Estimated pulmonary artery systolic pressure and sickle cell disease: a meta-analysis and systematic review

Many studies report estimated pulmonary artery systolic pressure (ePASP) in patients with sickle cell disease (SCD) screened by echocardiography. To better understand the prevalence and outcomes of elevated ePASP in clinically stable SCD patients, we conducted a random-effects meta-analysis. A total of 45 studies, representing 15 countries and including 6109 individuals, met our inclusion criteria. In most (70%) studies, elevated ePASP was defined by a tricuspid regurgitant velocity of 2.5 m/s. The prevalence of elevated ePASP was 21% (17-26%) in children and 30% (26-35%) in adults. After adjustment for sex, SCD genotype, haemoglobin, hydroxycarbamide (hydroxyurea) treatment, country and publication year, age remained associated with elevated ePASP, yielding a 12% (0.4-23%) higher adjusted prevalence in adults. Few studies reported 6-min walk tests or mortality outcomes, and estimates were highly heterogeneous. In random effects meta-analyses, patients with elevated ePASP walked an estimated 30.4 (6.9-53.9) metres less than those without elevated ePASP and had an associated mortality hazard ratio of 4.9 (2.4-9.7).