The survival of young children with sickle cell disease (SCD) has improved, but less is known about older children and adolescents. We studied the Dallas Newborn Cohort (DNC) to estimate contemporary 18-year survival for newborns with SCD and document changes in the causes and ages of death over time. We also explored whether improvements in the quality of medical care were temporally associated with survival. The DNC now includes 940 subjects with 8857 patient-years of follow-up. Most children with sickle cell anemia (93.9%) and nearly all children with milder forms of SCD (98.4%) now live to become adults. The incidence of death and the pattern of mortality changed over the duration of the cohort. Sepsis is no longer the leading cause of death. All the recent deaths in the cohort occurred in patients 18 years or older, most shortly after the transition to adult care. Quality of care in the DNC has improved over time, with significantly more timely initial visits and preventive interventions for young children. In summary, most children with SCD now survive the childhood years, but young adults who transition to adult medical care are at high risk for early death.

Silent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). We tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular blood-transfusion therapy than among those who received standard care. In this randomized, single-blind clinical trial, we randomly assigned children with sickle cell anemia to receive regular blood transfusions (transfusion group) or standard care (observation group). Participants were between 5 and 15 years of age, with no history of stroke and with one or more silent cerebral infarcts on magnetic resonance imaging and a neurologic examination showing no abnormalities corresponding to these lesions. The primary end point was the recurrence of an infarct, defined as a stroke or a new or enlarged silent cerebral infarct. A total of 196 children (mean age, 10 years) were randomly assigned to the observation or transfusion group and were followed for a median of 3 years. In the transfusion group, 6 of 99 children (6%) had an end-point event (1 had a stroke, and 5 had new or enlarged silent cerebral infarcts). In the observation group, 14 of 97 children (14%) had an end-point event (7 had strokes, and 7 had new or enlarged silent cerebral infarcts). The incidence of the primary end point in the transfusion and observation groups was 2.0 and 4.8 events, respectively, per 100 years at risk, corresponding to an incidence rate ratio of 0.41 (95% confidence interval, 0.12 to 0.99; P=0.04). Regular blood-transfusion therapy significantly reduced the incidence of the recurrence of cerebral infarct in children with sickle cell anemia. (Funded by the National Institute of Neurological Disorders and Stroke and others; Silent Cerebral Infarct Multi-Center Clinical Trial ClinicalTrials.gov number, NCT00072761, and Current Controlled Trials number, ISRCTN52713285.)

Contemporary survival data are not available for children with sickle cell disease (SCD). The few previous childhood SCD cohort studies do not reflect the benefits of modern therapy. We defined an inception cohort of newborns with sickle cell anemia (SS), sickle-β°-thalassemia (S β°), sickle-hemoglobin C disease (SC), or sickle-β+-thalassemia (Sβ+) who were identified by newborn screening and followed for up to 18 years. The incidence of death and stroke were calculated. Overall survival, SCD-related survival (considering only SCD-related deaths), and strokefree survival were determined. The 711 subjects provided 5648 patient-years of observation. Twenty-five subjects died; mean age at death was 5.6 years. Five patients died from infection. Thirty had at least one stroke. Among SS and Sβ° subjects (n = 448), the overall rates of death and stroke were 0.59 and 0.85/100 patient-years. Survival analysis of SS and Sβ° subjects predicted the cumulative overall, SCD-related, and stroke-free survival to be 85.6%, 93.6%, and 88.5% by 18 years of age. No SCD-related deaths or strokes occurred in SC or Sβ+ subjects (n = 263). Childhood mortality from SCD is decreasing, the mean age at death is increasing, and a smaller proportion of deaths are from infection.

The most common form of neurologic injury in sickle cell anemia (SCA) is silent cerebral infarction (SCI). In the Silent Cerebral Infarct Multi-Center Clinical Trial, we sought to identify risk factors associated with SCI. In this cross-sectional study, we evaluated the clinical history and baseline laboratory values and performed magnetic resonance imaging of the brain in participants with SCA (HbSS or HbSβ° thalassemia) between the ages of 5 and 15 years with no history of overt stroke or seizures. Neuroradiology and neurology committees adjudicated the presence of SCI. SCIs were diagnosed in 30.8% (251 of 814) participants who completed all evaluations and had valid data on all prespecified demographic and clinical covariates. The mean age of the participants was 9.1 years, with 413 males (50.7%). In a multivariable logistic regression analysis, lower baseline hemoglobin concentration (P < .001), higher baseline systolic blood pressure (P = .018), and male sex (P = .030) were statistically significantly associated with an increased risk of an SCI. Hemoglobin concentration and systolic blood pressure are risk factors for SCI in children with SCA and may be therapeutic targets for decreasing the risk of SCI. This study is registered at www.clinicaltrials.gov as #NCT00072761.

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. Am. J. Hematol. 89:162–167, 2014.

PURPOSE: Folate deficiency, either by diet or drug, increases plasma homocysteine (Hcy). Hcy damages cerebrovascular endothelium, and hyperhomocysteinemia is a risk factor for stroke. Hcy is metabolized to excitatory amino acid (EAA) neurotransmitters, such as homocysteic acid (HCA) and cysteine sulfinic acid (CSA), which may cause seizures and excitotoxic neuronal death. We postulated that excess Hcy and EAA neurotransmitters may partly mediate methotrexate (MTX)-associated neurotoxicity. PATIENTS AND METHODS: In this retrospective analysis, we used high-performance liquid chromatography (HPLC) to measure Hcy, HCA, and CSA in CSF from two groups of children: (1) a control group of patients with no MTX exposure, and (2) a treatment group of patients who had received MTX no more than 7 days before a scheduled lumbar puncture. RESULTS: The treatment group had a significantly (P = .0255) greater concentration of Hcy in CSF (0.814 micromol/L +/- 0.215 [mean +/- SEM], n = 23) than the control group (0.210 micromol/L +/- 0.028, n = 34). HCA and CSA were not detected in CSF from control patients (n = 29); however, MTX caused marked accumulation of CSF HCA (119.1 micromol/L +/- 32.0, n = 16) and CSA (28.4 micromol/L +/- 7.7, n = 16) in the treatment group. Patients with neurologic toxicity at the time of lumbar puncture had many of the highest concentrations of Hcy, HCA, and CSA. CONCLUSION: These data support our hypothesis that MTX-associated neurotoxicity may be mediated by Hcy and excitotoxic neurotransmitters.