By David Liu, Ph.D.

Sunday June 26, 2011 (foodconsumer.org) -- A new study in the June 22/29 2011 issue of JAMA suggests men smoking at the time of diagnosis of prostate cancer, defined as current smokers, may boost their risk of dying from the disease and cardiovascular disease.

The study shows current smokers with prostate cancer were 61 percent more likely to die from the disease, compared with those who never smoked.

Additionally, smokers with prostate cancer were also 61 percent more likely to have recurrence, 128 percent more likely to die from all causes, and 113 percent more likely to die from cardiovascular disease.

Edward Giovannucci of Harvard School of Public Health and colleagues found these associations after analyzing data from 5,366 men diagnosed with prostate cancer from 1986 through 2006 who were enrolled in the Health Professionals Follow-up Study.

The recurrence or so called biochemical recurrence was defined by an increase in prostate-specific antigen concentrations, which indicate the risk of prostate cancer.

During the follow-up, the rates of death from prostate cancer were 9.6 per 1000 person-years for never-smokers and  15.3 per person-years for current smokers.  The rates of all-cause deaths were 27.3 and 53.0 per person-years for never smokers and current smokers respectively. 

After adjustment for other factors, current smokers increased their risk of prostate cancer death by 38 percent and recurrence by 47 percent.

The more cigarettes men smoked, the higher the risk of their dying from prostate cancer.  The researchers found current smokers who smoked 40 or more pack-year were 82 percent more likely to die from prostate cancer and 48 percent more likely to have recurrence, compared with those who never smoked.

Men who had quit smoking tobacco for ten or more years or quit for less than 10 years but smoked fewer than 20 pack-years were at a risk of dying from prostate cancer that was similar to that for current smokers.  The reduction in the risk was about 40 percent.

The researchers concluded that men who smoked may boost the risk of dying from prostate cancer and cardiovascular disease and quitting smoking for a long period may improve their prognosis. 

The study is observational and it does not prove that smoking per se increases the risk of early death from prostate cancer although it has been known for a long time that smoking is linked with elevated risk of death from cardiovascular disease.