Importance People who smoked cigarettes may experience respiratory symptoms without spirometric airflow obstruction. These individuals are typically excluded from chronic obstructive pulmonary disease (COPD) trials and lack evidence-based therapies. Objective To define the natural history of persons with tobacco exposure and preserved spirometry (TEPS) and symptoms (symptomatic TEPS). Design, Setting, and Participants SPIROMICS II was an extension of SPIROMICS I, a multicenter study of persons aged 40 to 80 years who smoked cigarettes (>20 pack-years) with or without COPD and controls without tobacco exposure or airflow obstruction. Participants were enrolled in SPIROMICS I and II from November 10, 2010, through July 31, 2015, and followed up through July 31, 2021. Exposures Participants in SPIROMICS I underwent spirometry, 6-minute walk distance testing, assessment of respiratory symptoms, and computed tomography of the chest at yearly visits for 3 to 4 years. Participants in SPIROMICS II had 1 additional in-person visit 5 to 7 years after enrollment in SPIROMICS I. Respiratory symptoms were assessed with the COPD Assessment Test (range, 0 to 40; higher scores indicate more severe symptoms). Participants with symptomatic TEPS had normal spirometry (postbronchodilator ratio of forced expiratory volume in the first second [FEV 1 ] to forced vital capacity >0.70) and COPD Assessment Test scores of 10 or greater. Participants with asymptomatic TEPS had normal spirometry and COPD Assessment Test scores of less than 10. Patient-reported respiratory symptoms and exacerbations were assessed every 4 months via phone calls. Main Outcomes and Measures The primary outcome was assessment for accelerated decline in lung function (FEV 1 ) in participants with symptomatic TEPS vs asymptomatic TEPS. Secondary outcomes included development of COPD defined by spirometry, respiratory symptoms, rates of respiratory exacerbations, and progression of computed tomographic–defined airway wall thickening or emphysema. Results Of 1397 study participants, 226 had symptomatic TEPS (mean age, 60.1 [SD, 9.8] years; 134 were women [59%]) and 269 had asymptomatic TEPS (mean age, 63.1 [SD, 9.1] years; 134 were women [50%]). At a median follow-up of 5.76 years, the decline in FEV 1 was −31.3 mL/y for participants with symptomatic TEPS vs −38.8 mL/y for those with asymptomatic TEPS (between-group difference, −7.5 mL/y [95% CI, −16.6 to 1.6 mL/y]). The cumulative incidence of COPD was 33.0% among participants with symptomatic TEPS vs 31.6% among those with asymptomatic TEPS (hazard ratio, 1.05 [95% CI, 0.76 to 1.46]). Participants with symptomatic TEPS had significantly more respiratory exacerbations than those with asymptomatic TEPS (0.23 vs 0.08 exacerbations per person-year, respectively; rate ratio, 2.38 [95% CI, 1.71 to 3.31], P < .001). Conclusions and Relevance Participants with symptomatic TEPS did not have accelerated rates of decline in FEV 1 or increased incidence of COPD vs those with asymptomatic TEPS, but participants with symptomatic TEPS did experience significantly more respiratory exacerbations over a median follow-up of 5.8 years.
A Polygenic Risk Score for Idiopathic Pulmonary Fibrosis and Interstitial Lung Abnormalities
Abstract Rationale In addition to rare genetic variants and the MUC5B locus, common genetic variants contribute to idiopathic pulmonary fibrosis (IPF) risk. The predictive power of common variants outside the MUC5B locus for IPF and interstitial lung abnormalities (ILAs) is unknown. Objectives We tested the predictive value of IPF polygenic risk scores (PRSs) with and without the MUC5B region on IPF, ILA, and ILA progression. Methods We developed PRSs that included (PRS-M5B) and excluded (PRS-NO-M5B) the MUC5B region (500-kb window around rs35705950-T) using an IPF genome-wide association study. We assessed PRS associations with area under the receiver operating characteristic curve (AUC) metrics for IPF, ILA, and ILA progression. Measurements and Main Results We included 14,650 participants (1,970 IPF; 1,068 ILA) from six multi-ancestry population-based and case–control cohorts. In cases excluded from genome-wide association study, the PRS-M5B (odds ratio [OR] per SD of the score, 3.1; P = 7.1 × 10−95) and PRS-NO-M5B (OR per SD, 2.8; P = 2.5 × 10−87) were associated with IPF. Participants in the top PRS-NO-M5B quintile had ∼sevenfold odds for IPF compared with those in the first quintile. A clinical model predicted IPF (AUC, 0.61); rs35705950-T and PRS-NO-M5B demonstrated higher AUCs (0.73 and 0.7, respectively), and adding both genetic predictors to a clinical model yielded the highest performance (AUC, 0.81). The PRS-NO-M5B was associated with ILA (OR, 1.25) and ILA progression (OR, 1.16) in European ancestry participants. Conclusions A common genetic variant risk score complements the MUC5B variant to identify individuals at high risk of interstitial lung abnormalities and pulmonary fibrosis.
