The widely-held belief that opioids worsen OSA severity has been debunked in a randomised controlled trial by Australian researchers.
Professional guidelines currently advise that opioids are relatively contraindicated in people with OSA due to their respiratory depression effects, but clinicians from NSW say this recommendation is based on weak and indirect evidence of effects on sleep disordered breathing.
Researchers at the NHMRC Centre for Sleep and Chronobiology and the Woolcock Institute, Sydney say their trial findings, published in Thorax, suggest that opioids only worsen OSA in a small proportion of people with specific clinical phenotypes and genotypes.
In a study of 60 male patients with OSA, they showed that the commonly used dose of morphine (40mg MS Contin) did not worsen severity of the condition overall.
In the randomised crossover trial involving two visits to a sleep clinic, there was no difference in sleep time with oxygen saturation below 90% (T90) or in apnoea-hypopnoea index (AHI) between participants after morphine and placebo.
Despite the overall lack of difference there were large inter-individual responses, with some patients paradoxically showing improvements in OSA with morphine and others showing worsening.