Dietary Surveys and Nutritional Epidemiology

Diet and risk of endometriosis in a population-based case–control study

Britton Trabert^a1a2a3 c1, Ulrike Peters^a1a4, Anneclaire J. De Roos^a1a2, Delia Scholes^a5 and Victoria L. Holt^a1a2

^a1 Department of Epidemiology, University of Washington, Seattle, WA 98195, USA

^a2 Epidemiology Research Unit, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA

^a3 Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD 20852, USA

^a4 Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA

^a5 Center for Health Studies, Group Health Cooperative, Seattle, WA 98101, USA

Abstract

Diet plausibly has a role in the aetiology of endometriosis through effects on steroid hormone levels; however, few published studies have examined the diet and endometriosis risk. We evaluated dietary risk factors for endometriosis in a population-based case–control study. Cases were 284 Group Health (GH) enrollees aged 18–49 years with newly diagnosed, surgically confirmed endometriosis between 1996 and 2001. Controls were 660 randomly selected age-matched female GH enrollees without a history of endometriosis. Nutrients and selected food groups were assessed using the Women's Health Initiative FFQ. OR of endometriosis risk associated with dietary exposures were estimated using unconditional logistic regression and adjusted for identified covariates. Increased total fat consumption was associated with decreased endometriosis risk (fourth quartile v. lowest: OR 0·5, 95 % CI 0·2, 1·0, P-trend = 0·12). Increased β-carotene consumption and servings/d of fruit were associated with increased risk (β-carotene third quartile v. lowest: OR 1·7, 95 % CI 1·1, 2·6; fourth quartile v. lowest: OR 1·6, 95 % CI 1·0, 2·5, P-trend 0·16; fruit >2 servings/d v. < 1: OR 1·5, 95 % CI 1·0, 2·3, P-trend = 0·04). We also found a suggestion of decreased endometriosis risk associated with the consumption of dairy products (2 servings/d v. ≤ 1: OR 0·6, >2 servings/d v. ≤ 1: OR 0·7), but this association was not statistically significant for the highest tertile. The present study suggests that specific dietary components may be associated with endometriosis risk.

(Received February 03 2010)

(Revised July 05 2010)

(Accepted August 20 2010)

(Online publication September 28 2010)

Key Words:

• Case–control studies;
• Population-based studies;
• Diet;
• Endometriosis

Correspondence:

^c1 Corresponding author: B. Trabert, fax +1 301 402 0916, email trabertbl@mail.nih.gov

Footnotes

Abbreviations: GH, Group Health