Originally published as JCO Early Release 10.1200/JCO.2008.20.0493 on August 17 2009

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Google Scholar Articles by Caan, B. J. Articles by Ockene, J. PubMed PubMed Citation Articles by Caan, B. J. Articles by Ockene, J. Social Bookmarking                            What's this?

Vasomotor Symptoms, Adoption of a Low-Fat Dietary Pattern, and Risk of Invasive Breast Cancer: A Secondary Analysis of the Women's Health Initiative Randomized Controlled Dietary Modification Trial

From the Division of Research, Kaiser Permanente Northern California, Oakland; Stanford Prevention Research Center, Stanford University, Stanford; Harbor–University of California, Los Angeles Medical Center, Torrance; School of Medicine, University of California, Irvine, Irvine, CA; Fred Hutchinson Cancer Center, Seattle, WA; Department of Nutritional Sciences, Arizona Cancer Center, University of Arizona, Tucson, AZ; Wake Forest University, Winston Salem, NC; Baylor College of Medicine, San Antonio, TX; Brigham Women's Hospital, Boston; and University of Massachusetts Medical School, Worcester, MA.

Corresponding author: Bette Caan, DrPH, Division of Research, Kaiser Permanente, 2000 Broadway, Oakland, CA 94612; e-mail: bette.caan{at}kp.org.

Purpose To assess whether the effect of a low-fat dietary pattern on breast cancer incidence varied by report of baseline vasomotor symptoms.

Methods Postmenopausal women age 50 to 79 years enrolled onto the Women's Health Initiative (WHI) Dietary Modification trial from 1993 to 1998 were randomly assigned to a low-fat dietary intervention (n = 19,541) or comparison (n = 29,294). Presence of vasomotor symptoms at baseline was ascertained from a 34-item self-report symptom inventory. Women were queried semi-annually for a new diagnosis of breast cancer. Each case report was verified by medical record and pathology report review by centrally trained WHI physician adjudicators.

Results Among participants who reported hot flashes (HFs) at baseline (n = 3,375), those assigned to the low-fat diet had a breast cancer rate of 0.27 compared with their counterparts in the control group who had a rate of 0.41 (hazard ratio [HR] = 0.65; 95% CI, 0.42 to 1.01). Among women reporting no HFs (n = 45,160), the breast cancer rate was 0.42 in those assigned to the low-fat diet compared with 0.46 in the control group (HR = 0.93; 95% CI, 0.84 to 1.03; P for interaction = .12 by HF status). Furthermore, the dietary benefits observed seemed to be specific to estrogen receptor (ER) –positive/progesterone receptor (PR) –positive tumors (ER positive/PR positive v other, P for risk = .03). Although women with and without HFs differed with regard to breast cancer risk factors, the effect of the diet intervention on breast cancer incidence by HF status was consistent across risk factor strata.

Conclusion The results of this trial, which are hypothesis generating, suggest that HFs may identify a subgroup of postmenopausal women whose risk of invasive breast cancer might be reduced with the adoption of a low-fat eating pattern.

The Women's Health Initiative was supported by the National Heart, Lung, and Blood Institute (C.A.T.); the Women's Healthy Eating and Living study was supported by the National Cancer Institute (C.A.T.).

Authors' disclosures of potential conflicts of interest and author contributions are found at the end of this article.

Clinical Trials repository link available on JCO.org.

Clinical trial information can be found for the following: NCT00000611 [ClinicalTrials.gov] .

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?