Cocaine, anemia, and neurodevelopmental outcomes in children: a longitudinal study

This longitudinal study investigated the rates of iron-deficiency (ID) and iron-deficiency anemia (IDA) among prenatally cocaine-exposed and nonexposed two- and four-year-old children and assessed their relationships to neurodevelopmental outcomes. The sample consisted of 143 two-year-old (70 exposed and 73 nonexposed) and 274 four-year-old (139 exposed and 135 nonexposed) low socioeconomic status children recruited from an ongoing longitudinal study. Hematological assessments included hemoglobin, serum ferritin, mean corpuscular volume, transferrin saturation, and blood lead levels. The neurodevelopmental outcomes consisted of the Bayley Mental (MDI) and Motor (PDI) Development indices at two years, and the Wechsler Preschool and Primary Scales of Intelligence (WPPSI) and the Peabody Developmental Motor Scales (PDMS) at four years. The rate of IDA in four-year-old children was significantly greater among the cocaine-exposed compared to the nonexposed group (p =.026), while the rates at two years were not significant. Exposure to IDA at two years was associated with a significant decrease in concurrent motor scores (p =.011) after adjustment for relevant covariates. Peak exposure to IDA, defined as being anemic at 2 and/or 4 years of age, was associated with a significant (p <.05) decrease in Full Scale IQ after adjustment. Cocaine exposure was not a significant predictor of Full Scale IQ with the inclusion of peak IDA and lead in the model. These findings indicate the need for greater pediatric surveillance of IDA and lead in cocaine-exposed infants, in order to reduce long-term neuropsychological deficits.