Zainab Ahmadi, Eva Bernelid, David C Currow, Magnus Ekström

Low-dose opioids can relieve breathlessness but may be underused in late-stage COPD due to fear of complications, contributing to poor symptom control. We aimed to study the period prevalence and indications of opioids actually prescribed in people with end-stage COPD. The study was a longitudinal, population-based study of patients starting long-term oxygen therapy (LTOT) for COPD between October 1, 2005 and June 30, 2009 in Sweden. A random sample (n=2,000) of their dispensed opioid prescriptions was obtained from the national Prescribed Drugs Register from 91 days before starting LTOT until the first of LTOT withdrawal, death, or study end (December 31, 2009). We analyzed medication type, dispensed quantity, date of dispensing, and indications categorized as pain, breathlessness, other, or unknown. In total, 2,249 COPD patients (59% women) were included. During a median follow-up of 1.1 (interquartile range 0.6-2.0) years, 1,034 patients (46%) were dispensed ≥1 opioid prescription (N=13,722 prescriptions). The most frequently prescribed opioids were tramadol (23%), oxycodone (23%), morphine (16%), and codeine (16%). Average dispensed quantity was 9.3 (interquartile range 3.7-16.7) defined daily doses per prescription. In the random sample, the most commonly stated indication was pain (97%), with only 2% for breathlessness and 1% for other reasons. Despite evidence that supported the use of opioids for the relief of breathlessness predating this study, opioids are rarely prescribed to relieve breathlessness in oxygen-dependent COPD, potentially contributing to less-than-optimal symptom control. This study creates a baseline against which to compare future changes in morphine prescribing in this setting.