RESUMEN
Background: Omega-3 polyunsaturated fatty acids (PUFAs) have been associated with systemic anti-inflammatory responses. Dietary intake of omega-3 PUFAs eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has also been associated with lower chronic obstructive pulmonary disease (COPD) morbidity using self-report food frequency questionnaires. Objective: The objective of this study was to investigate the relationship between measured PUFA intake using plasma EPA+DHA levels and COPD morbidity. Methods: Former smokers with moderate-to-severe COPD living in low-income communities were enrolled in a 6-month prospective cohort study. Participants completed standardized questionnaires, spirometry, and plasma samples at 3-month intervals. Total plasma PUFAs were analyzed using gas chromatography/mass spectrometry for DHA and EPA concentrations. Linear or logistic mixed model regression was used to evaluate EPA+DHA's and COPD morbidity's association, accounting for demographics, lung function, pack years, comorbidities, and neighborhood poverty. Results: A total of 133 plasma EPA+DHA samples from 57 participants were available. Participants exhibited average plasma EPA and DHA levels of 14.7±7.3µg/mL and 40.2±17.2µg/mL, respectively, across the 3 clinic visits. Each standard deviation increase in EPA+DHA levels was associated with 2.7 points lower St George's Respiratory Questionnaire score (95% confidence interval [CI] -5.2, -0.2) and lower odds of moderate exacerbation (odds ratio 0.4; 95% CI 0.2, 0.9), but lacked significant association with the COPD Assessment Test score (95% CI -2.4, 0.8), modified Medical Research Council dyspnea scale (95% CI -02, 0.2), or severe exacerbations (95% CI 0.3, 1.4). Conclusion: Plasma EPA+DHA levels are associated with better respiratory-specific quality of life and lower odds of moderate exacerbations in patients with moderate-to-severe COPD. Further research is warranted to investigate the efficacy of an omega-3 dietary intervention in the management of COPD morbidities.
RESUMEN
Asthma has striking disparities across ancestral groups, but the molecular underpinning of these differences is poorly understood and minimally studied. A goal of the Consortium on Asthma among African-ancestry Populations in the Americas (CAAPA) is to understand multi-omic signatures of asthma focusing on populations of African ancestry. RNASeq and DNA methylation data are generated from nasal epithelium including cases (current asthma, N = 253) and controls (never-asthma, N = 283) from 7 different geographic sites to identify differentially expressed genes (DEGs) and gene networks. We identify 389 DEGs; the top DEG, FN1, was downregulated in cases (q = 3.26 × 10-9) and encodes fibronectin which plays a role in wound healing. The top three gene expression modules implicate networks related to immune response (CEACAM5; p = 9.62 × 10-16 and CPA3; p = 2.39 × 10-14) and wound healing (FN1; p = 7.63 × 10-9). Multi-omic analysis identifies FKBP5, a co-chaperone of glucocorticoid receptor signaling known to be involved in drug response in asthma, where the association between nasal epithelium gene expression is likely regulated by methylation and is associated with increased use of inhaled corticosteroids. This work reveals molecular dysregulation on three axes - increased Th2 inflammation, decreased capacity for wound healing, and impaired drug response - that may play a critical role in asthma within the African Diaspora.