Exercise may reduce prostate Ca risk in Caucasians

A new study suggests that exercise may reduce Caucasian men's risk of developing prostate cancer.

And among Caucasian men who do have prostate cancer, exercise may reduce their risk of having more serious forms of the disease. The benefits do not seem to apply to African-American men, according to the study’s results, which were published online in Cancer (Feb. 11, 2013).

Previous research has linked exercise to a reduced risk of developing prostate cancer. Studies have also revealed that African-American men have an increased risk of developing and dying from prostate cancer compared with Caucasians. It is not clear whether exercise as a function of race plays any role in these disparities.

To investigate, senior author Lionel L. Bañez, MD, of the Durham Veterans Affairs Medical Center, Durham, NC, and colleagues asked 307 men (164 Caucasian; 143 African-American) undergoing a prostate biopsy to complete a survey that assessed their weekly exercise amounts. Exercise categories included sedentary, mildly active, moderately active, and highly active. Among Caucasians, men who were moderately or highly active were 53% less likely to have biopsy results indicating that they had prostate cancer compared with men who were sedentary or mildly active. There was no association between exercise amount and prostate cancer among African-American men.

The authors also looked to see whether exercise influenced the grade of tumors that were detected in men who did develop prostate cancer. Among men with cancer, those who exercised had a 13% reduced risk of having high-grade disease. When this relationship was further explored as a function of race, it remained significant in Caucasians but not in African Americans.

"These findings that African-American men may not benefit from exercise the way Caucasian men do could be a contributor to why African-American race is a risk factor for prostate cancer and aggressive prostate cancer. Further studies are needed to investigate the mechanism behind this racial disparity in deriving cancer-related benefits from exercise which disfavors African-American men," Dr. Bañez said.