A new study conducted at Northwestern University found further evidence that smokers are at an increased risk for developing chronic back pain.

While medical experts have known for a while that smoking increases a person’s risk of chronic back pain, this study examines why that’s the case. Researchers were keen to learn more about the link between back pain and smoking as back pain affects more than 80 percent of the population at some point in their life. According to the folks at the American Chiropractic Association, back pain is the number one reason for missed work and the second most common reason for doctor’s visits.

Smoking Study

For their study, researchers examined 160 individuals who had developed subacute back pain, which is defined as back pain lasting between  1-3 months. In addition, researchers analyzed 32 participants with chronic back pain – back pain for more than five years – and 35 people with no symptoms of back pain. Patients were asked to complete a health and wellness questionnaire once a year for a period of five years, and they also underwent MRI brain scans to analyze brain activity in the nucleus accumbens and the medial prefrontal cortex. These areas play a role in a person’s addictive behavior and motivated learning.

Without getting too technical, researchers say there is a crucial connection between these two areas of the brain. The stronger the connection between the too, the less resilient a person is to chronic pain. According to researchers, smokers had a stronger connection between these two areas of the brain compared to non-smokers, meaning smokers were more likely to develop chronic pain. In fact, researchers suggest that a smoker is three times more likely to develop chronic back pain than a non-smoker.

But there is good news. Dr. Bogdan Petre said the connection between the nucleus accumbens and the medial prefrontal cortex can be decreased by kicking the habit.

“We saw a dramatic drop in this circuit’s activity in smokers who – of their own will – quit smoking during the study,” said Petre. “So when they stopped smoking, their vulnerability to chronic pain also decreased.”

Petre concluded that his team’s findings are only further evidence that smokers are putting themselves at risk for chronic back pain.

“We conclude that smoking increases risk of transitioning to chronic back pain, an effect mediated by corticostriatal circuitry involved in addictive behavior and motivated learning.”