Folate intake, serum folate levels, and prostate cancer risk: a meta-analysis of prospective studies

BMC Public Health

Jie-Ning Wang⁴  Yu-Hao Zhou³  Ai-Qin Zhang⁵  Jing-Yang Huang¹  Yan Zheng²  Rong Wang¹ 

[1] Department of Urinary Surgery, Shanghai Seventh People’s Hospital, Shanghai, China;Department of Science, Shanghai Seventh People’s Hospital, Shanghai, China;Department of Rehabilitation Institute, Shanghai Seventh People’s Hospital, Shanghai, China;Shanghai Seventh People’s Hospital, Shanghai, China;Department of Nursing, Shanghai Seventh People’s Hospital, Shanghai, China

关键词: Meta-analysis;    Dose–response;    Prostate cancer;    Folate;   

Others  :  1091114
DOI  :  10.1186/1471-2458-14-1326

 received in 2014-05-07, accepted in 2014-12-15,  发布年份 2014

【 摘 要 】

Background

Studies have reported inconsistent results concerning the existence of associations of folate intake and serum folate levels with prostate cancer risk. This study sought to summarise the evidence regarding these relationships using a dose–response meta-analysis approach.

Methods

In January 2014, we performed electronic searches of PubMed, Embase, and the Cochrane Library to identify studies examining the effect of folate on the incidence of prostate cancer. Only prospective studies that reported effect estimates with 95% confidence intervals (CIs) of the incidence of prostate cancer for more than 2 categories of folate were included.

Results

Overall, we included 10 prospective studies reporting data on 202,517 individuals. High dietary folate intake had little or no effect on prostate cancer risk (risk ratio [RR] = 1.02; 95% CI = 0.95–1.09; P = 0.598). The dose–response meta-analysis suggested that a 100 μg per day increase in dietary folate intake has no significant effect on the risk of prostate cancer (RR = 1.01; 95% CI = 0.99–1.02; P = 0.433). However, high serum folate levels were associated with an increased risk of prostate cancer (RR = 1.21; 95% CI = 1.05–1.39; P = 0.008). The dose–response meta-analysis indicated that a 5 nmol/L increment of serum folate levels was also associated with an increased risk of prostate cancer (RR = 1.04; 95% CI = 1.00–1.07; P = 0.042).

Conclusions

Our study indicated that dietary folate intake had little or no effect on prostate cancer risk. However, increased serum folate levels have potentially harmful effects on the risk of prostate cancer.

【 授权许可】

   
2014 Wang et al.; licensee BioMed Central.

【 图 表 】

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