Partnerships for promoting prevention.

I n an elegant analysis from the Atherosclerosis Risk in Communities Study, Rasmussen-Torvik and colleagues demonstrate that a higher degree of adherence to the American Heart Association's 7 health and behavior factors recommended for prevention of cardiovascular disease was also related to substantially reduced incidence of cancer, over a 17-to 19-year follow-up. 1 As one might expect, the strongest common risk factor for these 2 leading causes of death is smoking. Although it is more strongly associated with lung cancer (in terms of relative risk) than with cardiovascular disease, smoking causes more deaths from cardiovascular disease. However, even after excluding smoking from the 7 factors, those meeting the goals for 5 to 6 of these health metrics had a significant 25% lower risk of cancer in comparison with those who met none of the goals. The authors expressed surprise to observe a significant trend for increased prostate cancer incidence among men with a larger number of ideal health metrics. The most likely explanation for this entirely predictable result is that health consciousness – including greater adherence to the ideal health metrics – is associated with more prostate-specific antigen screening. It is not widely appreciated that a large fraction, perhaps even a majority, of older men in the United States harbor undiagnosed prostate cancer. As an illustration, in 2 large randomized trials of low-risk (prostate-specific antigen <3 at baseline) middle-aged men, random biopsies were conducted after 4 and 7 years of follow-up; in the placebo arms of those trials, 25% of the men were diagnosed with prostate cancer, almost entirely low-grade and early-stage disease. 2,3 Similarly, autopsy studies of men with no previous symptoms of pros-tate cancer show an age-related prevalence of undiagnosed prostate cancer that exceeds 50% in the oldest age groups in some studies. 4 Thus, the major risk factor for the diagnosis of prostate cancer is getting a biopsy after screening. For this reason, epidemiological studies of total prostate cancer incidence are difficult to interpret in the era of prostate-specific antigen screening, and the focus of such a study should be on lethal disease. 5 The investigators were unable to evaluate advanced or fatal prostate cancer, but they note substantial evidence that smoking is a strong risk factor for fatal prostate cancer. 6 The apparent relation of smoking with lower risk of nonadvanced prostate cancer in that same study is likely an artifact of less prostate-specific antigen screening …