Analysis of 500,000 people in the UK showed those taking anti-inflammtory drugs to treat pain were more likely to have pain two to 10 years later but this effect was not seen not seen in people taking paracetamol or antidepressants.
The research indicated blocking inflammation with drugs could lead to harder-to-treat pain in the future as inflammation, which is the body’s natural reaction to injury and infection, may prevent acute pain from turning into chronic pain.
Jeffrey Mogil, a professor of pain studies at McGill University in Canada, said: “For many decades it’s been standard medical practice to treat pain with anti-inflammatory drugs. But we found that this short-term fix could lead to longer-term problems.”
To understand the transition from acute to chronic low back pain, researchers followed 98 patients with acute low back pain for three months.
They also examined the mechanisms of pain in both humans and mice.
Researchers found neutrophils – a type of white blood cell that helps the body fight infection – play a key role in resolving pain.
Blocking these cells in mice prolonged the pain up to 10 times the normal duration.
Treating the pain with anti-inflammatory drugs and steroids also produced the same result, although they were effective against pain early on.
Luda Diatchenko, a professor in the faculty of medicine, faculty of dentistry, and Canada Excellence Research chairwoman in human pain genetics, said: “Our data suggest that using drugs like ibuprofen and steroids to relieve pain could increase the chances of developing chronic pain, but proper clinical trials should be done to firmly conclude this.”
The study could have implications for how doctors treat pain in the future.
Massimo Allegri, a physician at the Policlinico of Monza Hospital in Italy and Ensemble Hospitalier de la Cote in Switzerland, said: “Our findings suggest it may be time to reconsider the way we treat acute pain.
“Luckily, pain can be killed in other ways that don’t involve interfering with inflammation.”
However, British academics have stressed the findings are “premature” and more research needs to be done into the hypothesis.
Dr Franziska Denk, senior lecturer at King’s College London, said: “It would most definitely be premature to make any recommendations regarding people’s medication until we have results of a prospectively designed clinical trial.”
Professor Blair Smith, from the University of Dundee, added: “The theory is that inflammation may have a protective effect in the long-term, and that overly reducing inflammation may be harmful.
“However, it is important to note that this is just one study, and more research is needed to confirm and investigate this further.”
The findings of the UK Biobank study were published in Science Translational Medicine.