Serum cholesterol in mental retardation.
Examination of serum cholesterol values from over 1,400 mentally retarded patients revealed that these results were significantly lower than corresponding results from normal subjects, and that the male patients had significantly lower results than the female patients. There appeared to be no significant correlation between serum cholesterol values and IQ, systolic or diastolic blood pressures, drugs used in treatment, presence or absence of epilepsy. There was no clinical evidence of underlying hyperthyroidism. Patients with Down's syndrome and phenylketonuria did not appear to have serum cholesterol values outside the range found for the other patients. The significance of these findings and possible causes for the low cholesterol values are discussed.