Keum, N, Lee, DH, Greenwood, DC et al. (2 more authors) (2014) Calcium intake and colorectal adenoma risk: Dose-response meta-analysis of prospective observational studies. International Journal of Cancer. ISSN 0020-7136
Abstract
Evidence from randomized controlled trials suggests that calcium may protect against recurrence of colorectal adenomas, which could lead to the subsequent prevention of cancer. Yet, because the trials used only a large single dose and were of small sizes, knowledge of the dose-response relationship and influence on high-risk adenomas is limited. To address these issues, we conducted linear and non-linear dose-response meta-analyses primarily based on prospective observational studies published up to July 2014 identified from PubMed and Embase. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated for total and supplemental calcium intake, respectively, using a random-effects model. For total calcium intake, summary RR for each 300mg/day increase was 0.95(95% CI=0.92-0.98; I(2) =45%; 8 studies with 11,005 cases; range of intake=333-2,229 mg/day). Evidence of non-linearity was indicated: approximately, compared to 550 mg/day of total calcium intake, the summary RR was 0.92(95% CI=0.89-0.94) at 1000 mg/day and 0.87(95% CI=0.84-0.90) at 1450 mg/day (Pnon -linearity <0.01). Associations were stronger for high-risk adenomas (≥1 cm in diameter, (tubulo)villous histology, dysplasia, or multiplicity): approximately, compared to 550 mg/day of total calcium intake, the summary RR was 0.77(95% CI=0.74-0.81) at 1000 mg/day and reduced to 0.69(95% CI=0.66-0.73) at 1450 mg/da (Pnon -linearity <0.01). For supplemental calcium intake, summary RR of total adenoma risk for each 300mg/day increase was 0.96(95% CI=0.93-0.99; I(2) =0%; 3 studies with 4,548 cases; range of supplementation=0-1,366 mg/day). In conclusion, calcium intake may continue to decrease the risk of adenomas, particularly high-risk adenomas, over a wide range of calcium intake.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2014, Wiley. This is an author produced version of a paper published in International Journal of Cancer. Uploaded in accordance with the publisher's self-archiving policy. This is the accepted version of the following article: Keum, N, Lee, DH, Greenwood, DC, Zhang, X and Giovannucci, EL (2014) Calcium intake and colorectal adenoma risk: Dose-response meta-analysis of prospective observational studies, International Journal of Cancer which has been published in final form at http://dx.doi.org/10.1002/ijc.29164 |
Keywords: | Calcium intake; colorectal adenomas; dose-response meta-analysis; prospective observational studies |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Medicine and Health (Leeds) > Institute of Molecular Medicine (LIMM) (Leeds) > Section of Epidemiology and Biostatistics (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 03 Sep 2014 12:26 |
Last Modified: | 22 Oct 2015 02:26 |
Published Version: | http://dx.doi.org/10.1002/ijc.29164 |
Status: | Published |
Publisher: | Wiley |
Refereed: | Yes |
Identification Number: | 10.1002/ijc.29164 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:80441 |