HealthDay News — Exercising may cut the risk of developing prostate cancer and lower the risk for high-grade disease among white men, study results show.
In a prospective study, men who scheduled a biopsy for suspected prostate cancer were less likely to have the disease if they were at least moderately active, Lionel Bañez, MD, of the Durham Veterans Affairs Medical Center in Durham N.C., and colleagues.
Those who did have prostate cancer were significantly less likely to have high-grade disease if they exercised regularly, the researchers reported in Cancer. However, for reasons not yet understood, neither of these protective effects were observed in black men.
Bañez and colleagues surveyed 307 men — 164 white and 143 black — who were undergoing prostate biopsy to assess exercise behavior. The questionnaire grouped participants’ exercise level in four categories of metabolic equivalent (MET) hours per week: sedentary was defined as fewer than three hours, 3 through 8.9 hours was considered mildly active, 9 through 17.9 was moderately active, and 18 or more was highly active.
Average patient age was 64 years, and between racial groups there was no significant difference in the amount of exercise. A total of 125 men were diagnosed with prostate cancer after biopsy, including 54 with high-grade disease.
In both crude and adjusted models, higher amounts of MET hours per week correlated with a decreased risk of prostate cancer for white men, but not black men. Compared with white men who exercised less than nine MET hours per week, those who exercised for nine or more MET hours per week were significantly less likely to have a positive biopsy result (OR= 0.47; 95% CI: 0.22-0.99; P=0.047).
“These results support a growing library of data indicating that exercise can be associated with [prostate cancer] risk reduction,” the researchers wrote. “However, the current study also demonstrates that further investigation is necessary to understand the intricacies of this relationship, specifically with regard to race.”
Study limitations include the small cohort size, which increases the likelihood of chance findings, and the potential for unmeasured factors, such as diet, that may have influenced outcomes.