04
July
2018
|
16:01
Australia/Melbourne

Study questions cannabis use for pain

Claims cannabis can be used to treat a wide variety of non-cancer related painful conditions have been dealt a blow by a major new Australian study.

The study of 1500 people, investigated cannabis use in people living with chronic non-cancer pain who had been prescribed opioids.

The Lancet Public Health has published the report which found 'no evidence of a temporal relationship between cannabis use and pain severity or pain interference, and no evidence that cannabis use reduced prescribed opioid use or increased rates of opioid discontinuation.'

The study was led by Dr Gabrielle Campbell from the National Drug and Alcohol Research Centre, at the University of New South Wales in Sydney.

"Chronic non-cancer pain is a complex problem. For most people, there is unlikely to be a single effective treatment.” says Dr Campbell.

“In our study of people living with chronic non-cancer pain who were prescribed pharmaceutical opioids, despite reporting perceived benefits from cannabis use, we found no strong evidence that cannabis use reduced participants’ pain or opioid use over time.”

As cannabis use for medicinal purposes increases globally, the report calls for large, well designed, clinical trials, to be conducted to determine the efficacy of cannabis for chronic non-cancer pain.

That's backed by Bupa GP, Dr Tim Ross.

"We welcome any new initiatives that will help our customers deal with complex and difficult health issues such as chronic non-cancer pain, but we need to ensure these initiatives are studied carefully with good evidence to back their broader release and use," said Dr Ross.

"Otherwise the risk of harm to our customers outweighs the 'rush' to a new and unproven treatment."

"We certainly need more studies looking at cannabis alone for pain relief in chronic non-cancer pain, without the confounder of opioids."

People taking part in the study were asked about "lifetime and past year chronic pain conditions, duration of chronic non-cancer pain, pain self-efficacy, whether pain was neuropathic, lifetime and past 12-month cannabis use, number of days cannabis was used in the past month, and current depression and generalised anxiety disorder."

Participants were surveyed about their reasons for use and perceived effectiveness of cannabis; associations between amount of cannabis use and pain, mental health, and opioid use; the effect of cannabis use on pain severity and interference over time; and potential opioid-sparing effects of cannabis.

"Cannabis use was common in people with chronic non-cancer pain who had been prescribed opioids, but we found no evidence that cannabis use improved patient outcomes," according to the report.

It found people who used cannabis had greater pain and lower self-efficacy in managing pain, and there was no evidence that cannabis use reduced pain severity or interference or exerted an opioid-sparing effect.

Cannabis still has uses

The study did not look at the use of cannabis to treat cancer related pain and makes no claims about its use in that area.

NDARC researchers have found a cannabis compound may help curb frequency of epileptic seizures in rare and serious forms of the condition. It also has proven benefits for chemotherapy-induced nausea and multiple sclerosis.

A naturally occurring compound found in cannabis may help to curb the frequency of epileptic seizures, suggests a review of the available evidence by the NDARC.

"This is an interesting summary and seems to reflect more upon the interaction of cannabis and opioids, rather than the use of cannabis alone to manage pain, which they commented is positive," said Dr Ross.

"As we know, opioids are a poor option for the long term management of chronic non-cancer pain and the interaction with cannabis is another reflection of the harm rather than good they offer."

Since the Australian Federal Parliament passed laws permitting its use in 2016, the number of patients being prescribed medicinal cannabis has been limited but increasing progressively.