Parent education and biologic factors influence on cognition in sickle cell anemia

Abstract

Children with sickle cell anemia have a high prevalence of silent cerebral infarcts (SCIs) that are associated with decreased full-scale intelligence quotient (FSIQ). While the educational attainment of parents is a known strong predictor of the cognitive development of children in general, the role of parental education in sickle cell anemia along with other factors that adversely affect cognitive function (anemia, cerebral infarcts) is not known. We tested the hypothesis that both the presence of SCI and parental education would impact FSIQ in children with sickle cell anemia. A multicenter, cross-sectional study was conducted in 19 US sites of the Silent Infarct Transfusion Trial among children with sickle cell anemia, age 5–15 years. All were screened for SCIs. Participants with and without SCI were administered the Wechsler Abbreviated Scale of Intelligence. A total of 150 participants (107 with and 43 without SCIs) were included in the analysis. In a multivariable linear regression model for FSIQ, the absence of college education for the head of household was associated with a decrease of 6.2 points (P=0.005); presence of SCI with a 5.2 point decrease (P=0.017); each $1000 of family income per capita with a 0.33 point increase (P=0.023); each increase of 1 year in age with a 0.96 point decrease (P=0.023); and each 1% (absolute) decrease in hemoglobin oxygen saturation with 0.75 point decrease (P=0.030). In conclusion, FSIQ in children with sickle cell anemia is best accounted for by a multivariate model that includes both biologic and socioenvironmental factors.

Low fetal hemoglobin percentage is associated with silent brain lesions in adults with homozygous sickle cell disease

“…29 Beyond the term "silent," which simply indicates the absence of a history of stroke, children who have silent brain lesions on brain MRI scans have been shown to have poorer cognitive function than do children who have normal brain MRI findings. Indeed, in children with SCD, such "silent" lesions have been shown to be associated with a mean decrease in full-scale IQ of 5 points, 30 poor academic performance, 31 and a higher risk of overt strokes. Values are mean (6 SD), unless otherwise indicated.…”

Reconsideration of Age as a Contraindication for Curative Therapy of Sickle Cell Disease

“…Among children with sickle cell anemia, results from the Silent Infarct Transfusion Trial predict an average decrease of a child's intelligence quotient (IQ) by 1 point per year, regardless of the presence of a silent cerebral infarct. 16 Given the relationship between IQ and career attainment, these outcomes are equally important to those with sickle cell disease.…”

Neurological Complications and MRI

“…haematocrit <20%) have shown poorer performance on both verbal and performance aspects of IQ [119], and have accounted for a significant proportion of variance in FSIQ [64,138] and executive functions [64].Low nocturnal peripheral oxygen saturation was associated with reduced performance on the Tower of London test, which measures strategic planning and rule learning [139]. In the baseline data from the Silent Infarct Trial, a 1% reduction in daytime oxygen saturation was associated with a reduction in 0.75 full scale IQ points [122].…”

“…Large cohort studies have found socioeconomic status and parent education as major predictors of cognitive function, rather than SCI [122,141].…”

“…With the routine use of MRI added in the mid-1990s, patients were classed into groups based on history of stroke and presence or absence of SCI [42]; since then, several studies have confirmed that children with SCI generally have lower IQ scores than those without evi-dence of SCI [86,92,[118][119][120][121]. Recent meta-analyses have found children with history of stroke perform significantly worse than those with SCI by 10 IQ points, children with SCI perform significantly worse than children with normal MRI by 5-6 IQ points [122] and children with normal MRI perform significantly worse than healthy controls by approximately 7 IQ points [8] (Figure 8).…”