With today marking the start of National Pain Week, a leading neuroscientist explains a fascinating link between the brain and the immune system. It could lead to pain being treated in new and better ways.

It has been widely assumed that talk-based therapies have a significant impact in treating pain because they improve patients’ resilience, or reduce their experience of stress or anxiety. While that may seem logical, there are far more complex physical and chemical processes at play, according to an Australian expert in neuroscience and immunology.

Professor Mark Hutchinson is director of the ARC Centre for Nanoscale BioPhotonics at the University of Adelaide and a keynote speaker at the Australian Palliative Care Conference in September.

He says thousands of trials show that talk-based therapies are the most effective treatment for chronic, persistent pain.

By talk-based therapies, he is referring to therapies such as cognitive behavioural therapy or mindfulness therapy, which have a structured approach and defined outcomes. The therapy generally includes open dialogue about pain and how it fits into other problems the patient is experiencing within their family or community.

“In almost every single case there is something else contributing to that patient’s pain condition, beyond the physical ailment of their own body,” says Professor Hutchinson.

“They have a marriage problem, employment problem or history of abuse, and all of those life experiences contribute to that person’s current state of persistent pain.”

He says that even clinicians tend to think that talk-based therapies reduce persistent pain because they work on a psychological level, improving patients’ coping mechanisms or increasing their ability to accept pain and deal with it.

However, there is now evidence that talk-therapy has a physiological impact on cells within the immune system which contribute to the experience of chronic, persistent pain.

“What has not been widely appreciated until now is the molecular adaptions that occur directly within the pain-processing pathways [in the spine and brain] which enable talk-based therapies to work so well,” he says.

Viewing talk-based therapies as treatments that affect the immune system is significant, as it suggests that the way we think has potential to change how our immune systems respond.

“That is a super scary thing for people to think about, but the studies demonstrate that is actually the case.”

“By viewing talk-based therapies as a treatment that affects the immune system, that really opens up a molecular understanding of how talking about things changes our bodies, and how our brain and spinal cord work.”

Exactly how talking changes the immune system’s cells and molecules remains unclear, but Professor Hutchinson hopes the growing body of knowledge will be harnessed to treat pain in new and better ways.

“The end goal of all of this is to reduce the use of opioids, which don’t necessarily work well across all pain, and to have people attain quality of life without prescription medications which also are often not optimally effective.”

The molecular adaptions which enable talk-based therapies to work are something that could be triggered by the placebo effect (when a patient responds to, say, a sugar tablet, because they believe they are taking a drug).

“We have to stop thinking about placebo as the body lying to us; it is a real molecular event,” says Professor Hutchinson.

“It isn’t a trick, a lie or a falsehood; you can actually train people to respond to a placebo and capture the benefits for a desired outcome. If you can train people to be better placebo responders, then all the better.”

Professor Hutchinson says studies have demonstrated that there is a specific receptor and enzyme system that responds to the conditioning, which could contribute to a significant breakthrough in pain management.

The power of conditioning has been understood since the 1890s; (you’ll have heard of Russian physiologist Ian Pavlov who rang a bell when he fed his dogs, conditioning them so they salivated on hearing the bell). Professor Hutchinson says there is scope to condition patients to the presence of an opioid analgesic, such as morphine, if it is given with a specific sound or taste.

“If you then, after repeated conditioning, just get the sound or taste, our body responds as though we got the morphine, even when it didn’t.”

Professor Hutchinson says that while opioids play an essential role in palliative care – relieving pain and a range of other symptoms – people with a life expectancy of more than two years should not use opioids for pain relief for extended periods of time.

“These are transient acute pain cases, where we only want opioids used very sparingly,” he says.

Professor Hutchinson will deliver a keynote section at the Australian Palliative Care Conference 2017 titled ‘How can talking about pain change the cellular processes of pain?’. This will be followed by a panel discussion on contemporary pain management, facilitated by conference MC Virginia Trioli. Learn more about the conference and register here.

Read more about National Pain Week (24-30 July) here.