Study objectives: To evaluate exercise testing for the
assessment of the extent of pulmonary disease in patients with
Design: Retrospective analysis of
consecutive patients with sarcoidosis referred to the Pulmonary
Physiology Laboratory between 1992 and 1997, who completed at least 6
min of progressive bicycle exercise. Resting and exercise pulmonary
function measurements were compared to radiographic stage of
Setting: Pulmonary Physiology Laboratory at
Washington, DC, Veterans Affairs Medical Center.
Patients: Forty-eight outpatient veterans with biopsy
Results: Across all
radiographic stages of sarcoidosis, total lung capacity, resting
diffusing capacity, and exercise gas exchange measurements had a
significant variance with radiographic stage. Across the early
radiographic stage disease (stages 0 to 2), the change in
alveolar-arterial oxygen pressure gradient between rest and exercise,
normalized for oxygen uptake, was the most significant measurement in
its variation with radiographic stage.
Changes in gas exchange with exercise may be the most sensitive
physiologic measurements to assess the extent of disease in early
radiographic stages of sarcoidosis.