Abnormal pulmonary function in adults with sickle cell anemia.
BACKGROUND
Pulmonary complications of sickle cell anemia (Hb-SS) commonly cause morbidity, yet few large studies of pulmonary function tests (PFTs) in this population have been reported.


OBJECTIVE
PFTs (spirometry, lung volumes, and diffusion capacity for carbon monoxide [DLCO]) from 310 adults with Hb-SS were analyzed to determine the pattern of pulmonary dysfunction and their association with other systemic complications of sickle cell disease.


METHODS
Raw PFT data were compared with predicted values. Each subject was subclassified into one of five groups: obstructive physiology, restrictive physiology, mixed obstructive/restrictive physiology, isolated low DLCO, or normal. The association between laboratory data of patients with decreased DLCO or restrictive physiology and those of normal subjects was assessed by multivariate linear regression.


RESULTS
Normal PFTs were present in only 31 of 310 (10%) patients. Overall, adults with Hb-SS were characterized by decreased total lung capacities (70.2 +/- 14.7% predicted) and DLCO (64.5 +/- 19.9%). The most common PFT patterns were restrictive physiology (74%) and isolated low DLCO (13%). Decreased DLCO was associated with thrombocytosis (p = 0.05), with hepatic dysfunction (elevated alanine aminotransferase; p = 0.07), and a trend toward renal dysfunction (elevated blood urea nitrogen and creatinine; p = 0.05 and 0.07, respectively).


CONCLUSIONS
Pulmonary function is abnormal in 90% of adult patients with Hb-SS. Common abnormalities include restrictive physiology and decreased DLCO. Decreased DLCO may indicate more severe sickle vasculopathy characterized by impaired hepatic and renal function.
Pulmonary Center, Department of Medicine, Boston Comprehensive Sickle Cell Center, Boston University School of Medicine and School of Public Health, Boston, MA 02118, USA. eklings@lung.bumc.bu.edu
Elizabeth S
ES
Klings
Diego F
DF
Wyszynski
Vikki G
VG
Nolan
Martin H
MH
Steinberg
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000755:Anemia, Sickle Cell / Q000150:complications / Q000503:physiopathology*; D002248:Carbon Monoxide / Q000378:metabolism; D005260:Female; D006801:Humans; D016015:Logistic Models; D008171:Lung Diseases / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011653:Pulmonary Diffusing Capacity; D012129:Respiratory Function Tests; D012143:Respiratory Physiological Phenomena
D002248:Carbon Monoxide