Abstract 1911: Dietary intake of riboflavin and risk of lung cancer among non-smokers: A prospective cohort study among Chinese women

Abstract

Abstract Lung cancer is the leading cause of cancer death in the United States and many other countries. A significant subset of lung cancers is not associated with smoking, and risk factors for these cancers remain unclear. Riboflavin (vitamin B2), a water-soluble vitamin, is involved in vital metabolic processes and is necessary for normal cell function, growth, and energy production. Riboflavin is the central component of the flavin mononucleotide (FMN) and flavin dinucleotide (FAD), coenzymes for a wide variety of oxidative enzymes. We prospectively examined the association of dietary intake of riboflavin with lung cancer risk in the Shanghai Women's Health Study cohort. A total of 73,237 women aged 40-70 years and free of cancer at enrollment were included in this analysis. Usual dietary intake was assessed at baseline (1997-2000) through in-person interviews by using a validated food-frequency questionnaire. We used Cox proportional hazards regression to estimate the relative risks (RR) and 95% confidence intervals (CI) for the association of lung cancer risk with dietary riboflavin consumption. In 665,554 person-years of follow-up, we identified 328 lung cancer cases, of which 303 were non-smokers. Dietary intake of riboflavin was inversely associated with lung cancer risk. The RRs (95% CI) of developing lung cancer among non-smokers decreased with increasing quintiles of riboflavin intake (P for trend = 0.007) from 1.0 to 1.01 (0.73-1.42), 0.77 (0.53-1.13), 0.81 (0.55-1.20), and 0.51 (0.31-0.83) for the lowest to highest quintiles. Exclusion of 51 cases diagnosed within two years of follow-up did not change the HR estimations appreciably. Further, adjusting for dietary intakes of other B vitamins (B1, B6, B12, niacin, and folate) and methionine did not meaningfully affect the HR estimates. No statistically significant associations were found for other B vitamins. In summary, our findings among non-smoking Chinese women suggest that dietary intake of riboflavin may reduce the risk of lung cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1911. doi:10.1158/1538-7445.AM2011-1911