Clinical Significance of Radiologic Characterizations in COPD

Abstract

COPD is a heterogeneous disorder with clinical assessment becoming increasingly multidimensional. We hypothesized HRCT phenotype would strongly influence clinical outcomes including health status, exacerbation frequency, and BODE. COPD subjects were characterized via the SF-12, SGRQ, MMRC, physiologic testing, and standardized volumetric chest HRCT. Visual semi-quantitative estimation of bronchial wall thickness (VBT) and automated quantification of emphysema percent and bronchial wall thickness were generated. Multivariate modeling compared emphysema severity and airway abnormality with clinical outcome measures. Poisson models were used to analyze exacerbation frequency. SGRQ and SF-12 physical component scores were influenced by FEV(1)% predicted, emphysema percent, and VBT. VBT scores > 2 (scale 0-48) were associated with increased exacerbation frequency (p = 0.009) in the preceding year adjusting for age, gender, emphysema percent, smoking history and FEV(1)% predicted, although this effect was attenuated by age. Emphysema percent correlated with total BODE score in unadjusted (r = 0.73; p < 0.0001) and adjusted (p < 0.0001) analyses and with BODE individual components. HRCT provides unique COPD phenotyping information. Radiographic quantification of emphysema and bronchial thickness are independently associated with SGRQ and physical component score of the SF-12. Bronchial thickness but not emphysema is associated with exacerbation frequency, whereas emphysema is a stronger predictor of BODE and its systemic components MMRC, 6MWT, and BMI. Future research should clarify whether CT parameters complement BODE score in influencing survival.

Chronic Obstructive Pulmonary Disease Exacerbations in the COPDGene Study: Associated Radiologic Phenotypes

“…Our study results corroborate our published preliminary fi ndings and the fi ndings of others ( 8,21 ). Airway infl ammation, as measured by using wall thickness at the segmental level, offers additional potentially important prognostic information beyond that assessed with spirometry alone.…”

“…We previously reported, for a small cohort of 34 patients, that a visual semiquantitative measurement of bronchial thickness was associated with increased COPD exacerbation frequency, after adjustment for FEV 1 percent predicted ( 8 ). However, it is unclear how these measures perform in a larger more diverse population of patients with COPD.…”

Disease severity and symptoms among patients receiving monotherapy for COPD

“…24 It is also becoming clear that CT scans can provide quantitative measures of both emphysema and airways disease and that each correlates with specific phenotypic characteristics. 25 Recent guidelines, including those published by the National Institute for Clinical Excellence in the UK, and the American, Canadian and European Thoracic Societies, have increasingly recognised the need to incorporate non-spirometric measures in assessing COPD and determining appropriate therapy. 22,26,27 These guidelines support the prescription of additional therapies for patients with ongoing respiratory symptoms and poor quality of life independent of lung function impairment.…”

Clinical Characteristics of Patients With Chronic Obstructive Pulmonary Disease With Comorbid Bronchiectasis: A Systemic Review and Meta-analysis

“…An emerging area of COPD phenotype research is the use of radiologic imaging to categorize patients into different phenotypes based on the degree of emphysema and bronchial wall thickening, a prominent imaging feature of bronchiectasis. 1,11,[25][26][27] The "emphysema hyperinflation phenotype" was relatively well established in previous studies, defining patients with COPD who present with dyspnea and intolerance to exercise as the predominating symptoms, accompanied by signs of hyperinflation. 28 However, the role of bronchiectasis in COPD remains unclear.…”