To review and evaluate:

1) The association of sickle cell genotypes and phenotype with emphasis on neurological complications

2) The risk factors for ischemic stroke in adult with Sickle Cell Disease (SCD)

3) The correlation between cerebrovascular disease and cognitive morbidity

4) The impact of transfusion and hydroxyurea on the stroke incidence in adults with SCD.

Risk factors for neurological complications in sickle cell disease (SCD) differ in the Adult and Paediatric population. Here, we focus on neurological complications in adults with SCD.

A total of 303 patients were enrolled: HbSS genotype 56%, HbSC genotype 35%, HbSβ thalassemia genotype 56%; the mean age 38.8yrs (± 13.5 SD) with 46% males. The most common neurological complication was cerebrovascular disease (n=37; 12%) including those with ischaemic stroke (10%), cerebral vasculopathy (3%) and intracranial haemorrhage (1%). Ischaemic stroke was common among the HbSS genotype compared to other genotypes (8% vs 1.6%, p=0.001). Comparing SCD patients who had suffered stroke to those who had not, there was a higher proportion of intracranial vasculopathy (p=0.001, in particular Moyamoya) or cognitive dysfunction (p<0.0001). Compared to hydroxyurea and/or carbamide or no therapy, relative risk reduction of ischaemic stroke with transfusion was 2.78 (95% Cl 1.32 to 5.89), p=0.005.