Rationale: Muscle wasting in chronic obstructive pulmonary disease (COPD) is associated with a poor prognosis and is not readily assessed by measures of body mass index (BMI). BMI does not discriminate between relative proportions of adipose tissue and lean muscle and may be insensitive to early pathologic changes in body composition. Computed tomography (CT)-based assessments of the pectoralis muscles may provide insight into the clinical significance of skeletal muscles in smokers.Objectives: We hypothesized that objective assessment of the pectoralis muscle area on chest CT scans provides information that is clinically relevant and independent of BMI.Methods: Data from the ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) Study (n = 73) were used to assess the relationship between pectoralis muscle area and fat-free mass. We then used data in a subset (n = 966) of a larger cohort, the COPDGene (COPD Genetic Epidemiology) Study, to explore the relationship between pectoralis muscle area and COPD-related traits. Measurements and Main Results:We first investigated the correlation between pectoralis muscle area and fat-free mass, using data from a subset of participants in the ECLIPSE Study. We then further investigated pectoralis muscle area in COPDGene Study participants and found that higher pectoralis muscle area values were associated with greater height, male sex, and younger age. On subsequent clinical correlation, compared with BMI, pectoralis muscle area was more significantly associated with COPD-related traits, including spirometric measures, dyspnea, and 6-minute-walk distance (6MWD). For example, on average, each 10-cm 2 increase in pectoralis muscle area was associated with a 0.8-unit decrease in the BODE (Body mass index, Obstruction, Dyspnea, Exercise) index (95% confidence interval, -1.0 to -0.6; P , 0.001). Furthermore, statistically significant associations between pectoralis muscle area and COPD-related traits remained even after adjustment for BMI.Conclusions: CT-derived pectoralis muscle area provides relevant indices of COPD morbidity that may be more predictive of important COPD-related traits than BMI. However, the relationship with clinically relevant outcomes such as hospitalization and death requires additional investigation. Pectoralis muscle area is a convenient measure that can be collected in the clinical setting in addition to BMI.

Smoking-related chronic obstructive pulmonary disease is characterized by distal pruning of the small blood vessels (<5 mm(2)) and loss of tissue in excess of the vasculature. The magnitude of these changes predicts the clinical severity of disease.

OBJECTIVE-Coronary artery calcification (CAC) and thoracic aortic calcificatio (TAC) are frequently detected on ungated multi-detector computed tomography (MDCT) performed for lung evaluations. We sought to evaluate concordance of CAC and TAC scores on ungated (thoracic) and ECG-gated (cardiac) MDCT scans. METHODS-Fifty patients, enrolled in the GeneticEpidemiology of COPD study (COPDGene), were recruited to undergo gated CAC scans using 64-detector row CT, in addition to the ungated thoracic studies already being obtained as part of their study evaluation. Coronary and thoracic calcium was measured similarly (Agatston score, requiring 3 contiguous voxels of >130 Hounsfield units) using low-dose ungated studies and ECG-gated MDCT performed at the same scanning session. Intertechnique scoring variability and concordance were calculated. RESULTS-Correlationsbetween gated and ungated CAC and TAC were excellent (r = 0.96). The relative differences (median variability) measured by ECG-gated vs. ungated MDCT were relatively high for CAC (44%) but not for TAC (8%). Prevalence of depicted CAC (n=33, 66%) and TAC (n=21, 42%) were coincident between ECG-gated and ungated MDCT, respectively (inter-technique concordance 100%). Bland-Altman plots for CAC demonstrated mean differences of 354 (CI 169-538) and 16.1(CI −89-121).CONCLUSION-Low-dose ungated MDCT is reliable for prediction of the presence of CAC and assessment of Agatston score. Concordance between methods and between TAC and CAC is high. This technique should allow for atherosclerotic disease risk stratification among patients undergoing ungated lung CT evaluation without requiring additional scanning. Measurement of TAC is almost as accurate from gated CT, and CAC scores are highly concordant. Correspondence: Matthew Budoff, MD, 1124 West Carson Street, Building RB2, Torrance, CA 90502, Phone: (310) Fax: (310) 787-0448, mbudoff@labiomed.org. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Because CAC on CT distinctly identifies atherosclerosis2 , 3 , 4 , 5, it may be advantageous to screen for the CAD and lung cancer simultaneously in a combined CT examination to leader to broader diagnosis of these common and morbid diseases. CAC and thoracic aortic calcification (TAC) can be quantified on chest CT scans. New multi-detector computed tomography (MDCT) scanners, with faster gantry rotation times, thinner slices (detector row widths) and more detector rows now allow for estimates of CAC on ungated studies. The faster gantry rotation times reduce susceptibility to cardiac motion, and thinner detector row widths a...

OBJECTIVEDiabetes damages major organ systems through disrupted glycemic control and increased inflammation. The effects of diabetes on the lung have been of interest for decades, but the modest reduction in pulmonary function and its nonprogressive nature have limited its investigation. A recent systematic review found that diabetes was associated with reductions in forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and diffusing capacity for carbon monoxide of the lung and increased FEV1/FVC. They reported pooled results including few smokers. This study will examine measures of pulmonary function in participants with extensive smoking exposure.RESEARCH DESIGN AND METHODSWe examined pulmonary function in participants with a >10–pack-year history of smoking with and without diabetes with and without chronic obstructive pulmonary disease (COPD). We measured pulmonary function, exercise capacity, and pulmonary-related quality of life in 10,129 participants in the Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPDGene) Study.RESULTSParticipants with diabetes were observed to have reduced pulmonary function after controlling for known risk factors and also significant reductions in exercise capacity and quality of life across functional stages of COPD.CONCLUSIONSPulmonary function in patients with ≥10 pack-years of smoking and diabetes is reduced, and this decrease is associated with significant reductions in activity-related quality of life and exercise capacity.