TY - JOUR
T1 - Absence of positional change in pulmonary diffusing capacity in systemic sclerosis
AU - Ettinger, Walter H.
AU - Wise, Robert A.
AU - Stevens, Mary Betty
AU - Wigley, Fredrick M.
N1 - Funding Information:
From the Rheumatology and Respiratoty Medicine Divisions, Department of Medicine, Johns Hopkins School of Medicine, Good Samariin Hospital, and Baltimore City Hospitals, Baltimore, Maryland. This study was supported in part by an Arthritis Foundation Clinical Research Center Grant and the Johns Hopkins Multiputpose Arthriiis Center &ant 2-P60-AM2056S and Clinical Investigator Award-K06-HL00914 from the National Heart, Lung, and Blood Institute, the National Institutes of Health, Bethesda, Maryland. Requests for reprints should be addressed to Dr. Fredrick M. Wi-gley, Division of Rheumatology, Baltimore City Hospitals, 4940 Eastern Avenue, Baltimore, Maryland 21224. Manuscript accepted November 9, 1962.
PY - 1983/8
Y1 - 1983/8
N2 - Patients with systemic sclerosis frequently have pulmonary function abnormalities, and recent evidence suggests that pulmonary vascular involvement is a common manifestation. To test the hypothesis that patients with systemic sclerosis have impaired ability to recruit or distend the pulmonary vascular bed, the postural change in the coefficient of carbon monoxide diffusing capacity was measured in 11 patients with systemic sclerosis, and the results were compared with results from age-, smoking-, and sex-matched control subjects with rheumatoid arthritis and with results from healthy subjects. In normal subjects and patients with rheumatoid arthritis increased, the coefficient of diffusion by 9.4 percent (p < 0.005) and 8.4 percent (p < 0.01), respectively, when they moved from the sitting to the supine position. In contrast, patients with systemic sclerosis did not show a significant increase in coefficient of diffusion, even those who had otherwise normal pulmonary function. Regression analyses showed that the change in coefficient of diffusion decreased with increasing age (r = -0.57) in normal subjects, and that the change in coefficient of diffusion was a function of the percent predicted forced vital capacity, both in patients with systemic sclerosis (r = 0.59) and in those with rheumatoid arthritis (r = 0.70). Thus, these findings indicate that patients with systemic sclerosis have a nondistensible pulmonary capillary bed and that the absence of positional change in the coefficient of diffusion in systemic sclerosis is a subtle indicator of pulmonary involvement.
AB - Patients with systemic sclerosis frequently have pulmonary function abnormalities, and recent evidence suggests that pulmonary vascular involvement is a common manifestation. To test the hypothesis that patients with systemic sclerosis have impaired ability to recruit or distend the pulmonary vascular bed, the postural change in the coefficient of carbon monoxide diffusing capacity was measured in 11 patients with systemic sclerosis, and the results were compared with results from age-, smoking-, and sex-matched control subjects with rheumatoid arthritis and with results from healthy subjects. In normal subjects and patients with rheumatoid arthritis increased, the coefficient of diffusion by 9.4 percent (p < 0.005) and 8.4 percent (p < 0.01), respectively, when they moved from the sitting to the supine position. In contrast, patients with systemic sclerosis did not show a significant increase in coefficient of diffusion, even those who had otherwise normal pulmonary function. Regression analyses showed that the change in coefficient of diffusion decreased with increasing age (r = -0.57) in normal subjects, and that the change in coefficient of diffusion was a function of the percent predicted forced vital capacity, both in patients with systemic sclerosis (r = 0.59) and in those with rheumatoid arthritis (r = 0.70). Thus, these findings indicate that patients with systemic sclerosis have a nondistensible pulmonary capillary bed and that the absence of positional change in the coefficient of diffusion in systemic sclerosis is a subtle indicator of pulmonary involvement.
UR - http://www.scopus.com/inward/record.url?scp=0020513547&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0020513547&partnerID=8YFLogxK
U2 - 10.1016/0002-9343(83)91209-3
DO - 10.1016/0002-9343(83)91209-3
M3 - Article
C2 - 6881183
AN - SCOPUS:0020513547
VL - 75
SP - 305
EP - 312
JO - American Journal of Medicine
JF - American Journal of Medicine
SN - 0002-9343
IS - 2
ER -