Department of Psychiatry, University of California, San Diego, 92093, USA.
Am J Geriatr Psychiatry. 2011 Jun;19(6):559-70. doi: 10.1097/JGP.0b013e3181ef79f1.
To determine whether early adult cognitive ability is a risk factor for depressive symptoms in midlife and how genetic and environmental influences explain the association and to examine cross-sectional relationships between depressive symptoms and specific cognitive abilities at midlife.
A 35-year longitudinal and cross-sectional twin study of cognitive aging.
Large multicenter study in the United States.
One thousand two hundred thirty-seven male twins aged 51 to 60 years.
At the age of 20 years and midlife, participants completed the same version of a general cognitive ability test (Armed Forces Qualification Test [AFQT]). Midlife testing included an extensive neurocognitive protocol assessing processing speed, verbal memory, visual-spatial memory, working memory, executive function, and visual-spatial ability. Participants completed the Center for Epidemiologic Studies Depression Scale before cognitive testing and provided health and life style information during a medical history interview.
Lower age 20 AFQT scores predicted higher levels of depressive symptoms at age 55 years (r = -0.16,p <0.001). In bivariate twin modeling, 77% of the correlation between early cognitive ability and midlife depressive symptoms was due to shared genetic influences. Controlling for current age, age 20 AFQT, and nonindependence ofobservations, depressive symptoms were associated with worse midlife AFQT scores and poorer performance in all cognitive domains except verbal memory.
Results suggest that low cognitive ability is a risk factor for depressive symptoms; this association is partly due to shared genetic influences. Crosssectional analyses indicate that the association between depressive symptoms and performance is not linked to specific cognitive domains.
确定成年早期认知能力是否是中年抑郁症状的一个风险因素，以及遗传和环境影响如何解释这种关联，并检验中年抑郁症状与特定认知能力之间的横断面关系。
一项对认知衰老的 35 年纵向和横断面双胞胎研究。
美国的一个大型多中心研究。
1237 名年龄在 51 岁至 60 岁之间的男性双胞胎。
在 20 岁和中年时，参与者完成了相同版本的一般认知能力测试（武装部队资格测试[AFQT]）。中年测试包括广泛的神经认知测试，评估处理速度、言语记忆、视觉空间记忆、工作记忆、执行功能和视觉空间能力。参与者在认知测试前完成了《流行病学研究中心抑郁量表》，并在病史访谈期间提供了健康和生活方式信息。
较低的 20 岁 AFQT 分数预测了 55 岁时更高水平的抑郁症状（r=-0.16，p<0.001）。在双变量双胞胎模型中，早期认知能力与中年抑郁症状之间的相关性有 77%是由于共同的遗传影响。在控制当前年龄、20 岁 AFQT 和观测值的非独立性的情况下，抑郁症状与中年 AFQT 分数较差以及所有认知领域（除言语记忆外）的表现较差相关。
结果表明，认知能力低是抑郁症状的一个风险因素；这种关联部分归因于共同的遗传影响。横断面分析表明，抑郁症状与表现之间的关联与特定认知领域无关。
