Restricted Pulmonary Function in Cystic Fibrosis: Serial Studies

Serial Studies
Seventeen of the 20 patients (including seven matched pairs) had pulmonary function tests repeated during their 1985-86 annual examination, one year after the initial study. One restricted patient died prior to repeat assessment. Two nonrestricted patients did not have repeat tests (one due to an exacerbation of disease and one was lost to follow-up). Results of repeat pulmonary function tests in seven matched pairs showed a trend toward improvement in the restricted patients but not in the control subjects. The TLC increased 0.52 L (4.75 to 5.22 L) in the restricted and decreased 0.09 L (5.88 to 5.79 L) in the nonrestricted patients (p = 0.08 for time, p = 0.12 for group, and p = 0.02 for interactive effects). The VC increased an average of 0.45 L (2.63 to 3.08 L) in the restricted and decreased 0.19 L (2.62 to 2.43 L) in the nonrestricted patients (not significant for time and group effects; p = 0.04 for interactive effect). Indices of expiratory flow demonstrated a trend of improvement in the restricted patients and a decline in control subjects, but these changes were not statistically significant.

There were marked changes in pulmonary volume over one year in individual patients. Three of the nine restricted patients with repeat tests were no longer restricted one year later (increases in TLC[P] of 0.80, 0.83, and 1.09 L). None of the nonrestricted patients became restricted one year later. Because of the improvement in pulmonary volumes for restricted patients one year later (1985-86), we also examined pulmonary volumes of 16 patients with available pulmonary function tests in 1983-84, one year earlier. Two of eight restricted patients were not restricted in 1983-84 (one of whom was also not restricted two years later in 1985-86), and two of eight nonrestricted patients were restricted one year earlier in 1983-84. These changes in serial pulmonary volume were not associated with any consistent changes in blind ratings (EJ.F.) of serial chest roentgenograms over the same period.

Category: Pulmonary Function

Tags: airway, cystic fibrosis, Pulmonary Function