A new study published in the journal Human Brain Mapping suggests that people who smoke are more likely to develop chronic back pain. Smokers are advised to quit their habit to reduce the risk of developing the disease. Medical News Today has the full story below.
People who smoke are much more likely to develop chronic back pain than
those who do not smoke. These are the findings of a new study by
researchers from Northwestern University in Evanston, IL.
This is not the first study to link smoking to chronic pain. But
according to the research team, led by Bogdan Petre of the Feinberg
School of Medicine at Northwestern, it is the first study to suggest
that smoking interferes with a brain circuit associated with pain,
making smokers more prone to chronic
back pain.
Back pain is one of the most common medical problems in the US,
estimated to affect 8 out of 10 Americans at some point in their lives.
According to the American Chiropractic Association, back pain is the
main reason for missed days at work and the second most common reason
for doctor's visits.
This latest study, published in the journal
Human Brain Mapping, suggests that smokers could reduce their risk of developing chronic back pain by quitting the habit.
To reach their findings, the researchers analyzed 160 participants who
had recently developed subacute back pain, defined as back pain lasting
4-12 weeks. They also assessed 32 participants with chronic back pain -
defined as having back pain for 5 years or more - and 35 participants
with no back pain.
On five separate occasions over a 1-year period, all participants
completed questionnaires that gathered information about their smoking
status and other health conditions. They also underwent magnetic
resonance imaging (
MRI) brain scans.
The brain scans, the researchers say, were used to assess activity
between two brain regions - the nucleus accumbens and the medial
prefrontal cortex. Both of these regions play a role in addictive
behavior and motivated learning.
Smoking increases brain activity that reduces resilience to chronic back pain
Petre and his team found that the connection between these two brain
regions plays a crucial role in chronic pain development. They explain
that the stronger the connection between them, the less resilient an
individual is to chronic pain.
Smoking appears to affect this connection. The researchers found
that compared with nonsmoking participants, those who smoked had a
stronger connection between the nucleus accumbens and the medial
prefrontal cortex, increasing their risk of chronic back pain. The team
calculated that smokers are three times more likely to develop chronic
back pain than nonsmokers.
"But we saw a dramatic drop in this circuit's activity in smokers who - of their own will -
quit smoking during the study," explains Petre. "So when they stopped smoking, their vulnerability to chronic pain also decreased."
Commenting on their findings, the researchers say:
"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."
The team points out that smoking participants who managed their chronic
back pain with medication - such as anti-inflammatory drugs - did
experience some pain reduction, but that these medications did not alter
brain circuitry.
As such, they suggest that smokers could reduce their risk of chronic
back pain by engaging in smoking cessation programs or other behavioral
interventions that may help them quit the habit.
Because the team's findings show that smoking affects brain circuitry
linked to chronic pain, they suggest that there may be a link between
addiction and chronic pain in general.
Dr. Melanie Novak, M.D., is a pain management specialist who treats all types of chronic pain. Read more about pain management on this blog.