Division of Psychiatry, University of Edinburgh, Edinburgh, United Kingdom.
Department of Psychology, University of Edinburgh, Edinburgh, United Kingdom.
Eur Psychiatry. 2020 Feb 21;63(1):e28. doi: 10.1192/j.eurpsy.2020.24.
Cognitive impairment associated with lifetime major depressive disorder (MDD) is well-supported by meta-analytic studies, but population-based estimates remain scarce. Previous UK Biobank studies have only shown limited evidence of cognitive differences related to probable MDD. Using updated cognitive and clinical assessments in UK Biobank, this study investigated population-level differences in cognitive functioning associated with lifetime MDD.
Associations between lifetime MDD and cognition (performance on six tasks and general cognitive functioning [g-factor]) were investigated in UK Biobank (N-range 7,457-14,836, age 45-81 years, 52% female), adjusting for demographics, education, and lifestyle. Lifetime MDD classifications were based on the Composite International Diagnostic Interview. Within the lifetime MDD group, we additionally investigated relationships between cognition and (a) recurrence, (b) current symptoms, (c) severity of psychosocial impairment (while symptomatic), and (d) concurrent psychotropic medication use.
Lifetime MDD was robustly associated with a lower g-factor (β = -0.10, PFDR = 4.7 × 10-5), with impairments in attention, processing speed, and executive functioning (β ≥ 0.06). Clinical characteristics revealed differential profiles of cognitive impairment among case individuals; those who reported severe psychosocial impairment and use of psychotropic medication performed worse on cognitive tests. Severe psychosocial impairment and reasoning showed the strongest association (β = -0.18, PFDR = 7.5 × 10-5).
Findings describe small but robust associations between lifetime MDD and lower cognitive performance within a population-based sample. Overall effects were of modest effect size, suggesting limited clinical relevance. However, deficits within specific cognitive domains were more pronounced in relation to clinical characteristics, particularly severe psychosocial impairment.
多项荟萃分析研究证实，与终生重度抑郁症（MDD）相关的认知障碍是存在的，但基于人群的估计仍然很少。之前的英国生物库研究仅显示出与可能的 MDD 相关的认知差异的有限证据。本研究使用英国生物库中更新的认知和临床评估，调查与终生 MDD 相关的认知功能的人群水平差异。
在英国生物库中（N 范围为 7457-14836，年龄 45-81 岁，52%为女性），使用六项任务的认知表现和一般认知功能（g 因素）调查了终生 MDD 与认知之间的关联，并调整了人口统计学、教育和生活方式。终生 MDD 分类基于综合国际诊断访谈。在终生 MDD 组内，我们还调查了认知与（a）复发、（b）当前症状、（c）严重心理社会障碍（有症状时）和（d）同时使用精神药物之间的关系。
终生 MDD 与 g 因素降低（β=-0.10，PFDR=4.7×10-5）显著相关，注意力、处理速度和执行功能受损（β≥0.06）。临床特征揭示了病例个体认知障碍的不同特征；那些报告严重心理社会障碍和使用精神药物的个体在认知测试中表现更差。严重心理社会障碍和推理之间存在最强的关联（β=-0.18，PFDR=7.5×10-5）。
研究结果描述了基于人群的样本中终生 MDD 与较低认知表现之间的小而稳健的关联。总体影响的效应大小适中，表明临床相关性有限。然而，在与临床特征，特别是严重心理社会障碍有关的特定认知领域中，缺陷更为明显。
