Smoking may be an important factor that raises your risk to joint erosion, joint pain, and osteoarthritis.

This was recently examined in a new study that looked at knee cartilage and severity of knee pain in 159 men with knee osteoarthritis.  These men were examined over 30 months (2.5 years), with knee cartilage tested by magnetic resonance imaging (MRI).  The men who were current smokers were found to have an increased risk for cartilage loss in the knee (at the medial tibiofemoral joint and the patellofemoral joint). Current smokers also had higher pain scores at the beginning and at end of the study, than men who were not current smokers. 

The smokers in this study tended to be younger and leaner than the non-smokers with OA.  Normally, it would be expected that younger, leaner people would have lower risk to OA. However, this new study suggests that smoking probably has a separate effect on damage to joint cartilage.  Other studies have shown that changing blood flow through clogging arteries and high blood pressure are linked to cartilage degeneration.  Since smoking may contribute to blood vessel damage, this maybe one way that smoking contributes to cartilage injury, regardless of weight.

It is also important to know that cartilage has no pain sensing nerve fibers.  Since the smokers reported higher pain along with their injured cartilage, it may mean that smoking also damages other components of the joint that do have pain fibers.

[Amin, S, Niu, J, Guermazi, A, Grigoryan, M, et al. Cigarette smoking and the risk for cartilage loss and knee pain in men with knee osteoarthritis. Ann Rheum Dis 2007;66(1):18-22.]

Doctors in Australia took another approach to looking at how smoking affected joints.  They looked at people who had at least one parent having severe osteoarthritis.  They tested a total of 325 people and followed them for 2.3 years.  Smokers had more defects in knee cartilage, with greater cartilage loss in those who smoked longer and who smoked more packs per day.  These effects were strongest in people who had a parent with osteoarthritis.

The authors wrote that, “This study is the first to demonstrate harmful effects of smoking on both cartilage volume loss and cartilage defect development mainly in persons with a family history of severe knee OA.”

[Ding, C, Cicuttini, F, Blizzard, L, Jones, G. Smoking interacts with family history with regard to change in knee cartilage volume and cartilage defect development. Arthritis Rheum 2007;56(5):1521-8.]

Some of the early studies have been unclear about the possible link between osteoarthritis and smoking.  The newer studies suggest there may be a particular genetic susceptibility and that smoking is more damaging to people with a certain gene profile.  The genes that might cause this are not known, but these studies highlight another potential risk factor for developing joint disease and suffering joint pain.

In Summary

• Smoking may lead to defects in knee cartilage
• Smoking may trigger more cartilage loss
• Smokers with OA may suffer more pain than non-smokers with OA
• Smokers may have a greater risk to joint disease if they have a relative with OA
• Those who smoke more packs per day may suffer more severe joint problems
• While OA tends to affect people as they get older, smoking seems to trigger OA in younger people