Dataset Information

Objectively Measured Chronic Lung Injury on Chest CT.

ABSTRACT:

Background

Tobacco smoke exposure is associated with emphysema and pulmonary fibrosis, both of which are irreversible. We have developed a new objective CT analysis tool that combines densitometry with machine learning to detect high attenuation changes in visually normal appearing lung (Norm_HA) that may precede these diseases.

Methods

We trained the classification tool by placing 34,528 training points in chest CT scans from 297 COPDGene participants. The tool was then used to classify lung tissue in 9,038 participants as normal, emphysema, fibrotic/interstitial, or Norm_HA. Associations between the quartile of Norm_HA and plasma-based biomarkers, clinical severity, and mortality were evaluated using Jonckheere-Terpstra, pairwise Wilcoxon rank-sum tests, and multivariable linear and Cox regression.

Results

A higher percentage of lung occupied by Norm_HA was associated with higher C-reactive protein and intercellular adhesion molecule 1 (P for trend for both < .001). In analyses adjusted for multiple covariates, including high and low attenuation area, compared with those in the lowest quartile of Norm_HA, those in the highest quartile had a 6.50 absolute percent lower percent predicted lower FEV₁ (P < .001), an 8.48 absolute percent lower percent predicted forced expiratory volume, a 10.78-meter shorter 6-min walk distance (P = .011), and a 56% higher risk of death (P = .003). These findings were present even in those individuals without visually defined interstitial lung abnormalities.

Conclusions

A new class of Norm_HA on CT may represent a unique tissue class associated with adverse outcomes, independent of emphysema and fibrosis.

SUBMITTER: Harmouche R

PROVIDER: S-EPMC6904856 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Publications

Dietary carbohydrate restriction in type 2 diabetes mellitus and metabolic syndrome: time for a critical appraisal.

Accurso Anthony A Bernstein Richard K RK Dahlqvist Annika A Draznin Boris B Feinman Richard D RD Fine Eugene J EJ Gleed Amy A Jacobs David B DB Larson Gabriel G Lustig Robert H RH Manninen Anssi H AH McFarlane Samy I SI Morrison Katharine K Nielsen Jørgen Vesti JV Ravnskov Uffe U Roth Karl S KS Silvestre Ricardo R Sowers James R JR Sundberg Ralf R Volek Jeff S JS Westman Eric C EC Wood Richard J RJ Wortman Jay J Vernon Mary C MC

Nutrition & metabolism 20080408

Current nutritional approaches to metabolic syndrome and type 2 diabetes generally rely on reductions in dietary fat. The success of such approaches has been limited and therapy more generally relies on pharmacology. The argument is made that a re-evaluation of the role of carbohydrate restriction, the historical and intuitive approach to the problem, may provide an alternative and possibly superior dietary strategy. The rationale is that carbohydrate restriction improves glycemic control and re ...[more]

PMID: 18397522

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