Risk Factors for Symptomatic SARS-CoV2 Infection, Severe COVID-19, and Vaccination Response in the Severe Asthma Research Program
B15. ASTHMA: HOT OFF THE PRESS FROM THE BENCH TO THE CLINIC | May 1, 2023 | Volume: No volume available | Issue: No issue available | Pages: A2766-A2766
Abstract Background Asthma exacerbations are a serious public health concern due to high healthcare resource utilization, work/school productivity loss, impact on quality of life, and risk of mortality. The genetic basis of asthma exacerbations has been studied in several populations, but no prior study has performed a multi‐ancestry meta‐analysis of genome‐wide association studies (meta‐GWAS) for this trait. We aimed to identify common genetic loci associated with asthma exacerbations across diverse populations and to assess their functional role in regulating DNA methylation and gene expression. Methods A meta‐GWAS of asthma exacerbations in 4989 Europeans, 2181 Hispanics/Latinos, 1250 Singaporean Chinese, and 972 African Americans analyzed 9.6 million genetic variants. Suggestively associated variants ( p ≤ 5 × 10 −5 ) were assessed for replication in 36,477 European and 1078 non‐European asthma patients. Functional effects on DNA methylation were assessed in 595 Hispanic/Latino and African American asthma patients and in publicly available databases. The effect on gene expression was evaluated in silico. Results One hundred and twenty‐six independent variants were suggestively associated with asthma exacerbations in the discovery phase. Two variants independently replicated: rs12091010 located at vascular cell adhesion molecule‐1/exostosin like glycosyltransferase‐2 ( VCAM1 / EXTL2 ) (discovery: odds ratio (OR T allele ) = 0.82, p = 9.05 × 10 −6 and replication: OR T allele = 0.89, p = 5.35 × 10 −3 ) and rs943126 from pantothenate kinase 1 ( PANK1 ) (discovery: OR C allele = 0.85, p = 3.10 × 10 −5 and replication: OR C allele = 0.89, p = 1.30 × 10 −2 ). Both variants regulate gene expression of genes where they locate and DNA methylation levels of nearby genes in whole blood. Conclusions This multi‐ancestry study revealed novel suggestive regulatory loci for asthma exacerbations located in genomic regions participating in inflammation and host defense.
DNA Sequencing Analysis of Cystic Fibrosis Transmembrane Regulator Gene Identifies Cystic Fibrosis-Associated Variants in the Severe Asthma Research Program
B60. ASTHMA AND ALLERGIC RESPONSES: CELLS, TISSUES, AND ANIMAL MODELS | May 2, 2022 | Volume: No volume available | Issue: No issue available | Pages: A3244-A3244
B101. VARIED OMICS TECHNIQUES APPLIED TO ALLERGIC AND RESPIRATORY TRAITS | May 2, 2022 | Volume: No volume available | Issue: No issue available | Pages: A3472-A3472
DNA sequencing analysis of cystic fibrosis transmembrane conductance regulator gene identifies cystic fibrosis‐associated variants in the Severe Asthma Research Program
AbstractBackgroundHeterozygote carriers of potentially pathogenic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have increased asthma risk. However, the frequency and impact of CFTR variation among individuals with asthma is unknown.ObjectiveTo determine whether potentially pathogenic CFTR variants associate with disease severity and whether individuals with two potentially pathogenic variants exist in a severe asthma‐enriched cohort.MethodsWe analyzed sequencing data spanning a 190.5Kb region of CFTR in participants from the Severe Asthma Research Program (SARP1‐3). Potentially pathogenic, rare CFTR variants (frequency < 0.05) were classified as CF‐causing or of varying clinical consequences (VVCC) (CFTR2. org). Regression‐based models tested for association between CFTR genotypes (0‐2 potentially pathogenic variants) and severity outcomes.ResultsOf 1401 participants, 9.5% (134) had one potentially pathogenic variant, occurring more frequently in non‐Hispanic white (NHW, 10.1% [84 of 831]) compared to African American individuals (AA, 5.2% [22 of 426]). We found ≥2 potentially pathogenic CFTR variants in 1.4% (19); 0.5% (4) of NHW and 2.8% (12) of AA. Potentially pathogenic CFTR variant genotypes (≥1 or ≥2 variants) were not cumulatively associated with lung function or exacerbations. In NHW, we found three F508del compound heterozygotes with F508del and a VVCC (two 5 T; TG12[c.1210‐11 T > G] and one Arg1070Trp) and a homozygote for the VVCC, 5 T; TG12.ConclusionsWe found potentially pathogenic CFTR variants within a severe asthma‐enriched cohort, including three compound heterozygote genotypes variably associated with CF in NHW individuals. These findings provide the rationale for CFTR sequencing and phenotyping of CF‐related traits in individuals with severe asthma.