Cognitive and fine motor deficits in a pediatric sickle cell disease cohort of mixed ethnic origin

Cerebrovascular disease is an important feature of pediatric sickle cell disease (SCD) and may lead to cognitive and motor impairment. Our cross-sectional study examined the incidence and severity of these impairments in a pediatric cohort without clinical cerebrovascular events from Berlin of mixed ethnic origin. Thirty-two SCD patients (mean age 11.14 years, range 7.0-17.25 years; males 14) were evaluated for full-scale intelligence (IQ) (German version WISC-III), fine motor function (digital writing tablet), and executive function (planning, attention, working memory, and visual-spatial abilities) with the Amsterdam Neuropsychological Tasks (ANT) program and the Tower of London (ToL). Data on clinical risk factors were retrieved from medical records. Full-scale IQ of patients was preserved, whereas performance IQ was significantly reduced (91.19 (SD 12.17) d = 0.7, p = 0.007). SCD patients scored significantly lower than healthy peers when tested for executive and fine motor functions, e.g., planning time in the ToL (6.73 s (SD 3.21) vs. 5.9 s in healthy peers (SD 2.33), d = 0.5, p = <0.001) and frequency on the writing tablet (mean z score -0.79, d = 0.7, p < 0.001). No clinical risk factors were significantly associated with incidence and severity of cognitive and motor deficits. Despite the preservation of full-scale IQ, our SCD cohort of mixed origin exhibited inferior executive abilities and reduced fine motor skills. Our study is limited by the small size of our cohort as well as the lack for control of sociodemographic and socioeconomic factors modulating higher functions but highlights the need for early screening, prevention, and specific interventions for these deficits.