目的：咸信認知障礙會影響重鬱症病人的長期失能。本研究是描述台灣憂鬱症病人的認知障礙。方法：多中心、橫斷面研究(CogDAD)之中，針對國立成功大學附設醫院招募的226位病人進行次群體分析。主研究之主結果已經刊登了(Srisurapanont et al, 2017)。本分析是針對其中台灣病人的憂鬱程度、認知障礙、以及失能，進行評估與描述。結果：相較於主研究的樣本病人，台灣樣本病人年紀約年長五歲（50.8±10.8歲對46.5±12.5歲）、本次發作病程時間較長（自陳本次發作八週以上的比率，96%對82.2%），在研究開始前，有接受治療（92.5%對86.7%）以及持續治療（79.2%對74.8%）的比率都較高。台灣病人的憂鬱嚴重度較低（以九題病人健康問卷測量，10.04±6.95對11.27±6.92），並且自陳知覺到的認知障礙程度較輕（以知覺失能問卷—憂鬱測量，16.27±15.23對22.59±16.16）。雖然台灣病人報告的失能程度與曠職天數都較少，無生產力的天數與全體樣本病人的數目相當。共變數分析顯示，在控制憂鬱嚴重度之後，工作／就學上的功能減損，分別與認知障礙(p ＜ 0.05)與住院史(p ＜ 0.01)顯著的有關。結論：本研究顯示，改善認知障礙以及病人功能是治療台灣憂鬱症病人的重要目標。

Objectives: Cognitive dysfunction can remarkably contribute to long-term functional disability in major depressive disorder (MDD). In this study, we intended to assess and to describe cognitive dysfunction of the Taiwanese MDD patients of the Cognitive Dysfunction in Asian patients with Depression (Cog- DAD). Methods: This is a subgroup analysis of 226 Taiwanese patients recruited from National Cheng Kung University Hospital, Tainan, Taiwan of the multi-center, cross-sectional CogDAD study. Results of the CogDAD study primary analyses are reported elsewhere (Srisurapanont et al, 2017). The present subgroup analysis assessed and described depression severity, cognitive dysfunction, and functional disability in the Taiwanese population. Results: Compared to the overall CogDAD study population, Taiwanese patients were about five years older (50.8 ± 10.8 vs. 46.5 ± 12.5 years) and had a longer duration of current depressive episode (96% vs. 82.2%) and reported a depressive episode of more than eight weeks in duration, with a higher proportion who were already being treated before the study visit (92.5% vs. 86.7%) and were maintained on treatment (79.2% vs. 74.8%). Accordingly, Taiwanese patients had lower severity of depression (10.04 ± 6.95 vs. 11.27 ± 6.92 in scores of Patient Health Questionnaire 9-item) and reported less severe perceived cognitive dysfunction (16.27 ± 15.23 vs. 22.59 ± 16.16 in scores of Perceived Deficit Questionnaire-Depression). Taiwanese patients showed less severe functional disability and fewer days lost (absenteeism), but their number of unproductive days (presenteeism) was similar to that in the overall CogDAD study population. After controlling for depression severity, functional disability at work/school was significantly independently associated with cognitive dysfunction (p ＜ 0.05) and history of hospitalization (p ＜ 0.01). Conclusion: This study reflects the importance of treating Taiwanese MDD patients with the aim of improving cognitive dysfunction and patient functioning.