Serial pulmonary function testing in patients with systemic lupus erythematosus.

Previous studies have documented the pulmonary function abnormalities associated with systemic lupus erythematosus (SLE). There are very few data, however, regarding the progression of such changes. To study this question, we evaluated the pulmonary function of a group of 25 patients with SLE from two to seven years after a set of pulmonary function tests had been performed as part of their overall initial assessment. Reductions in diffusing capacity, FVC, and total lung capacity did not change significantly for the group over the period of our study. The mean FEF25-75%, which was initially low, and the mean FEV1/FVC ratio, which was initially normal, both decreased significantly. The observed abnormalities in airway function were not related to smoking history. Other aspects of lupus activity, as measured by serum creatinine levels and clinical activity, did not appear related to progression of lung disease.