Neuropsychologic performance in school-aged children with sickle cell disease: A report from the Cooperative Study of Sickle Cell Disease

Objectives: To compare the results of serial neuropsychologic testing in ch ildren with sickle cell disease with the results of serial magnetic resonan ce imaging (MRI) examinations, particularly to evaluate neuropsychologic fu nction in die absence of overt stroke. Study design: In the Cooperative Study of Sickle Cell Disease, serial neuro psychologic and MRI tests were performed in 373 patients (255 with hemoglob in SS and 118 with hemoglobin SC), 6 to 18 years of age. MRI of the brain a nd a neuropsychologic battery that included the Wechsler Intelligence Scale for Children (WISC-R or WISC-III) and the Woodcock-Johnson Math and Readin g Achievement Tests were performed concurrently and repeated every 2 to 3 y ears. A silent infarct was defined as an MRI finding of increased signal In tensity on T-2 imaging in a patient without a history of stroke. Results: Twenty-seven patients, all with hemoglobin SS, had overt strokes a nd 62 had silent infarcts (52 with hemoglobin SS). Patients with hemoglobin SS and silent infarcts had significantly lower scores for math and reading achievement, Full-Scale IQ Verbal IQ and Performance IQ when compared with those with normal MRI findings. In children with hemoglobin SS and normal MRI findings, the scores for Verbal IQ math achievement, and coding (a subs cale of Performance IQ) declined with increasing age. Conclusions: School-aged children with sickle cell disease had compromised neuropsychologic function in the presence of silent infarcts. In addition, they had declines in performance in certain areas of function over time. Th erapeutic interventions that prevent or lessen cognitive impairment are nee ded before school entry for children with sickle cell disease.