016, with no opioid fills for the previous 365 days. Patients were followed up for another 365 days after the initial opioid prescription. Prescriptions issued by the palliative care department (3%) and prescriptions for morphine written as needed (21%) which were likely used for cancer patients were excluded. Patients were stratified into short-term (< 90 days) and long term-users (≥90 days) based on duration of opioid prescribing during the study period. Proportion of short-term and long-term users, opioid dose per day in mg morphine equivalents and day supply for each patient in each initial prescription were measured. The issuing department whether Emergency Department (ED) or non-Emergency Departments (non-ED) and the opioid formulation either short-acting or long-acting were also measured. Logistic regression was used to measure the association between the characteristics of initial prescription and receiving opioid for short-term or long-term. This analyses controlled for the effects of age and sex. Stata/MP (version 13.1; StataCorp, College Station, TX) was used for all analyses. Results There were 33676 opioid-naïve patients who filled an opioid prescription(n=43432) during the study period. Of these, 29801 (88.5%) were short-term opioid users and 3875 (11.5%) became long-term opioid users. Majority of short-term users (99.09%) and long-term users (96.18%) were receiving a daily dose of <50mg/day in mg morphine equivalents during their initial opioid prescription. Short-term users were most commonly prescribed for 7 to 13 days (50.72%) while long-term users were most frequently prescribed for ≥90 days (50.92%) during the initial opioid prescription. Short-acting opioid formulations were primarily used in both short-term users (99.69%) and long terms users (97.55%). Short-term users were commonly receiving the opioid prescriptions from the ED (60.59%) while long-term opioid users were primarily receiving initial opioid prescriptions from the non-ED (91.69%). Conclusion Majority of opioid naïve patients at tertiary hospital settings in Malaysia were prescribed for short-term use of opioid. Lower doses of opioid and short-acting opioid formulation were primarily used by these opioid naïve patients. The progression to long-term use of opioid among opioid naïve patients were likely attributed to prescribing longer duration of opioid by the non-ED settings.