Dotson Vonetta M, Davatzikos Christos, Kraut Michael A, Resnick Susan M
Laboratory of Personality and Cognition, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
J Psychiatry Neurosci. 2009 Sep;34(5):367-75.
Late-life depression is associated with decreased brain volumes, particularly in frontal and temporal areas. Evidence suggests that depressive symptoms at a subclinical level are also associated with brain atrophy in these regions, but most of these associations are based on cross-sectional data. Our objective was to investigate both cross-sectional and longitudinal relations between sub-threshold depressive symptoms and brain volumes in older adults and to examine whether these associations are modified by age.
In total, 110 dementia-free adults from the neuroimaging substudy of the Baltimore Longitudinal Study of Aging aged 56 years and older at baseline participated in this study. Participants received annual evaluations for up to 9 years, during which structural magnetic resonance imaging (MRI) scans were acquired and depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale.
Mean depressive symptom scores over time were associated with grey matter volume reductions in the left temporal lobe. Depressive symptoms were associated with brain volume reductions with advancing age in the cingulate gyrus and orbitofrontal cortex. Moreover, individuals with higher mean depressive symptom scores showed a faster rate of volume decline in left frontal white matter. Depressive symptoms were not associated with hippocampus volumes.
Limitations include the relative homogeneity of our primarily white and highly educated sample, the lack of information about age at onset of depressive symptoms and potential limitations of the automated brain volume registration.
Our results suggest that depressive symptoms, even at a subthreshold level, are associated with volume reductions in specific frontal and temporal brain regions, particularly with advancing age.
老年期抑郁症与脑容量减少有关，尤其是额叶和颞叶区域。有证据表明，亚临床水平的抑郁症状也与这些区域的脑萎缩有关，但这些关联大多基于横断面数据。我们的目的是研究老年人亚阈值抑郁症状与脑容量之间的横断面和纵向关系，并探讨这些关联是否因年龄而有所不同。
共有110名来自巴尔的摩老年纵向研究神经影像学子研究的无痴呆成年人参与了本研究，他们在基线时年龄在56岁及以上。参与者接受了长达9年的年度评估，在此期间进行了结构磁共振成像（MRI）扫描，并使用流行病学研究中心抑郁量表测量了抑郁症状。
随着时间推移，平均抑郁症状评分与左侧颞叶灰质体积减少有关。抑郁症状与扣带回和眶额皮质中随着年龄增长的脑容量减少有关。此外，平均抑郁症状评分较高的个体左侧额叶白质体积下降速度更快。抑郁症状与海马体体积无关。
局限性包括我们主要为白人且受过高等教育的样本相对同质，缺乏抑郁症状发病年龄的信息以及自动脑容量登记的潜在局限性。
我们的结果表明，即使是亚阈值水平的抑郁症状也与特定额叶和颞叶脑区的体积减少有关，尤其是随着年龄的增长。
