C25-12 Dietary Patterns and Asthma Endotypes in Puerto Rican Youth

Rationale Dietary patterns may influence the pathogenesis of childhood asthma, a heterogeneous syndrome comprising unique mechanisms or endotypes. To date, little is known about the relation between diet and asthma endotypes in children. We examined whether dietary patterns are associated with specific asthma endotypes in Puerto Rican youths, a group disproportionately affected with asthma. Methods Cross-sectional and longitudinal analyses of dietary patterns and asthma endotypes in 358 to 465 Puerto Rican youths who completed a first study visit at ages 6-14 years and a second study visit at ages 9 to 20 years, approximately 5.3 years apart. Diet was assessed with a 75-item food frequency questionnaire, and a dietary score, ranging from -2 (unhealthiest diet, high consumption of dairy and sweets/soda, low consumption of vegetables and grains) to + 2 (healthiest diet, high consumption of vegetables and grains and low consumption of dairy and sweets/soda) was developed based on 7 food groups. An unhealthy diet was defined as a nonpositive dietary score (-2 to 0). Based on nasal epithelial expression levels of 8 “signature genes” for T helper (T)2 and T17 immunity, 3 asthma endotypes were identified at the second study visit, as previously described: T2-high, T17-high, and T2-low/T17-low (Yue M et al, JAMA 2025). Multinomial regression was used for the multivariable analysis of an unhealthy diet and asthma endotypes. Results In a cross-sectional analysis of data from 478 participants at the second visit, each one-point increment in dietary score was associated with 28% decreased odds of T17-high asthma compared to controls (odds ratio [OR]=0.72, 95% confidence interval [CI]=0.55, 0.94), even after adjustment for early-life (in utero or in the first two years of life) exposure to second-hand smoke, body mass index z-score, residential distance to a major road, and other covariates (see Table). Further, an unhealthy diet was associated with 2.25 times higher odds of T17-high asthma (95% CI = 1.28, 3.94) compared to controls. In a multivariable longitudinal analysis including 356 youths who completed both visits, a persistent unhealthy diet at both visits was associated with 4.31 times increased odds of T17-high asthma and 2.49 times increased odds of T2-low/T17-low asthma compared to controls. Conclusion In Puerto Rican youth, a persistently unhealthy diet in two study visits conducted ∼5 years apart was associated with increased odds of T17 high asthma and T2-low/T17-low asthma, suggesting that diet may influence asthma through non-T2-mediated immune pathways.