The researchers also replicated the findings in mice, compressing the animals’ sciatic nerves to cause back and leg pain or injecting irritants into the sciatic nerves. When they blocked the animals’ immune response with dexamethasone, a steroid commonly used to treat back pain, the pain became chronic.
Six tips for treating chronic pain
The group then asked whether the chronic pain was due to pain suppression or inflammation suppression. So they gave some mice a prescription anti-inflammatory, diclofenac. The other mice were given one of three other analgesic or pain-relieving medications — gabapentin, morphine and lidocaine.
Only with diclofenac did the pain persist and become chronic.
These findings prompted them to wonder: Are patients who take non-steroidal anti-inflammatory drugs such as ibuprofen or steroids such as dexamethasone to relieve back pain more likely to develop chronic pain?
The researchers turned to data from the UK Biobank, a repository with information about half a million patients’ medical conditions and drug use. They studied 2,163 people with acute back pain, 461 of whom had chronic pain. Researchers have found that those who take NSAIDs have nearly twice the chance of developing chronic back pain as those who take other medications or not.
Dr. Dyachenko said she does not believe her findings affect the issue of opioid addiction. In fact, she said, “to avoid opioids, doctors started prescribing more non-steroidal anti-inflammatory drugs.”
“We need to think more about how to treat our patients,” she said.
The tendency to use NSAIDs persists despite their modest performance. An analysis of randomized clinical trials found that these drugs had virtually no benefit over placebos in reducing low back pain.
Short-term use of NSAIDs may not be harmful, Dr. Atlas says, but the new study, he adds, although not proven that long-term use is harmful, “at least gives a biological mechanism that says short-term use is not the same as long-term use.”