Journal article
Nitrate and nitrite ingestion and risk of ovarian cancer among postmenopausal women in Iowa
International journal of cancer, Vol.137(1), pp.173-182
12/08/2014
DOI: 10.1002/ijc.29365
PMCID: PMC4405451
PMID: 25430487
Abstract
Nitrate and nitrite are precursors in the endogenous formation of
N
-nitroso compounds (NOC), potential human carcinogens. We evaluated the association of nitrate and nitrite ingestion with postmenopausal ovarian cancer risk in the Iowa Women’s Health Study. Among 28,555 postmenopausal women, we identified 315 incident epithelial ovarian cancers from 1986 to 2010. Dietary nitrate and nitrite intakes were assessed at baseline using food frequency questionnaire data. Drinking water source at home was obtained in a 1989 follow-up survey. Nitrate-nitrogen (NO
3
-N) and total trihalomethane (TTHM) levels for Iowa public water utilities were linked to residences and average levels were computed based on each woman’s duration at the residence. We computed multivariable-adjusted hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazards regression. We tested interactions of nitrate with TTHMs and dietary factors known to influence NOC formation. Ovarian cancer risk was 2.03 times higher (CI=1.22–3.38,
p
trend
=0.003) in the highest quartile (≥2.98 mg/L) compared with the lowest quartile (≤0.47 mg/L; reference) of NO
3
-N in public water, regardless of TTHM levels. Risk among private well users was also elevated (HR=1.53, CI=0.93–2.54) compared with the same reference group. Associations were stronger when vitamin C intake was <median (
p
interaction
=0.01 and 0.33 for private well and public supplies, respectively). Dietary nitrate was inversely associated with ovarian cancer risk (
p
trend
=0.02); whereas, dietary nitrite from processed meats was positively associated with the risk (
p
trend
=0.04). Our findings indicate that high nitrate levels in public drinking water and private well use may increase ovarian cancer risk among postmenopausal women.
Details
- Title: Subtitle
- Nitrate and nitrite ingestion and risk of ovarian cancer among postmenopausal women in Iowa
- Creators
- Maki Inoue-Choi - University of IowaRena R. Jones - National Institutes of HealthKristin E. Anderson - University of MinnesotaKenneth P. Cantor - National Institutes of HealthJames R. Cerhan - Mayo ClinicStuart Krasner - Metropolitan Water District of Southern CaliforniaKim Robien - University of IowaPeter J. Weyer - University of IowaMary H. Ward - National Institutes of Health
- Resource Type
- Journal article
- Publication Details
- International journal of cancer, Vol.137(1), pp.173-182
- DOI
- 10.1002/ijc.29365
- PMID
- 25430487
- PMCID
- PMC4405451
- ISSN
- 0020-7136
- eISSN
- 1097-0215
- Grant note
- name: National Cancer Institute of the National Institutes of Health, award: R01 CA039742 (to K.A. and K.R.); name: Intramural Research Program of the National Cancer Institute (M.I-C., R.J., K.C., M.W.); name: Division of Intramural Research of the National Institute on Minority Health and Health Disparities of the National Institutes of Health (M.I.-C.)
- Language
- English
- Date published
- 12/08/2014
- Academic Unit
- Occupational and Environmental Health; Epidemiology
- Record Identifier
- 9984368090302771
Metrics
11 Record Views