Pulmonary hypertension in sickle cell disease

Background Recurrent vaso-occlusive episodes lead to progressive end-organ damage in patients with sickle cell disease. We sought to determine the prevalence of pulmonary hypertension in adult patients with sickle cell disease and to identify factors associated with this life-threatening complication. Methods Sixty patients (≥18 years of age; mean [± SD] age, 37 ± 13 years) followed at a University Medical Center were evaluated. They were selected by a systematic sampling of patients presenting to the clinic for routine follow-up visits. All enrolled subjects underwent a clinical examination, Doppler echocardiography, pulmonary function tests, and hematologic tests during a single visit. Pulmonary hypertension was defined using an age- and body mass index–adjusted nomogram. Results The prevalence of pulmonary hypertension was 30% (18/60). Ten patients had mild pulmonary hypertension (up to 44 mm Hg), 5 had moderate pulmonary hypertension (45 to 74 mm Hg), and 2 had severe pulmonary hypertension (≥75 mm Hg). In a logistic regression model, both lower fetal hemoglobin level and lower systolic blood pressure were associated with the presence of pulmonary hypertension. Conclusion We found that the prevalence of pulmonary hypertension in adult patients with sickle cell disease was substantial, particularly in those with lower levels of fetal hemoglobin and lower systolic blood pressure.