Abstract Archives of the RSNA, 2003
Q02-1216
The Measurement of Lung Structural Changes due to Anorexia Nervosa Using Computed Tomography
Scientific Papers
Presented on December 4, 2003
Presented as part of Q02: Chest (High-Resolution CT)
Ida Chan, PRESENTER: Nothing to Disclose
Abstract:
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Purpose: We hypothesized that long-term protein-calorie malnutrition in
humans results in emphysematous changes in the lung parenchyma.
Methods and Materials: CT scans were obtained from 14 subjects with a DSM IV
diagnosis of anorexia nervosa (AN). All patients gave their informed consent to
take part in this study. Clinical data: sex, age, smoking history, body mass
index (BMI), total body fat, hemoglobin (HGB), history of age of onset of AN
and duration of malnutrition, and history of respiratory disease were recorded.
Pulmonary function data (static and dynamic lung volumes, diffusing capacity
and respiratory muscle strength) were measured. CT scans were obtained from
three regions of the lung (at the level of the aortic arch, the carina, and the
posterior position of the 8th rib) using a Multi-Slice CT scanner
(GE Lightspeed Ultra). Images were reconstructed using 1.25, 2.5 and 5 mm CT
slice thickness. The mean lung density (g/ml), lung inflation (ml gas/g tissue),
and surface area to volume ratio (S/V) were measured using the x-ray
attenuation values of the CT images. The CT measures were correlated with the
anthropometric and the pulmonary function data measurements and compared to the
same data in 16 control subjects.
Results: These data show the AN subjects were not anemic (HGB=12.6±0.9 g/dL) and there were no significant
differences in age or pulmonary function between AN and control subjects. There
was a significant difference in the mean lung density (0.18±0.04 g/ml vs 0.23±0.03 g/ml, p=0.001), mean lung inflation (5.0±1.5 ml/g vs 3.7±0.7 ml/g, p=0.006) and S/V (13.6±7.0
m2/ml vs 25.1±6.9 m2/ml,
p=0.0001) between AN and control subjects. Simple regression analysis showed
there was no significant correlation between FEV1, FVC, TLC and maximum
expiratory pressure and CT measurements. However, there was a significant
correlation between the percent predicted diffusing capacity of the lung for
carbon monoxide (DLCO%p, corrected for hemoglobin) and mean lung density
(r=0.75) mean lung inflation (r=0.81), S/V (r=0.67) and BMI (r=0.70) (pŁ0.05) in the AN subjects. A step-wise
multiple regression showed the best predictor of DLCO%p was mean lung
inflation, S/V and the percentage of lung less 6 ml/g of air (R2=0.86,
p=0.01).
Conclusion: There is a significant correlation between the diffusing capacity
of the lung and CT measurements of lung structure and body mass index in
patients with AN. These data suggest that there are "emphysema-like"
changes (density, inflation, S/V) in the underlying structure of the lung in
malnourished patients. (J.M. received a grant from GE Medical Systems, Canada.)
Questions about this event email: hcoxson@vanhosp.bc.ca
Chan, I,
The Measurement of Lung Structural Changes due to Anorexia Nervosa Using Computed Tomography. Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL.
http://archive.rsna.org/2003/3101071.html