双相障碍Ⅰ型核心家系认知功能遗传度研究

Heritability of cognitive functions in nuclear families with bipolar Ⅰ disorder

目的通过核心家系探讨双相障碍Ⅰ型(bipolar I disorder,BD-I)认知功能的遗传性以及与BD可能相关的认知内表型。方法纳入79例稳定期BD-Ⅰ型患者及其健康父母组成的核心家系,以及正常对照140名。采用数字符号测验、数字广度、视觉再生、连线测验(trail making test,TMT)A和B、威斯康星卡片分类测验、言语流畅性、汉诺塔(tower of Hanoi,TOH)评估被试的注意力、处理速率、工作记忆和执行功能等认知功能,采用亲代和子代数量性状回归系数计算家系中各认知指标的遗传度(h^2),并与对照组比较,筛选BD组受损的认知指标。结果控制年龄和受教育年限的混杂影响后,TMT-A错误数(h^2=0.54)、TOH总分(h^2=0.37)、完成任务数(h^2=0.35)的遗传性有统计学意义(均P<0.05)。与对照组比较,患者组上述有遗传性的认知指标中TOH总分、完成任务数指标受损有统计学意义(P<0.05)。结论认知功能中处理速率和执行功能在BD核心家系中可能有遗传性,执行功能指标中TOH总分和完成任务数损害与BD疾病可能相关,可作为BD的内表型。

Objective To examine the heritability of neurocognitive functions in bipolar I disorder（BD-I） families and BD-associated cognitive endophenotypes. Methods Seventy-nine nuclear families consisting of euthymic BD-I probands and their healthy parents were recruited. Cognitive functions including attention, working memory, processing speed and executive function were evaluated by 7 classic neurocognitive tests, and the heritability of neuroconitive functions in these families was estimated using parent-offspring regression indexes of quantitative traits. Furthermore, the heritable cognitions were compared between 79 BD probands and 140 normal controls. Results After adjusted by age and education, mistake numbers of Trail Making Test A（TMT-A）, total score and completed mission numbers of Tower of Hanoi（TOH） were significantly heritable（P〈0.05）. The comparison of these heritable cognitions between patients and normal controls showed that TOH total score and TOH completed mission numbers were significantly impaired in the patient group（P〈0.05）. Conclusion Processing speed and executive function are probably heritable in BD nuclear families. Executive function impairments may be disease-related which could be candidate endophenotypes for bipolar disorder.