Skeletal muscle, subcutaneous fat, and clinical outcomes in smokers.

Raul San Jose Estepar

Raúl San José Estépar, PhD

Co-Director, Applied Chest Imaging Laboratory
Lead Investigator, Brigham and Women's Hospital
Associate Professor of Radiology, Harvard Medical School
Raúl is co-director of the Applied Chest Imaging Laboratory, lead scientist at Brigham and Women's Hospital and Associate Professor of Radiology at Harvard Medical School. 
1249 Boylston St, Room 216
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Diaz AA, Zhou L, Young TP, McDonald M-L, Harmouche R, Ross JC, Estepar RSJ, Wouters EFM, Coxson HO, MacNee W, Rennard S, Maltais F, Kinney GL, Hokanson JE, Washko GR. Chest CT measures of muscle and adipose tissue in COPD: gender-based differences in content and in relationships with blood biomarkers. Acad Radiol 2014;21(10):1255-61.Abstract
RATIONALE AND OBJECTIVES: Computed tomography (CT) of the chest can be used to assess pectoralis muscle area (PMA) and subcutaneous adipose tissue (SAT) area. Adipose tissue content is associated with inflammatory mediators in chronic obstructive pulmonary disease (COPD) subjects. Based on gender differences in body composition, we aimed to assess the hypothesis that in subjects with COPD, the relationships between PMA, SAT, and blood biomarkers of inflammation differ by gender. MATERIALS AND METHODS: We compared chest CT measures of PMA and SAT on a single slice at aortic arch and supraesternal notch levels from 73 subjects (28 women) with COPD between genders. The relationships of PMA and SAT area to biomarkers were assessed using within-gender regression models. RESULTS: Women had a lesser PMA and a greater SAT area than men (difference range for PMA, 13.3-22.8 cm²; for SAT, 11.8-12.4 cm²; P < .05 for all comparisons) at both anatomic levels. These differences in PMA and SAT remained significant after adjustment for age and body mass index. Within-gender regression models adjusted for age showed that SAT was directly associated with C-reactive protein (for aortic arch level, P = .04) and fibrinogen (for both anatomic locations, P = .003) only in women, whereas PMA was not associated with any biomarkers in either gender. CONCLUSIONS: It appears that in subjects with COPD, there are gender-based differences in the relationships between subcutaneous adipose tissue and inflammatory biomarkers.