Intellectual development of children with renal insufficiency and end stage disease.

Sixty six pediatric nephrology patients, age 6 months to 20 years, were given individual psychometric tests of intelligence two or more times during the course of treatment; 24 were retested within the stage of conservative management, dialysis or post-transplantation, 42 were retested between those stages. The first IQ scores ranged from three standard deviations below the test mean of 100 to two above (first sample mean 85.91). The second mean IQ was significantly higher (91.96). Paired t tests showed that significant increases in mean IQ scores occurred between the pre- to post-transplantation stages of treatment. No significant changes occurred within stages or between conservative management and dialysis. Equivocal changes existed between dialysis and transplantation. Four patients with prolonged central nervous system complications and serious family problems had scores which declined more than one standard deviation. Issues related to age, medical condition, socioeconomic status, and cohort changes were evaluated.