Abstracts

Rationale: While significant improvements in quality of life and survival have occurred for Jamaican patients with SCD, patients continue to experience major neurological complications, including seizures. Although epilepsy is known to be more common in patients with SCD, little is known of the incidence of epilepsy in these patients and how its occurrence affects survival. Methods: Records of patients with all sickle genotypes in the Jamaica Sickle Cell Cohort followed from birth were retrospectively reviewed to identify those with seizures and to determine whether events were febrile convulsions (FC), acute symptomatic seizures (AcS), single unprovoked seizures (SiS) or recurrent unprovoked seizures i.e. epilepsy. For this study, FC was defined as an acute febrile illness occurring in the absence of severe sickle-related complications of septicemia or severe respiratory events. A seizure with fever and these conditions was classified as AcS. Additional data included imaging, EEG, treatment and outcomes. Data were analyzed on Stata 9.2 Results: There were 206 documented seizures, mainly generalized tonic-clonic(GTC) with 2 atonic and 3 partial seizures. Overall there were 38 patients affected (1-133 seizures/person, F: M = 1: 1.7) during the follow-up period of June 1973 to February 2007. At first presentation, FC and AcS accounted for 39.5% each (15/38); the remaining 21% were single unprovoked seizures. The incidence of FC was 447/100,000 person-years with a cumulative incidence of 2.58% and 805/100,000 person-years in patients with HbSS genotype. The probability of death by age 7 years was higher in SCD patients with FC compared to those without (p< 0.02). When FC were excluded, those persons initially presenting with AcS or SiS were, combined, almost three times more likely to have died (HR 2.8). The risk of developing epilepsy was greatest if the presenting seizure was an AcS (relative risk 2.8) The incidence of epilepsy in this cohort, composed of all major genotypes of sickle cell disease, was 96.9/100,000 and 182.8/100,000 person-years in the most severe genotype (HbSS). In this study, males were 4 times more likely to develop epilepsy than females.