Beasley M G, Costello P M, Smith I
DH Phenylketonuria Register, Institute of Child Health, London, UK.
Q J Med. 1994 Mar;87(3):155-60.
Intellectual status at 18 years is reported in 192 patients with phenylketonuria born in the UK between 1964 and 1971, together with their school progress. Mean IQs expressed as standard deviation scores (IQ-SDS) were significantly below estimated population norms, and showed a small decrease from 14 to 18 years of age (mean IQ-SDS -1.06 +/- 1.3 at 14 years and -1.28 +/- 1.07 at 18 years, t = 5.7, p < 0.0001). At 18 years, 27% of subjects had IQs over 2 SDs below the estimated population mean. IQ-SDS at 18 years, although significantly related to average phenylalanine control both between birth and 14 years, and between 14 and 18 years, was not independently related to either variable after allowing for IQ-SDS at 14 years. We conclude that general ability in young adults with early treated phenylketonuria, although reduced in comparison with their peers and closely related to phenylalanine control in early childhood, is not directly influenced by phenylalanine control in the four years preceding the 18th birthday. The apparent fall in IQ-SDS between 14 and 18 years may be due to methodological problems in the analysis of longitudinal IQ data without a control group, rather than providing evidence of intellectual decline.
报告了192例于1964年至1971年间在英国出生的苯丙酮尿症患者18岁时的智力状况及其在校学习进展情况。以标准差分数表示的平均智商（IQ-SDS）显著低于估计的总体常模，并且从14岁到18岁有小幅下降（14岁时平均IQ-SDS为-1.06±1.3，18岁时为-1.28±1.07，t = 5.7，p < 0.0001）。18岁时，27%的受试者智商低于估计总体均值2个标准差。18岁时的IQ-SDS，虽然在出生至14岁以及14至18岁期间均与苯丙氨酸平均控制水平显著相关，但在考虑14岁时的IQ-SDS后，与这两个变量均无独立相关性。我们得出结论，早期接受治疗的苯丙酮尿症青年的一般能力，虽然与同龄人相比有所降低且与幼儿期苯丙氨酸控制密切相关，但在18岁生日前的四年中不受苯丙氨酸控制的直接影响。14至18岁之间IQ-SDS的明显下降可能是由于在没有对照组的情况下对纵向智商数据进行分析时存在方法学问题，而非表明存在智力衰退。
