News COPD and asthma in patients with opioid dependency: a cross-sectional study in primary care The following was taken from the latest Clinical Update. To view the full clinical update by Euan Lawson, please register to become a Premium Member. COPD and asthma in patients with opioid dependency: a cross-sectional study in primary care. Mehta S, Parmar N, Kelleher M et al. NPJ primary care respiratory medicine. 2020;30:4. Available open access here. This study focused on people who were prescribed methadone in Lambeth in London. They only took the records of those who were in primary care so no specialist service prescribing was included. Out of the denominator of 321,795 patients they found 676 (0.21%) people who had been prescribed methadone from the 46 practices. As well as all the usual demographic and disease data they also dug into smoking status. They compared the prevalence of lung disease in these 676 people on methadone to the rest of the population. The COPD prevalence was 12.4% vs 1.1% and the asthma prevalence was 14.2% vs 4.4%. People with both COPD and asthma had a prevalence of 5.0% vs 0.3% in the general population. Overall, 97.3% were smokers and out of these they found that 81.2% were current smokers and 16.1% were ex-smokers. Methadone was an independent determinant of asthma, even when adjusted for smoking status with an odds ratio of 3.21 (95% CI 2.52-4.10). Prevalence of respiratory conditions among people who use illicit opioids: a systematic review. Hulin J, Brodie A, Stevens J, Mitchell C. Addiction. 2019. Available here. This systematic review found 44 papers exploring respiratory health and illicit opioids. The meta-analysis yielded an estimated prevalence of asthma of 8.5% in people who inject opioids and 20.2% in people who smoke opioids. The COPD prevalence in people who inject was 2.7% and 17.9% in people who smoke. Commentary: So, you can’t spend long looking after people who use drugs without noticing that they don’t have good lung health. In fact, it’s often terrible. But how terrible and how common is it? The Lambeth study tells us a little more from the primary care perspective, important given that’s where most people should be getting their treatment. There are some marked limitations with their approach. As the authors point out only 21% of people are treated in primary care though the authors do suggest the Lambeth area was atypical at the time of the study and it may have been as high as 51%. One suspects that they are likely to be at the less complicated end of the spectrum and it’s probable that these patients represent a relatively healthy cohort of people on methadone. Complex need clients are more likely to be managed in specialist services. The Hulin paper gets down to the nitty gritty and on the face of it this seems like a lot of papers. However, they were wildly different, or in the jargon, heterogeneous. This is particularly evident when you look at the 95% predictive intervals which make me wonder how much stock we can put in the averages. The 95% predictive interval for that 17.9% prevalence of COPD stretches from 0.6% to 89.5%. That’s not massively helpful so interpret with caution. There’s not much doubt that the evidence shows that asthma and COPD are much more common in opioids users. We still don’t have evidence that is good enough to come up with a credible estimate. Additionally, these are, of course, only the people who have been diagnosed. It’s very likely to be an under-representation of the scale of the problem. In conclusion: all of this is bad, but these studies suggest it is worse, much worse, and perhaps the most important message is that we have a catastrophic gap in care. At one point the authors intone in dry academic style expected of journals: “Current configuration of addiction services in the UK has resulted in the separation of addiction management from the management of long-term conditions.” Oh yes. It is resulting in a devastating shortfall in care and lung health is one of the more obvious manifestations of that. Papers included in the full clinical update: Injecting-related health harms and overuse of acidifiers among people who inject heroin and crack cocaine in London: a mixed-methods study. Prescription of benzodiazepines, z-drugs, and gabapentinoids and mortality risk in people receiving opioid agonist treatment: Observational study based on the UK Clinical Practice Research Datalink and Office for National Statistics death records. Do interruptions to the continuity of methadone maintenance treatment in specialist addiction settings increase the risk of drug‐related poisoning deaths? A retrospective‐cohort study. Comparative effectiveness of different treatment pathways for opioid use disorder. Self-care habits among people who inject drugs with skin and soft tissue infections: a qualitative analysis. “Alcochoix+”: controlled drinking within a structured programme - a cohort study in Switzerland.