Clinical and functional assessment of patients with idiopathic pulmonary fibrosis: results of a 3 year follow-up.

The purpose of this study was to analyse the information provided by different techniques used in the assessment of patients with idiopathic pulmonary fibrosis (IPF) and their role in the prediction of lung function decline with the decline. Twenty seven subjects with IPF (55 +/- 14 (mean +/- SD) yrs) were studied at the initial staging. Nineteen of them (70%) were included in a follow-up over 3 yrs (32 +/- 6 months), whilst the remaining 8 patients were lost to follow-up. During the period of the study, 6 of the 19 patients died. A significant correlation between diffusing capacity of the lungs for carbon monoxide (DLCO) (and carbon monoxide transfer coefficient (KCO) = DLCO/alveolar volume (VA)) and the increase in alveolar-arterial oxygen tension difference (A-aPO2) during exercise (delta A-aPO2) was observed at diagnosis (r = -0.58). Despite the treatment with prednisone (1 mg.kg-1 daily during 4 weeks, tapered to an individualized maintenance daily dose of 15-30 mg), the 13 patients controlled throughout the whole period of the study showed a marked impairment in lung volumes; forced vital capacity (FVC) -0.46 +/- 0.09 l, from 69 +/- 16 to 52 +/- 11% of predicted, and total lung capacity (TLC) -0.39 +/- 0.11 l, from 75 +/- 16 to 62 +/- 14%, and in DLCO -0.6 +/- 0.2 mmol.min-1.kPa-1, from 56 +/- 15 to 47 +/- 18%, predicted. By contrast, both mean arterial oxygen tension (PaO2) and A-aPO2 at rest remained unchanged throughout the 3 yrs follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)