Solomon and colleagues1 provide observational evidence that the use of opioids in older adults is associated with a number of adverse outcomes, including fracture, cardiovascular events, and all-cause mortality. While the increase in fracture and all-cause mortality seems plausible, the association with cardiovascular events is surprising. The authors acknowledge that this finding was unexpected and could be due to residual confounding. One unmeasured factor that could explain this observation is smoking. A number of studies have shown that smokers are more likely to be prescribed opioids for chronic pain.2,3 Moreover, the association with smoking may be contributing to the observed increase in all-cause mortality and risk of fracture.4 Smoking is an important factor that needs to be taken into account when investigating these associations.
Rastegar DA. Safety of Opioids in Older Adults. Arch Intern Med. 2011;171(12):1126. doi:10.1001/archinternmed.2011.264