Smoking linked to back pain

Smokers, especially younger smokers, are more likely to report low back pain than people who have never smoked.

To know if smoking increases the risk of low back pain, a problem that affects an estimated 8 in 10 adults during some point in their lives, researchers identified and reviewed 81 studies from around the world involving smokers, former smokers, or never-smokers and low back pain conducted between 1966 and 2009. Of these, 40 studies involving more than 300,000 adults and adolescents met the standards for the analysis. The researchers subjected the data of the individual studies to further statistical analysis to tease out the strength of relationships even as the studies reported various outcomes. They determined that even though the data did not prove smoking leads to low back pain, the analysis of previous  literature suggested a "fairly modest" association between smoking and low back pain.

It was found that current smokers (adolescents or adults) are at  31% higher risk of low back pain compared with never smokers but this estimate is only for low back pain for one day or more during the past 12 months. The smoking/low back pain association was strongest for chronic or disabling low back pain but the researchers cautioned that none of the studies were designed to determine if there was a cause and effect relationship.

It is not known why smoking may be associated with lower back pain, although there are a number of possible explanations, including reduced blood supply to the spine, increased risk of osteoporosis, and the increased circulation of pain conducting chemicals in the blood from smoking.

The researchers concluded smoking is modestly associated with the risk of low back pain and the effects may be at least partly reversible.