title: Prevalence and risk factors for pulmonary artery systolic hypertension among sickle cell disease patients in Nigeria.
abstract: Pulmonary artery systolic hypertension is common and associated with increased mortality among adult sickle cell disease (SCD) patients in the United States. Although the prevalence of SCD is highest in sub-Saharan Africa, the frequency of pulmonary artery systolic hypertension and the risk factors for the development of pulmonary hypertension have not been reported from Africa. We studied 208 hydroxyurea naïve Nigerian SCD patients at steady state and 94 healthy controls. Pulmonary artery systolic hypertension was defined prospectively as tricuspid regurgitant jet velocity > or =2.5 m/sec. Results were compared with a previously published US prospective SCD cohort. Only 7% of Nigerians compared with 46% of US adults with SCD were >35 years. Tricuspid regurgitant jet velocity was > or =2.5 m/sec in 25% of Nigerian SCD patients. Higher jet velocity was associated with greater serum globulin (P = 0.002), blood urea nitrogen (P = 0.019) and lactate dehydrogenase concentrations (P = 0.026) and with inability to walk >300 m in 6 min (P = 0.042). Compared with the US cohort, Nigerian patients had more hemolysis as indicated by lower hemoglobin and higher lactate dehydrogenase concentrations (P < or = 0.003). Pulmonary hypertension is common among Nigerian SCD patients. The public health implication of this finding is significant considering the potential number of individuals at risk for this complication. Better understanding of the long term outcome of pulmonary hypertension and causes of death in SCD and the institution of preventive measures are major public health challenges for Africa. The inclusion of African sites in sickle cell pulmonary hypertension clinical trials should be encouraged.
authors.affiliation: Department of Medicine and Center for Sickle Cell Disease, Howard University, Washington, District of Columbia 20060, USA. aliyuz@mail.nih.gov
authors.forename: Zakari Y
authors.initials: ZY
authors.lastname: Aliyu
authors.forename: Victor
authors.initials: V
authors.lastname: Gordeuk
authors.forename: Vandana
authors.initials: V
authors.lastname: Sachdev
authors.forename: Aliyu
authors.initials: A
authors.lastname: Babadoko
authors.forename: Aisha I
authors.initials: AI
authors.lastname: Mamman
authors.forename: Peter
authors.initials: P
authors.lastname: Akpanpe
authors.forename: Ester
authors.initials: E
authors.lastname: Attah
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Suleiman
authors.forename: Nurudeen
authors.initials: N
authors.lastname: Aliyu
authors.forename: Jamilu
authors.initials: J
authors.lastname: Yusuf
authors.forename: Laurel
authors.initials: L
authors.lastname: Mendelsohn
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Kato
authors.forename: Mark T
authors.initials: MT
authors.lastname: Gladwin
mesh_terms: D000293:Adolescent; D000328:Adult; D000755:Anemia, Sickle Cell / Q000150:complications* / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006918:Hydroxyurea; D006976:Hypertension, Pulmonary / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D009549:Nigeria / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D013599:Systole; D014262:Tricuspid Valve Insufficiency; D014481:United States
chemical_list: D006918:Hydroxyurea