Hsiao P H, Chiu Y N, Tsai W Y, Su S C, Lee J S, Soong W T
Department of Pediatrics, National Taiwan University Hospital, 7 Chung-Shan South Road, Taipei, Taiwan.
J Formos Med Assoc. 2001 Jan;100(1):40-4.
Mental retardation is a major sequela of delayed treatment for congenital hypothyroidism; congenital hypothyroidism can be treated early if detected with neonatal screening. We evaluated the intellectual outcomes of 62 patients with congenital hypothyroidism detected by neonatal screening at a major teaching hospital in northern Taiwan. The effects of thyroid pathology, age at the initiation of treatment, socioeconomic status, and severity of hypothyroidism on intellectual outcome were also analyzed.
All patients had euthyroid status at the time of intelligence testing. The Chinese Fourth Revision of the Binet-Simon Scales was used to evaluate the patients' intelligence between the ages of 3 and 6 years.
The mean intelligence quotient (IQ) score was 102 +/- 18. Only four of the 62 patients were mentally retarded. Patients with lower initial serum thyroxine concentrations (T4; < 2 micrograms/dL) at the time of diagnosis of congenital hypothyroidism had significantly lower IQs (95 +/- 19, n = 26) than those with higher initial T4 concentrations (106 +/- 16, n = 36; p < 0.05). Patients with fewer than three ossification centers had lower IQs (91 +/- 20, n = 12) than those with three or more (104 +/- 17, n = 36; p < 0.05). Significantly lower IQs were also found in patients with a smaller femoral epiphysis area (< 0.1 cm2) (92 +/- 20, n = 15) than in those with larger epiphyses (106 +/- 15, n = 21; p < 0.05). The type of pathology (ectopia, athyrosis, dyshormonogenesis), age at the start of treatment (before or after 30 days of age), and socioeconomic status did not significantly affect the intellectual outcome.
Our results indicate that intellectual outcome in Taiwanese patients with congenital hypothyroidism has been improved by neonatal screening and that the severity of hypothyroidism at diagnosis is the most important prognostic factor affecting intellectual outcome in these patients.
智力发育迟缓是先天性甲状腺功能减退症治疗延迟的主要后遗症；如果通过新生儿筛查得以发现，先天性甲状腺功能减退症可得到早期治疗。我们评估了在台湾北部一家大型教学医院通过新生儿筛查发现的62例先天性甲状腺功能减退症患者的智力发育结果。还分析了甲状腺病理、开始治疗的年龄、社会经济状况以及甲状腺功能减退症的严重程度对智力发育结果的影响。
所有患者在进行智力测试时甲状腺功能均正常。采用中国比内-西蒙量表第四次修订版评估3至6岁患者的智力。
平均智商（IQ）得分为102±18。62例患者中只有4例智力发育迟缓。先天性甲状腺功能减退症诊断时初始血清甲状腺素浓度（T4；<2微克/分升）较低的患者智商（95±19，n = 26）显著低于初始T4浓度较高的患者（106±16，n = 36；p<0.05）。骨化中心少于3个的患者智商（91±20，n = 12）低于骨化中心有3个或更多的患者（104±17，n = 36；p<0.05）。股骨骨骺面积较小（<0.1平方厘米）的患者智商（92±20，n = 15）也显著低于骨骺较大的患者（106±15，n = 21；p<0.05）。病理类型（异位、无甲状腺、激素合成障碍）、开始治疗的年龄（30日龄之前或之后）以及社会经济状况对智力发育结果无显著影响。
我们的结果表明，新生儿筛查改善了台湾先天性甲状腺功能减退症患者的智力发育结果，并且诊断时甲状腺功能减退症的严重程度是影响这些患者智力发育结果的最重要预后因素。
