Racial Differences in CT Phenotypes in COPD

Abstract

Background Whether African Americans (AA) are more susceptible to COPD than non-Hispanic Whites (NHW) and whether racial differences in disease phenotype exist is controversial. The objective is to determine racial differences in the extent of emphysema and airway remodeling in COPD. Methods First, 2,500 subjects enrolled in the COPDGene study were used to evaluate racial differences in quantitative CT (QCT) parameters of % emphysema, air trapping and airway wall thickness. Independent variables studied included race, age, gender, education, BMI, pack-years, smoking status, age at smoking initiation, asthma, previous work in dusty job, CT scanner and center of recruitment. Results Of the 1,063 subjects with GOLD Stage II-IV COPD, 200 self-reported as AA. AAs had a lower mean % emphysema (13.1 % vs. 16.1%, p = 0.005) than NHW and proportionately less emphysema in the lower lung zones. After adjustment for covariates, there was no statistical difference by race in air trapping or airway wall thickness. Measured QCT parameters were more predictive of poor functional status in NHWs compared to AAs. Conclusions AAs have less emphysema than NHWs but the same degree of airway disease. Additional factors not easily assessed by current QCT techniques may account for the poor functional status in AAs.

Sex-specific features of emphysema among current and former smokers with COPD

“…In a previous analysis among the first 2500 subjects from the COPDGene study, Hansel and colleagues observed that AA subjects had less overall emphysema, as well as less lower lobe emphysema than NHW (23). We demonstrate that the sex-based differences in emphysema are less marked in AA subjects but the trend is still present.…”

“…In addition, these trends have not been fully explored among African American populations. One study among a subset of subjects from COPDGene demonstrated that AA had less overall emphysema than NHW (23). A further analysis of emphysema differences within these subgroups and across different races is an essential step towards understanding how COPD can develop and progress by sex, insights which may inform sex-specific clinical care of patients.…”

Obvious emphysema on computed tomography during an acute exacerbation of chronic obstructive pulmonary disease predicts a poor prognosis

“…Third, the severity of emphysema differs among ethnic groups, even with similar lung function impairment. 25 The COPD patients with hereditary alpha-1 antitrypsin deficiency, who often manifest severe emphysema, are extremely rare in China. 26 Since we screened almost all AECOPD patients who visited our emergency department without selection, and the mortality was only a little lower than in other cohorts, 3,4,17 we consider that this cohort covered a wide range of GOLD categories and different degrees of emphysema.…”

Remodeling in Allergic Rhinitis. Adding New Data to an Old Debate

“…In a similar fashion, the role of asymptomatic viral infections may also have had important effects on a number of endpoints in studies of nasal remodeling (9). Finally, there may be genetically regulated differences in remodeling processes, related to race as well as other factors, as has been suggested in other airway diseases (10).…”