Opioid utility for dyspnea in chronic obstructive pulmonary disease: a complicated and controversial story
Chronic obstructive pulmonary disease (COPD) is common chronic respiratory disorder, predominantly caused by exposure to cigarette smoke or biomass fuels, and it usually affects older adults. Dyspnea in COPD that is unresponsive to traditional management is a challenging disease complication for both the patient and the health care professional. Off-label use of opioids has been advocated as a pharmacotherapy strategy for refractory dyspnea. However, negative respiratory outcomes are a potential concern with opioids drugs, especially among individuals with COPD. In this review, randomized controlled trials evaluating opioid efficacy among individuals with COPD are reviewed and critically analyzed, and data from observational drug safety studies is also presented. In summary, the evidence in support of using opioids for refractory dyspnea in COPD is minimal and weak, and there is mounting data demonstrating that opioids are associated with increased respiratory-related morbidity and mortality in this population. Therefore, current evidence does not support the broad application of opioids for refractory dyspnea among individuals with COPD. However, there may be subsets of individuals that experience modest improvement in dyspnea with opioids, and better understanding predictors and mechanisms of such opioid responsiveness should be a focus of future research endeavours.