Abnormal Pulmonary Function in Adults and Children with Sickle Cell Disease.

Abstract

Introduction: Chronic lung disease is a fatal complication in sickle cell disease (SCD) often undiagnosed until late stages. Early detection and treatment of risk factors may improve survival. Since asthma, pulmonary hypertension (PHT), and acute chest syndrome (ACS) are potential risk factors, in 1998, we began screening patients with history of ACS or wheezing with pulmonary function tests (PFT) and echocardiogram (echo).Methods: A chart review was completed on the 362 adults and children evaluating history of asthma, lung function (PFT) and PHT (echo, tricuspid regurgitant jet velocity ≥ 2.5).Results:PFT FindingsAll AgesAdultsChildrenPHT (All Ages)Study performed34% (124/362)41% (95/232)22% (29/130)Echo: 90% (111/124)Abnormal85% (106/124)87% (83/95)79% (23/29)51% (54/106)Obstructive (OBS) only31% (33/106)31% (26/83)30% (7/23)42% (14/33)Restrictive (REST) only30% (32/106)28% (23/83)39%(9/23)38% (12/32)Both OBS + REST pattern27% (29/106)29% (24/83)22% (5/23)69% (20/29)“Abnormal,” not specified11% (12/106)12% (10/83)9% (2/23)67% (8/12)DLCO < 65% predicted48% (45/94)53% (42/80)21% (3/14)54% (26/48)Diagnosis & TreatmentClinical asthma diagnosis13% (47/362)14% (33/232)11% (14/130)43% (20/47)Receiving asthma treatment51% (24/47)45% (15/33)64% (9/14)50% (12/24)Bronchodilator only23% (11/47)24% (8/33)21% (3/14)45% (5/11)Inhaled steroid23% (11/47)18% (6/33)36% (5/14)55% (6/11)Singulair4% (2/47)3% (1/33)7% (1/14)50% (1/2)PFT suggests asthma50% (62/124)53% (50/95)41% (12/29)53% (33/62)+PFT, + asthma treatment16% (10/62)14% (7/50)25% (3/12)80% (8/10)One hundred twenty-four patients underwent PFTs, of which 111 (85%) were abnormal. Obstructive and/or restrictive disease with abnormal diffusion capacity were widespread. Of patients with an obstructive pattern, only 16% were receiving any asthma treatment. Forty-seven patients (33 adults and 14 children) were diagnosed with asthma. However, only half were receiving any treatment: 23% bronchodilators, and 23% inhaled steroids. Echo was performed on 90% of patients with PFT data. Half of all patients with abnormal PFTs, and 69% of those with obstructive/restrictive patterns, had PHT.Conclusion: While a more severe population may have been tested, this data suggests abnormal lung function is prevalent in SCD and is associated with PHT. Recent data suggests abnormal NO metabolism may link asthma and PHT in SCD. In conclusion, our data suggests patient morbidity will be decreased by regular screening with PFT and echo followed by early treatment for asthma and PHT.