Seizures in the Jamaica cohort study of sickle cell disease

Abstract

Although there is some evidence that epilepsy is more common in Sickle Cell Disease (SCD), we sought to establish the incidence rates, risk factors for and specific types of seizures in a SCD cohort followed from birth, and how seizure occurrence affects morbidity and mortality. We examined all records of persons in the Jamaica cohort Study of Sickle Cell Disease (JSSCD) clinically identified as having experienced a seizure during their lifetime. At first presentation, seizures were classified as Febrile Convulsion, Acute Symptomatic Seizure or Single Unprovoked Seizure. The seizure classification was revised to include Epilepsy if seizures recurred. Thirty-eight persons in the JSSCD (N = 543) were identified with seizures. The 5-year cumulative incidence of febrile convulsions was 2·2%. The incidence rate of epilepsy (all genotypes) was 100/100 000 person-years, 139/100 000 for the SS genotype. Despite limited availability of diagnostic investigations, clinical seizures were associated with increased all-cause mortality. Male gender (Odds Ratio [OR]: 4·0[95% confidence interval [CI]; 1·03-20·0]) and dactylitis in childhood (OR: 17·4 [95% CI; 4·82-62·85]) were associated with increased risk of developing epilepsy. Epilepsy in persons with SCD is 2-3 times more common than in non-sickle populations and is associated with increased all-cause mortality in all sickle cell genotypes.