REVIEW ARTICLE The global burden of pulmonary hypertension in sickle cell disease: a systematic review and meta-analysis B. M. Musa 1 & N. A. Galadanci 2 & M. Coker 3 & S. Bussell 4,5 & M. H. Aliyu 4,5,6 Received: 7 March 2016 /Accepted: 9 May 2016 # Springer-Verlag Berlin Heidelberg 2016 Abstract Elevated tricuspid regurgitant jet velocity (TRJV) is a surrogate measure of pulmonary hypertension (PH) in persons with sickle cell disease (SCD). We sought to estimate the burden of PH in people living with sickle cell disease based on TRJV. From 2000 to 2015, we searched electronic databases for eligible publications and included 29 studies (n =5358 persons). We used random effects modeling to de- termine the pooled estimate of elevated TRJV. The overall pooled prevalence of elevated TRJV was 23.5 %(95 % CI 19.5–27.4) in persons with SCD. The pooled prevalence of elevated TRJV in children and adults with SCD was 20.7 % (95 % CI 15.7–-25.6) and 24.4 % (95 % CI 18.4–30.4), re- spectively. TRJV is prevalent among adults and children with SCD. Our finding support international recommendations that call for screening for PH in SCD patients. Keywords Africa . Pulmonary hypertension . Tricuspid velocity . Sickle cell disease . Meta-analysis Introduction Sickle cell disease (SCD) is an inherited genetic blood disorder characterized by sickling of red blood cells with accompanying end organ damage from hemolytic anemia and vaso-occlusion [1]. The WHO estimates that about 300,000 children are born with SCD each year, predominately in Africa and among peo- ple of African descent [2]. In 1936, Yater and Hansmann first described the association between pulmonary hypertension (PH) and SCD [3]. Studies find that PH occurs frequently in children and adults with SCD [4, 5]. Explanations for PH in SCD patients include reaction to hemolysis and altered nitric acid metabolism [6–8]. Furthermore, PH is associated with morbidity and mortality in SCD [9]. Right ventricular catheterization is the gold standard for determining PH. A normal end systolic pressure is 15 mmHg, a value ≥25 mmHg is regarded as elevated [10, 11]. A non-invasive method for screening adults with SCD to determine the presences of pulmonary hypertension uses Doppler echocardiography (ECHO) to measure tricuspid regurgitant velocity (TRV). Tricuspid valve regurgitant jet ve- locity (TRJV) of ≥2.5 m/s in SCD is associated with increased mortality [12–14]. Gladwin et al. demonstrated a fourfold higher risk of death among persons with SCD who have TRJV between 2.5 and 2.9 m/s compared to those with normal TRJV [12]. Gladwin’ s work set a TRJV value of ≥2.5 m/ s mmHg in persons with SCD as the cutoff for PH. This TRJV value also corresponds to a pulmonary arterial pressure of ≥25 mmHg [12]. PH is found in about 10 % of patients with elevated TRJV [15]. Thus, experts agree that an elevated TRJV of ≥2.5 m/s is a surrogate marker for PH [12–14]. Several studies have attempted to determine the prevalence of elevated TRJV in children, adults, and pregnant women with SCD [16–22]. Nevertheless, approximations of PH in SCD patients vary widely, thus supporting our meta-analysis * B. M. Musa babamaiyaki2000@yahoo.co.uk 1 Department of Medicine, Bayero University/Aminu Kano Teaching Hospital, Kano, Nigeria 2 Department of Hematology, Bayero University/Aminu Kano Teaching Hospital, Kano, Nigeria 3 Institute of Human Virology, University of Maryland, Baltimore, USA 4 Vanderbilt Institute for Global Health, Vanderbilt University School of Medicine, Nashville, TN, USA 5 Department of Preventive Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA 6 Departments of Family and Community Medicine, Meharry Medical College, Nashville, USA Ann Hematol DOI 10.1007/s00277-016-2693-z