Late-breaking abstract: Dietary flavonoids, ventilatory function and lung obstruction in adults across Europe – a GA ² LEN study

Background Dietary flavonoids have antioxidant and anti-inflammatory effects which might protect the lungs, but epidemiological evidence is scant. We investigated the association between flavonoids and lung function in European adults. Methods A stratified random sample was drawn from the GA 2 LEN screening survey, in which 55,000 adults aged 15 to 75 answered a questionnaire on respiratory symptoms. Post-bronchodilator spirometry was obtained from 2,810 subjects. Forced vital capacity (FVC), the ratio between the forced exhaled volume in 1 second (FEV 1 ) and FVC (FEV 1 /FVC), FVC below lower limit of normal (FVC<LLN) and FEV 1 /FVC<LLN were calculated. Intake of 6 major classes of flavonoids was estimated using the GA 2 LEN FFQ. Associations between outcomes and flavonoids were examined with regression and meta-analyses. Simes procedure was used to adjust for multiple comparisons. Results FVC (Lt) was associated with anthocyanin intake (Adjusted [a] b-coeffient of higher vs. lowest quintile intake 0.16; 95% Confidence Interval [CI] 0.06 to 0.26) and with flavone intake (ab-coefficent 0.19; 95% CI 0.09 to 0.28). A lower risk of having an FVC < LLN was observed in those with a higher intake of flavones (Odds Ratio [aOR] 0.43; 0.23 to 0.83). The risk of having an FEV 1 /FVC < LLN was lower in those with highest intakes of Flavan3ols (aOR 0.37; 95% CI 0.15 to 0.92). After controlling for multiple comparisons, only the associations with FVC remained statistically significant. Conclusion This first epidemiological study on all major flavonoid subclasses and lung function and obstruction provides evidence for a protective effect of anthocyanins on lung function in adults.