Dataset Information

Quantitative computed tomography phenotypes, spirometric parameters, and episodes of exacerbation in heavy smokers: An analysis from South America.

ABSTRACT:

Objective

To evaluate the quantitative computed tomography (QCT) phenotypes, airflow limitations, and exacerbation-like episodes in heavy smokers in Southern Brazil.

Methods

We enrolled 172 smokers with a smoking history ≥30 pack-years who underwent pulmonary function tests (PFTs) and CT scan for lung cancer screening. Patients were classified regarding airflow limitation (FEV1/FVC <0.7 forced expiratory volume in 1 second/forced vital capacity) and the presence of emphysema on the QCT. The QCT were analyzed in specialized software and patients were classified in two disease-predominant phenotypes: emphysema-predominant (EP) and non-emphysema-predominant (NEP). EP was determined as ≥6% of percent low-attenuation areas (LAA%) with less than -950 Hounsfield units. NEP was defined as having a total LAA% of less than 6%.

Results

Most of our patients were classified in the EP phenotype. The EP group had significantly worse predicted FEV1 (60.6 ±22.9 vs. 89.7 ±15.9, p <0.001), higher rates of airflow limitation (85.7% vs. 15%; p <0.001), and had more exacerbation-like episodes (25.8% vs. 8.3%, p <0.001) compared to the NEP group. Smoking history, ethnicity, and BMI did not differ between the groups. The total LAA% was the QCT parameter with the strongest correlation to FEV1 (r = -0.669) and FEV1/FVC (r = -0.787).

Conclusions

Heavy smokers with the EP phenotype on QCT were more likely to have airflow limitation, worse predicted FEV1, and a higher rate of exacerbation-like episodes than those with the NEP phenotype. Approximately 23% of patients with no airflow limitation on PFTs were classified in EP phenotype.

SUBMITTER: Barros MC

PROVIDER: S-EPMC6181358 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Quantitative computed tomography phenotypes, spirometric parameters, and episodes of exacerbation in heavy smokers: An analysis from South America.

Barros Marcelo Cardoso MC Hochhegger Bruno B Altmayer Stephan S Watte Guilherme G Zanon Matheus M Sartori Ana Paula AP Cavalet Blanco Daniela D Pacini Gabriel Sartori GS Chatkin Jose Miguel JM

PloS one 20181011 10

<h4>Objective</h4>To evaluate the quantitative computed tomography (QCT) phenotypes, airflow limitations, and exacerbation-like episodes in heavy smokers in Southern Brazil.<h4>Methods</h4>We enrolled 172 smokers with a smoking history ≥30 pack-years who underwent pulmonary function tests (PFTs) and CT scan for lung cancer screening. Patients were classified regarding airflow limitation (FEV1/FVC <0.7 forced expiratory volume in 1 second/forced vital capacity) and the presence of emphysema on th ...[more]

PMID: 30307987

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Dataset Information

Quantitative computed tomography phenotypes, spirometric parameters, and episodes of exacerbation in heavy smokers: An analysis from South America.

Objective

Methods

Results

Conclusions

Publications

Quantitative computed tomography phenotypes, spirometric parameters, and episodes of exacerbation in heavy smokers: An analysis from South America.

Similar Datasets

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