Dose-response meta-analysis of poultry intake and colorectal cancer incidence and mortality.
OBJECTIVE
Poultry intake has been inconsistently associated with incidence or mortality of colorectal cancer (CRC) in epidemiologic studies. The purpose of this study was to assess their relationships by performing a dose-response meta-analysis.


METHODS
We conducted a search of PubMed database between January 1966 and July 2013 for prospective studies that reported relative risks (RRs) with 95 % confidence interval (CIs) of CRC for at least three categories of poultry intake. Dose-response relationships were examined with the generalized least-squares trend estimation. Study-specific results were pooled with a random-effects model. Subgroup, sensitivity, and meta-regression analyses were also conducted to explore heterogeneity.


RESULTS
Sixteen studies on poultry intake and CRC incidence, and four studies regarding poultry intake and CRC mortality were identified. These studies involved a total of 13,949 incident CRC cases and 983 CRC deaths. The RRs of CRC for higher compared with lower intake of poultry were reported in these studies, and the reported levels of poultry intake varied substantially. Results of the dose-response meta-analysis conferred a RR of 0.89 (95 % CI 0.81-0.97) for an increase in poultry intake of 50 g/day. The results were not sensitive to any individual studies and were similar for colon and rectal cancer. Poultry intake was not associated with CRC mortality (RR for 50 g/day = 0.97, 95 % CI 0.79-1.20).


CONCLUSIONS
This meta-analysis indicates that poultry intake may be moderately associated with reduced incidence of CRC.
Department of General Surgery and Center of Minimal Invasive Gastrointestinal Surgery, Southwest Hospital, The Third Military Medical University, Gaotanyan Street 30#, Shapingba District, Chongqing, 400038, China.
Yan
Y
Shi
Pei-Wu
PW
Yu
Dong-Zhu
DZ
Zeng
D000818:Animals; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000401:mortality / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D008460:Meat / Q000009:adverse effects*; D011200:Poultry; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D015203:Reproducibility of Results; D012306:Risk