References: Dodd et al, 2006
Radiology. 2006 Jul;240(1):236-45.
Thin-section CT in patients with cystic fibrosis: correlation with peak
exercise capacity and body mass index.
Dodd JD, Barry SC, Barry RB, Gallagher CG, Skehan SJ, Masterson JB.
Department of Radiology, St Vincent's University Hospital, Dublin, Ireland.
Abstract
PURPOSE: To evaluate whether thin-section chest computed tomographic (CT)
findings correlate with exercise capacity, body mass index (BMI), dyspnea,
and leg discomfort in patients with cystic fibrosis (CF).
MATERIALS AND METHODS: Institutional ethics committee approval was obtained,
and patients provided written informed consent. Twenty-two patients (13 male
and nine female patients; mean age, 22 years +/- 5.9; age range, 17-41
years) with stable CF underwent thin-section CT and exercise testing on a
cycle ergometer. Three radiologists blinded to the clinical severity of
disease and the spirometric findings of all patients independently and
randomly scored all scans with a modified Bhalla scoring system. The primary
measurement of the outcome of exercise testing was percentage of predicted
peak O2 uptake. Univariate (Spearman rank correlation) and multivariate
analyses were used to compare thin-section CT, clinical (age, sex,
spirometric data, and BMI), and exercise measurements.
RESULTS: The correlation between total thin-section CT score and percentage
of predicted peak O2 uptake was stronger than the correlation between the
percentage of predicted peak O2 uptake and any clinical measurement (R =
-0.60, P < .01). The thin-section CT structural abnormalities that had the
strongest correlation with percentage of predicted peak O2 uptake were
severity of bronchiectasis and presence of sacculations or abscesses (R =
-0.70 and -0.71, respectively; P < .01). Multivariate analysis showed total
thin-section CT score to be the only significant predictor of exercise
capacity, accounting for 42% of the variance in percentage of predicted peak
O2 uptake.
CONCLUSION: In patients with CF, the correlation between thin-section CT
score and exercise limitation is stronger than that between spirometry
results or BMI and exercise limitation.