Evidence form Northwestern University links smoking and chronic pain to a region of the brain associated with addiction and reward. This new evidence was taken from a report that further suggests smoking cessation could become a future strategy for preventing and relieving chronic pain.

“We found that [smoking] affects the way the brain responds to back pain and seems to make individuals less resilient to an episode of pain,” says Bogdan Petre, lead author of the study and a technical scientist at Northwestern University Feinberg School of Medicine.

This is reported in a media release from Northwestern University as the first evidence to link smoking and chronic pain with the part of the brain associated with addiction and reward. The study was published online in Human Brain Mapping.

The results reportedly come from a longitudinal observational study of 160 adults with new cases of back pain. At five different times throughout the course of a year, each of the study subjects was given MRI brain scans, asked to rate the intensity of their back pain, and fill out a questionnaire that asked about smoking status and other health issues. Thirty-five healthy control participants and 32 participants with chronic back pain were similarly monitored.

Scientists analyzed MRI activity between two brain areas (nucleus accumbens and medial prefrontal cortex, NAc-mPFC) that are involved in addictive behavior and motivated learning. The researchers reported that this circuitry is critical in development of chronic pain.

These two regions of the brain “talk” to each other, and scientists discovered the strength of this connection influences who will become a chronic pain patient.

“That circuit was very strong and active in the brain’s of smokers,” Petre said. “But we saw a dramatic drop in this circuit’s activity in smokers who — of their own will — quit smoking during the study, so when they stopped smoking, their vulnerably to chronic pain also decreased.”

Medication, such as anti-inflammatory drugs, did help study participants manage pain, but it didn’t change the activity of the brain circuitry. In the future, behavioral interventions, such as smoking cessation programs, could be used to manipulate brain mechanisms as an effective strategy for chronic pain prevention and relief.

[Source: Northwestern University]