Prevalence of cardiovascular disease and thromboembolic events in a prospective cohort of patients with sickle cell disease

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Sickle cell disease (SCD) is an inherited disorder of globin chains that cause haemolysis, thrombosis and chronic organ damage. SCD affects multiple organs including the cardiovascular system. The two main subtypes of SCD are the homozygous HbSS and the heterozygous HbSC form. Here we describe and compare the prevalence of cardiovascular disease and thromboembolic events between HbSS and HbSC forms of SCD. Methods This is an observational study where a prospective database of SCD patients from a UK centre was retrospectively analysed. Results A total of 291 patients were included from the database with 183 (63%) HbSS patients. HbSS patients were younger (40.8±11 vs 48.1±14, p=0.03) with more males (49% v 35%, p=0.02) compared to the HbSC group. As expected, HbSS patients had more severe form of the disease with higher rate of hospital admissions for sickle related crises, transfusion related iron overload, and are more likely to be on prophylactic phenoxymethylpenicillin as well as disease modifying treatments (Table 1). Cardiovascular risk factors hypertension and hypercholesterolemia were less prevalent in HbSS compared to HbSC patients. Interestingly, the prevalence of ischaemic heart disease and vascular disease is similarly low in both groups at around 1%. However, the prevalence of thromboembolic events, pulmonary hypertension and stroke/TIA is higher at between 4 to 8% with no significant difference between the groups (Table 2). Conclusion The different prevalence of cardiovascular risk factors between HbSS and HbSC may be explained by the difference in age between the groups. SCD would appear to have a differential effect on the cerebral, cardiac, pulmonary and peripheral circulations.