According to a US study, people who smoke regularly are at higher risk of developing chronic back pain than non-smokers, The results of the study, which was carried out by researchers from Northwestern University in Chicago (Illinois), were published in «Human Brain Mapping».
The scientists conducted a long-term study with 160 adults that had recently suffered back pain. Over the course of one year, they underwent five MRI brain scans and were asked to rate the severity of their pain, their smoking status and other health problems. Thereafter, 32 participants with chronic back pain and 35 controls were medically monitored. The data showed that smokers have a three-fold higher risk of developing chronic back pain than non-smokers.
In fact, it became clear that smoking impairs the way in which the brain responds to pain. The researchers focused on a circuit between two brain regions, the nucleus accumbens and the medial prefrontal cortex, which are crucial in addictive behaviour and motivated learning.
This circuit appears to play an essential role in the development of chronic pain. It was very strong in smokers, explained study author Bogdan Petre, whereas the activity significantly dropped in those who quit smoking at their own will. «When they stopped smoking, their vulnerability to chronic pain also decreased»
