Prevalence of venous thromboembolism and its associations in a large racially homogenous population of sickle cell disease patients

To determine the prevalence of venous thromboembolism (VTE) among adult sickle cell disease (SCD) patients in Nigeria. Methods This was a multicentre retrospective study in which the medical records of adult SCD patients were reviewed. Information on demographics, steady-state haemogram, clinical phenotypes, duration of follow-up, history of VTE including risk factors and management was collected. Results Of the 509 SCD patients with a median (IQR) duration of follow-up of 2 years, 10 (2.0%) had VTE (9 DVT and 1 PE). Their median (IQR) age was 27 (22.8-30.3) years. Identifiable risk factors for VTE included positive family history (2, 20%) surgery, splenectomy, paraplegia and cancer (1, 10% each). No risk factor was identifiable in four persons. VTE had no significant association with age and gender. VTE was significantly associated with the following events: acute chest syndrome [p = .002, odds ratio (OR) 8, 95% CI 2.2-28.9], osteonecrosis [p = .012, OR 5.24, 95% CI, 1.45-18.91] and vaso-occlusive crisis [p = .035]. Also significantly associated with VTE were pulmonary hypertension [p = .001, OR 23.3, 95%CI 5.18-105.06] and stroke [p = .032, OR 9.35, 95%CI 0.87-53.25]. Conclusion The prevalence of VTE among SCD patients in Nigeria is low. It is significantly associated with vaso-occlusive crisis, pulmonary hypertension and stroke.