Decades after the cooperative study: a re-examination of systemic blood pressure in sickle cell disease.

Previous studies report lower systemic blood pressures in patients with sickle cell disease (SCD) than in appropriate controls. The etiology of the lower systolic and diastolic blood pressures (SBP and DBP) remains uncertain. Blood pressure measurements from patients followed at our center (UNC cohort) were compared with values obtained from the Cooperative Study of Sickle Cell Disease (CSSCD) and healthy control subjects. Associations of SBP and DBP with clinical and laboratory covariates were performed in the UNC cohort. Patients in the UNC cohort were significantly older and had a higher BMI than those in the CSSCD (p <0.0001). There were no differences in the SBP and DBP between SCD patients in the UNC cohort and control subjects. In the SS/SD/Sβ(0) thalassemia group, SBP was higher in the UNC cohort than in the CSSCD (p < 0.0001). On multivariate analysis, significant correlations were noted between SBP and age, BMI, history of hypertension and absolute neutrophil count. Compared with historic controls, SBP was significantly higher in our SCD patient cohort. There was no difference when blood pressure was compared between our patient cohort and control subjects. Age, BMI and neutrophil count may contribute to the modulation of SBP in SCD.