ma Coenzyme Q 10 Levels and Postmenopausal Breast B & P cer Risk : The Multiethnic Cohort Study

ownloade kground: Coenzyme Q10 (CoQ10) is a component of the mitochondrial electron transport chain and is ered an important cellular antioxidant. Decreased circulating CoQ10 levels have been reported in n with breast cancer, but evidence is limited. We examined the association of plasma CoQ10 levels with enopausal breast cancer risk using prospectively collected blood samples. thods: Prediagnostic plasma levels of total CoQ10 were measured among 160 incident postmenopausal cancer cases and 289 controls in the Multiethnic Cohort Study. Cases and controls were individually ed on age, sex, ethnicity, study location (Hawaii or California), hormone replacement therapy use, date me of specimen collection, and hours of fasting. Logistic regression was used to compute odds ratios % confidence intervals. ults: Plasma CoQ10 levels were positively associated with breast cancer risk, overall (P = 0.04). The ation was stronger after women diagnosed within 1 year of blood draw were excluded to eliminate le preclinical cases (odds ratio for the highest versus the lowest tertile, 2.26; 95% confidence interval, .19; P for trend = 0.01). clusions: Higher CoQ10 levels in postmenopausal women may be associated with increased breast risk. act: A potential role for CoQ10 in the development and progression of breast cancer has been postubut epidemiologic evidence is lacking. Findings from this prospective cohort study add to the limited lated, literature, indicating the potential positive association of circulating CoQ10 with postmenopausal breast cancer risk. Cancer Epidemiol Biomarkers Prev; 19(9); 2351–6. ©2010 AACR.