Intellectual, school and occupational performance in patients with idiopathic hypothalamo-pituitary hypothyroidism and primary hypothyroidism.
Intelligence quotient (IQ), school and professional performance were reviewed in 33 patients with idiopathic hypothalamo-pituitary hypothyroidism. Diagnosis was based on low T4 values and clinical signs. All were treated with growth hormone (HGH). In some, hypothyroidism became manifest only after HGH therapy. Birth history revealed breech delivery in 24 and perinatal asphyxia in 15 of them. Thyroid treatment was started at a mean age of 9.8 (range 4-18 years). The mean IQ was 103.4 +/- 16.7 (SD). 9 patients had IQs below 90, 8 of them were born by breech delivery, 3 had severe perinatal asphyxia, one recurrent symptomatic hypoglycemia, and one a micropenis. Of those patients who have reached the respective age, 7 attended college, 3 university, and 9 had skilled professions. Only 7 required special education. For comparison, 52 patients with primary hypothyroidism were studied. Their mean IQ was with 89.3 +/- 18.1 (SD) significantly lower (p < 0.001) than the mean IQ of patients with hypothalamo-pituitary hypothyroidism. The best IQ (96.8 +/- 16.9) was attained when thyroid treatment was started before the age of 4 months, the lowest IQ (78.2 +/- 19.2) was found in the group of patients in whom thyroid substitution was initiated between 5 and 12 months. Patients who were treated after one year of age, had a mean IQ of 90.0 +/- 15.7. This group includes patients with ectopic thyroid glands or acquired hypothyroidism such as Hashimoto's thyroiditis.
D000293:Adolescent; D000328:Adult; D002648:Child; D004522:Educational Status; D005260:Female; D006801:Humans; D007018:Hypopituitarism / Q000150:complications*; D007030:Hypothalamo-Hypophyseal System; D007037:Hypothyroidism / Q000188:drug therapy / Q000209:etiology / Q000523:psychology*; D007360:Intelligence; D008297:Male; D009790:Occupations; D013963:Thyroid Hormones / Q000008:administration & dosage
D013963:Thyroid Hormones