Objective: Neurodevelopmental deficits are among the serious complications of sickle cell disease (SCD). However, few studies have prospectively evaluated neurodevelopmental deficits in very young children with SCD. We analyzed baseline neurodevelopmental data from a cohort of 80 infants and toddlers with SCD to identify primary disease-related events and sociodemographic risk factors associated with early developmental delay.
Methods: This is an analysis of baseline date of a 4-year mixed, cross-sectional/longitudinal study. Full-term children at age 3.5 years or younger with SCD (any genotype) were eligible. Neurodevelopmental evaluations (Bayley II) were conducted at ages 9, 15, 21, 30, and 40 months. Demographics, hematologic variables, and medical events were obtained.
Results: Significant neurodevelopmental deficits were evident: 17.5% scoring >2SD below the mean on Bayley Mental Index or Motor Index. Odds ratio of significant developmental delay was >9 times more likely among those who had experienced vaso-occlusive pain episodes, after controlling for socioeconomic status (SES), gender, pneumonia/acute chest syndrome, and hemoglobin concentration. Male gender was also a risk factor for developmental delay.
Conclusions: Early cognitive and motor delays were present in young children with SCD, with higher prevalence among those who had experienced pain crises. Increased vulnerability of male gender is consistent with other at-risk populations but has not been previously addressed in SCD research. Furthermore, these delays are not sufficiently explained by lower SES. Significant developmental delay in children with SCD may go unrecognized by primary care practices, medical specialty clinics, or parents. The importance of routine neurodevelopmental assessment for children with chronic medical conditions is clear.
*Child Development Program/Department of Psychiatry and Behavioral Sciences, Center for Neuroscience and Behavioral Medicine, Children's National Medical Center;
†Children's Research Institute, Center for Clinical and Community Research, Children's National Medical Center;
‡Division of Hematology, Center for Cancer and Blood Disorders, Children's National Medical Center, Washington, DC;
§Sickle Cell Center, University of Illinois, Chicago, IL;
‖Department of Pediatrics and Child Health, Howard University College of Medicine, Washington, DC.
Address for reprints: Penny Glass, PhD, Child Development Program, Children's National Medical Center, 111 Michigan Avenue NW Room 3800, Washington, DC 20010; e-mail: firstname.lastname@example.org.
Disclosure: The authors declare no conflict of interest.
Our clinical research project was part of the Washington Area Basic and Translational Research Program in Sickle Cell Disease supported by National Heart Lung and Blood Institute Grant No. U54-HL090508 (PI Dr. Victor Gordeuk). This publication was made possible by Grant M01-RR020359 from the National Center for Research Resources (NCRR), Award Number UL1-RR031988 from NCRR, the Georgetown-Howard Universities Center for Clinical and Translational Science Supported by NCRR Grant 1UL1-RR031975-01 and the Children's National Medical Center's NCRR Grant ULITR000075. The contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health.
Received January 11, 2013
Accepted May 16, 2013