Heydebrand Gitry
Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Curr Opin Psychiatry. 2006 May;19(3):277-81. doi: 10.1097/01.yco.0000218598.38807.b0.
Studies of first-degree relatives of patients with schizophrenia over the past 25 years have reported a number of cognitive deficits, primarily in the domains of memory and executive function. Nevertheless, due to a number of methodological issues, such as including different types of relatives and not controlling for possible psychopathology, it is not yet clear that these findings can fully support a conclusion of heritability of cognitive dysfunction associated with a schizophrenia genotype.
Several recent meta-analyses have shown that the most consistent deficit shown by relatives is impaired performance on 'maintenance plus' frontal-lobe tasks requiring increased effort and higher central executive processing. Studies of multiplex families (multiple diagnoses in one family) also report that family members tend to have more difficulty on executive function tasks. Another interesting trend is research on subgroups of patients and relatives displaying distinct cognitive syndromes, particularly a subgroup with a generalized cognitive deficit.
As methodological designs improve, this field of study holds promise not only for understanding the neurobiological mechanisms of schizophrenia and the associated cognitive deficits, but also for possibly describing endophenotypes that may lead to identifying at-risk patients and relatives.
过去25年对精神分裂症患者一级亲属的研究报告了一些认知缺陷，主要存在于记忆和执行功能领域。然而，由于一些方法学问题，如纳入不同类型的亲属且未控制可能的精神病理学因素，目前尚不清楚这些发现能否充分支持与精神分裂症基因型相关的认知功能障碍具有遗传性这一结论。
近期的几项荟萃分析表明，亲属表现出的最一致的缺陷是在需要更多努力和更高中央执行处理能力的“维持加”额叶任务上表现受损。对多重家庭（一个家庭中有多种诊断）的研究也报告称，家庭成员在执行功能任务上往往更困难。另一个有趣的趋势是对表现出不同认知综合征的患者和亲属亚组的研究，特别是一个具有广泛性认知缺陷的亚组。
随着方法学设计的改进，这一研究领域不仅有望理解精神分裂症的神经生物学机制及相关认知缺陷，还可能描述出可能有助于识别高危患者和亲属的内表型。
