PULMONARY-FUNCTION TESTS AND CT SCAN IN THE MANAGEMENT OF IDIOPATHIC PULMONARY FIBROSIS

Relationships between pulmonary function testing and high-resolution c omputed tomography (HRCT) were studied in 39 untreated patients with i diopathic pulmonary fibrosis (IPF) at diagnosis, 23 of whom were follo wed during 7.5 +/- 0.3 mo (mean +/- SEM). At diagnosis, the extent of overall lung involvement in the HRCT scans showed a moderate but signi ficant correlation only with FVC (r = -0.46, p = 0.003) and DLCO (r = -0.40, p = 0.03). The extent of ground glass pattern also correlated w ith FVC (r = -0.58, p = 0.0001). Arterial P-O2 at peak exercise (n = 1 3 patients) showed a significant association with the extent of both g round-glass pattern and overall long involvement in HRCT (r = -0.60, p = 0.02; and r = -0.64, p = 0.01, respectively). On multivariate analy sis a significant independent correlation between the global disease e xtent in HRCT and both FVC and DLCO, was observed. Changes over time i n the total extent of the disease evaluated with HRCT scans were also related to those observed in DLCO and in FVC (r = -0.57, p = 0.01, and r = -0.51, p = 0.01, respectively). The present study suggests that F VC and DLCO are the physiological variables that best reflect the glob al extent of disease in IPF and thus may provide significant informati on for the assessment of the disease's progression.