Quebec researchers identify biomarkers linked to chronic pain

CTV News

09-07-2025

Smoking has been recognized as a risk factor for a very long time. People who smoke experience more pain, but those who smoke the most experience even more pain. Pictured here is a public ashtray in Ottawa in 2016. THE CANADIAN PRESS/Sean Kilpatrick
Two biomarkers identified by a research team at Laval University could lead to improved management of chronic musculoskeletal pain (CMP).
Professor Clermont Dionne's team found that the presence of acrylamide and cadmium in the body increased the risk of CMP by 24 per cent and 56 per cent, respectively.
'We don't really understand what causes most of these syndromes,' said Dionne, who is a professor in the Department of Social and Preventive Medicine and a researcher at the Quebec University Hospital Centre (CHU de Québec) – Laval University Research Centre and VITAM – Sustainable Health Research Centre.
'It causes a lot of disability,' Dionne explained. 'Even if patients eventually recover within a few weeks, these are recurrent syndromes, so the pain will come back.'
Acrylamide and cadmium are toxic compounds found in cigarette smoke, but also in food and other products that people can be exposed to daily.
Researchers believe that their accumulation in the body could influence the nervous system and contribute to chronic pain, at least in some people.
For reasons that are still poorly understood, CMP is very frequently associated with smoking.
By analyzing data from a large U.S. health and nutrition survey, Dionne and his colleagues found an increased risk of chronic pain associated with tobacco use.
The presence of acrylamide in the body increased the risk of chronic pain by 26 per cent, compared to 56 per cent for the presence of cadmium.
The combined effect of the two substances doubled the risk compared to non-smokers.
'These results suggest that the link between smoking and CMP is mediated by acrylamide and cadmium and that these substances, also present in food and the environment, could serve as biomarkers for CMP,' the study authors said.
A previous study had measured a statistical association between blood concentrations of acrylamide and cadmium and chronic pain in the neck, shoulders, and lower back in a representative sample of the general population.
'Smoking has been a known risk factor for a very long time,' said Dionne. 'People who smoke have more pain, but those who smoke the most also have the most pain, so it's a sign of causality.'
The data from the new study, said Dionne, could initially lead to a less subjective assessment of these pains.
It could also make it possible to evaluate the effectiveness of the interventions offered to patients and lead to measures to reduce exposure to these substances or develop treatments to reduce their concentrations in the body.
Currently, Dionne said, chronic pain management is 'at a dead end,' and patients are too often simply told to learn to 'manage their pain'—a situation made more complex by the fact that, in most cases, the cause of the problems remains a mystery.
'(The study) could lead to better personalization of these syndromes,' he said. 'If it allowed us to identify some of the people who suffer from these problems and treat them differently because they have a different source of problems, then we could advance knowledge and prevention.'
We often look for a biomechanical explanation for the problem, added Dionne, 'but we could imagine that there are potentially other mechanisms at play in some people.'
'This changes the biomechanical paradigm somewhat,' he said. 'It could change the way we approach research and, eventually, the treatment of chronic musculoskeletal pain issues.'
It is estimated that CMD affects five per cent of the Canadian population.
The findings of this study were published in the medical journal Pain.
- This report by The Canadian Press was first published in French on July 9, 2025.