Dietary Patterns and Lung Function: Assessment of the Alternative Health Eating Index‐2010 (AHEI‐2010) and Rate of Change in Forced Expiratory Volume in the First Second (FEV1)

Abstract

ObjectivePrior studies of diet and lung function focus on individual nutrients or foods, whereas US Dietary Guidelines focus on dietary patterns. We investigated the association of the Alternative Healthy Eating Index‐2010 (AHEI‐2010), a measure of overall dietary quality and compliance to the US dietary guidelines, and lung function, quantified by the rate of change in forced expiratory volume in the first second (FEV1).MethodsThe Respiratory Ancillary Study (RAS; N=2,920), which was nested within SELECT (Selenium and Vitamin E Cancer Prevention Trial), studied the effect of supplementation with vitamin E and selenium on the longitudinal trajectory in lung function. RAS also assessed usual dietary intake with a food frequency questionnaire (FFQ) at study baseline; the current analysis investigated the AHEI‐2010 score (higher score indicates greater compliance to dietary guidelines), derived from the FFQ, in relation to rate of change in FEV1. Linear mixed‐effects models estimated the AHEI‐2010—rate of change in FEV1 association, with AHEI‐2010 as a continuous variable (null hypothesis β=0). Models were adjusted for race, age, height, weight, smoking status and pack‐years, education, marital status, residence status, treatment arm, multivitamin use, and energy intake, and extended to test the AHEI‐2010 score × smoking interaction.ResultsA higher AHEI‐2010 score was associated with a slower rate of decline in FEV1 across the full cohort such that an increase of 10 (~1SD) in AHEI‐2010 was associated with a 7.0 mL/year attenuation in the rate of decline (P=0.0009). Models confirmed a statistically significant interaction of AHEI‐2010 and smoking status (P=0.0278), which indicated a stronger association of AHEI‐2010—rate of decline in FEV1 in current smokers compared to never/former smokers. In current smokers, an increase of 10 (~1SD) in AHEI‐2010 was associated with a 17 mL/year attenuation in the annual decline in FEV1 (95% CI: 7, 26); in never/former smokers the same increase in AHEI‐2010 was associated with a 5mL/year (95% CI: 0.4, 9) attenuation in rate of decline.ConclusionsIn a population of North American men, a higher AHEI‐2010 score was associated with a slower decline in lung function, and the association was 3‐fold stronger in current smokers compared to never/former smokers. Translating this to dietary intake, in smoking men consuming one additional serving of vegetables or fruit/day (i.e., increase of 2 in AHEI‐2010), the annual rate of decline in FEV1 was attenuated by 3.3 mL/year.Support or Funding InformationFunding: NHLBI R01HL071022 (PAC), and, in part, by NCI U10CA37429 and 5UM1CA182883