Blood Pressure Patterns and Factors Associated with Relative Hypertension among Steady State Sickle Cell Disease Patients in Kinshasa, Democratic Republic of the Congo: A Cross-Sectional Study

Abstract

Background: Although systemic hypertension is rarely seen in steady state sickle cell disease (SCD), relative hypertension has been reported to be associated with an increased risk of cardiovascular and renal complications. Objective: To determine the prevalence of BP patterns and assess factors associated with relative hypertension in sickle cell anemia (SCA) adult patients. Methods: Clinical data and office BP were obtained from 103 consecutive steady-state SCA adult patients (mean age 26 ± 7.9 years, 66% females, 22.3% on hydroxyurea) attending four healthcare centers providing SCD-specific care in Kinshasa. Seated BP was measured using an automated electronic device. Three consecutive blood pressure measurements were taken with 2 minutes interval between readings and the average of the 2 last readings was considered for the analyses. Normal BP, relative hypertension and systemic hypertension were defined as BP < 120/70 mmHg, 120 -139/70 -89 mmHg and ≥140/90 mmHg, respectively. Results: Normal BP, relative hypertension and systemic hypertension were observed in 56 (54%), 43 (42%) and 4 (4%) of SCA patients, respectively. In multivariate analysis, factors associated with relative hypertension were leg ulcer (aOR 2.05; 95%CI 1.77 -5.18; p = 0.016), central obesity (aOR 3.32; 95%CI 1.28 -6.24; p = 0.001), smoking (aOR 5.02; 95%CI 1.51 -9.50; p = 0.017), and microalbumiuria (aOR 3.44; 95%CI 1.44 -5.76; p = 0.035). Conclusion: Relative hypertension was a common finding in the present case series and associated with traditional cardiovascular risk factor as well as factors specific to SCD highlighting the need for measures to prevent its progression towards systemic hypertension and associated cardiovascular and renal disease.