The Aspirin/Folate Polyp Prevention Study (AFPPS) involved two comparisons in patients with recently resected colorectal adenomas — aspirin versus placebo and folic acid versus placebo (JW Mar 19 2009). Previously published results from the folic acid portion of the study indicated that daily supplementation (1 mg) did not prevent recurrent colorectal adenomas; in fact, investigators found a nonsignificant trend toward more high-grade adenomas in the folic acid group (2007). Now, the researchers report on another outcome — prostate cancer — among 643 participating men (mean age at enrollment, 57).
During a median follow-up of 7 years, prostate cancer was diagnosed in 25 folic acid recipients and in 9 placebo recipients. The estimated 10-year probability of prostate cancer was significantly higher in the folic acid group than in the placebo group (9.7% vs. 3.3%).
Comments: So men who took folic acid daily were more likely to develop cancer during 7 years of follow-up, almost 3-to-1. The etiology is unclear _ BA