Overweight and obese men carry lower concentrations of prostate-specific antigen (PSA) than average-weight men, a finding
from an earlier study that researchers at Duke University Medical Center have confirmed in the wider population. Researchers
sought to determine whether high, early-life body mass index (BMI) correlated with current BMI and the results of PSA tests
and digital rectal examination for prostate abnormalities. They found that higher BMI did associate with lower PSA values—mildly
and moderately-to-severely obese men had PSA scores 14% and 29% lower, respectively, than normal-weight men—but that weight
had no significant association with digital exam findings. The researchers believe the greater blood volume of obese men dilutes
their PSA levels, which—combined with evidence of greater posttreatment cancer progression and mortality in obese men—may
lead doctors to miss positive cancer diagnoses and delay treatment. They conclude that the PSA threshold for a positive result
should be adjusted for the patient's obesity level, and that all patients should pursue healthy lifestyles and be screened
regularly to cut their odds of developing advanced prostate cancer.
http://Eurekalert.org/. "Overweight and obese men have lower PSA values, even before they get prostate cancer." 2008. http://www.eurekalert.org/pub_releases/2008-02/dumc-oao021908.php (11 Mar. 2008).
Price, M. M., Hamilton, R. J., et al. "Body mass index, prostate-specific antigen, and digital rectal examination findings
among participants in a prostate cancer screening clinic." 2008. http://www.goldjournal.net/article/S0090-4295(07)02407-7/fulltext/ (11 Mar. 2008).