Thus, we believe that in choosing the MEF25 reduction for the detection of SAD, we have achieved an adequate reliability, even though dynamic compliance and CV were not measured, while we did not consider including invasive methods such as open or transbronchial biopsies.
Alton and Turner-Warwick have noted that the existence of lung involvement in scleroderma is difficult to establish, because lung disease may remain “silent,” depending on the method used for its identification. Summarizing the results of 19 pertinent studies, a mean prevalence of pulmonary involvement of 81 percent among 512 patients with scleroderma (range, 53 to 100 percent) was noted.
The relatively low prevalence of 61 percent of pulmonary involvement that we found in the present study may be attributed to the fact that all our patients were lifelong nonsmokers. This is in agreement with the findings of some others. Steen et al found 66 percent prevalence among a group of 165 studied nonsmoking patients with scleroderma. Moreover, they found that smoking patients had much lower Deo compared with nonsmokers and suggested that an additive deleterious effect of smoking is associated with increased severity of restrictive disease in systemic sclerosis.