Many people suffer from chronic pain and it’s a challenging condition to treat. A group of drugs known as opioids are widely used, but these can have harmful side effects. In a new Cochrane overview in October 2017, Sebastian Straube from the University of Alberta in Canada and colleagues brought together the findings from 14 Cochrane Reviews to summarise the evidence. He tells us what they found in this podcast.
The co-authors of this review were Charl Els, Tanya D Jackson, Diane Kunyk, Vernon G Lappi, Barend Sonnenberg, Reidar Hagtvedt, Sangita Sharma, and Fariba Kolahdooz.
John: Hello, I'm John Hilton, editor in the Cochrane Editorial and Methods department. Many people suffer from chronic pain and it’s a challenging condition to treat. A group of drugs known as opioids are widely used, but these can have harmful side effects. In a new Cochrane overview in October 2017, Sebastian Straube from the University of Alberta in Canada and colleagues brought together the findings from 14 Cochrane Reviews to summarise the evidence. He tells us what they found in this podcast.
Sebastian: Although there has been an increase in the use of opioids to treat chronic pain which is not due to cancer, the safety and effectiveness of these narcotic pain medications, which are related to opium, has remained controversial.
We conducted a summary of all available Cochrane Reviews to learn more about what these reviews can tell us about the side effects of opioid drugs, when these drugs are used in the medium or long term for chronic pain that is not due to cancer.
We looked at this evidence very carefully, duplicating key steps of the analysis and involving a number of experts in the research team. In that context I would very much like to thank my co-authors – this work truly has been a team effort.
Now, the Cochrane reviews we examined contained a mixture of trials in which opioid medications were compared to placebo or to other treatments, and they examined 14 different opioid medications, including codeine, morphine, and oxycodone. Overall, there were 61 separate studies, with a total of more than 18,000 research participants.
The evidence shows that people who take opioids have a higher risk of experiencing adverse events, such as constipation, dizziness and nausea. About three quarters of the participants who took opioids, in trials comparing opioids with placebos, experienced adverse events and one in thirteen had at least one serious adverse event. However, there is still a need for better quality research to allow people to make decisions about taking, or prescribing, opioids for chronic non-cancer pain. For example, there was no dependable information in the Cochrane Reviews on several of the known and sometimes serious side effects of opioids, including addiction.
In conclusion, given the lack of high-quality evidence to support the use of high doses of opioids for chronic non-cancer pain, and the concerning side effect profile we have demonstrated in our overview, it may be time for health professions, regulators, and policy makers to pay closer attention to prescribing habits for opioids.
John: To read more about these issues, you can find the review at Cochrane Library dot com, with a simple search for 'adverse events and opioids'. That’s also the website to visit for the 14 Cochrane Reviews that Sebastian and his colleagues brought together in their overview.