Objective: To examine pulmonary function, dyspnea and exercise capacity in adult Saudi sickle cell disease (SCD) patients.
Methods: The patients were recruited from the hematology clinic at King Khalid University Hospital in Riyadh from January to December 2005. The study involved 39 patients with stable SCD (20 women and 19 men), with a mean age of 22.7+/-7.1 years, hemoglobin level of 95.5+/-14.6 g/L and hemoglobin F level of 13.7+/-8.6%. Patients underwent pulmonary function tests (PFT) (forced expiratory volume in first second [FEV1], forced vital capacity [FVC], and diffusion capacity of carbon monoxide [DLco] data are presented as a percentage of the normal prediction), a 6-minute walk test (6MWT) and echocardiography. Dyspnea was assessed using the Borg score. The 6MWT data were compared to body mass index-matched healthy controls.
Results: Forty-one percent of SCD patients had mild dyspnea at rest, and this increased to 61% at the end of the 6MWT. Pulmonary function tests were abnormal in 51% (36% of patients had a restrictive pattern, 10% had isolated decrease in DLco, and 5% had a mixed restrictive-obstructive pattern). The 6MWD was shorter in SCD patients compared to the controls (368+/-67 versus 407+/-47m, p=0.005). No hematological variables correlated with outcome variables.
Conclusion: Chronic pulmonary complications in adult Saudi SCD patients are relatively mild but common. Pulmonary function in these patients differs from that published for African-origin SCD patients. This difference may reflect a different natural history of SCD in the 2 populations.