The researchers also replicated the findings in mice, either compressing the animals’ sciatic nerves to cause back and leg pain or injecting the sciatic nerves with an irritant. When they blocked the animals’ immune response with dexamethasone, a steroid often used to treat back pain, the pain became chronic.
Six tips for treating chronic pain
Next, the group wondered whether chronic pain resulted from pain suppression or from suppression of inflammation. So they gave some mice a prescription anti-inflammatory called diclofenac. Other mice were given one of three other analgesic or analgesic drugs — gabapentin, morphine and lidocaine.
Only with diclofenac did the pain persist and become chronic.
Those results led them to wonder: were patients taking nonsteroidal anti-inflammatories like ibuprofen or steroids like dexamethasone to relieve their back pain more likely to develop chronic pain?
The researchers used data from the UK Biobank, a repository of information about the medical condition and drug use of half a million patients. They studied 2,163 people with acute back pain, of whom 461 developed chronic pain. Those who took a nonsteroidal anti-inflammatory drug were nearly twice as likely to develop chronic back pain as those who took other drugs or no drugs, the researchers found.
dr. Diatchenko said she doesn’t think her findings address the issue of opioid addiction. In fact, she said, “to avoid opioids, clinicians started prescribing more nonsteroidal anti-inflammatory drugs.”
“We need to think further about how to treat our patients,” she said.
The tendency to use non-steroidal anti-inflammatories persists despite their unimpressive effect. An analysis of randomized clinical trials found that these drugs had almost no benefit over placebos in reducing low back pain.
dr. Atlas says that short-term use of nonsteroidal anti-inflammatories probably isn’t harmful, but the new study, he adds, while not showing that long-term use is harmful, “at least provides a biological mechanism that says use short term not the same as long term.”
