Supplementary Material for: Efficacy of Cognitive Behaviour Therapy versus Anxiety Management for Body Dysmorphic Disorder: A Randomised Controlled Trial

<b><i>Background:</i></b> The evidence base for the efficacy of cognitive behaviour therapy (CBT) for treating body dysmorphic disorder (BDD) is weak. <b><i>Aims:</i></b> To determine whether CBT is more effective than anxiety management (AM) in an outpatient setting. <b><i>Method:</i></b> This was a single-blind stratified parallel-group randomised controlled trial. The primary endpoint was at 12 weeks, and the Yale-Brown Obsessive Compulsive Scale for BDD (BDD-YBOCS) was the primary outcome measure. Secondary measures for BDD included the Brown Assessment of Beliefs Scale (BABS), the Appearance Anxiety Inventory (AAI) and the Body Image Quality of Life Inventory (BIQLI). The outcome measures were collected at baseline and week 12. The CBT group, unlike the AM group, had 4 further weekly sessions that were analysed for their added value. Both groups then completed measures at their 1-month follow-up. Forty-six participants with a DSM-IV diagnosis of BDD, including those with delusional BDD, were randomly allocated to either CBT or AM. <b><i>Results:</i></b> At 12 weeks, CBT was found to be significantly superior to AM on the BDD-YBOCS [β = -7.19; SE (β) = 2.61; p &lt; 0.01; 95% CI = -12.31 to -2.07; d = 0.99] as well as the secondary outcome measures of the BABS, AAI and BIQLI. Further benefits occurred by week 16 within the CBT group. There were no differences in outcome for those with delusional BDD or depression. <b><i>Conclusions:</i></b> CBT is an effective intervention for people with BDD even with delusional beliefs or depression and is more effective than AM over 12 weeks.

背景：目前针对认知行为疗法（Cognitive Behaviour Therapy, CBT）治疗躯体变形障碍（Body Dysmorphic Disorder, BDD）的疗效循证依据较为薄弱。

目的：明确在门诊环境中，认知行为疗法相较于焦虑管理（Anxiety Management, AM）是否更具疗效。

方法：本研究为单盲、分层、平行组随机对照试验。主要观察终点为12周时点，主要疗效指标为用于躯体变形障碍的耶鲁-布朗强迫症量表（Yale-Brown Obsessive Compulsive Scale for BDD, BDD-YBOCS）。躯体变形障碍的次要疗效指标包括布朗信念评估量表（Brown Assessment of Beliefs Scale, BABS）、外表焦虑量表（Appearance Anxiety Inventory, AAI）以及躯体形象生活质量量表（Body Image Quality of Life Inventory, BIQLI）。所有疗效指标均于基线及第12周时采集。与焦虑管理组不同，认知行为疗法组额外开展了4次每周1次的干预疗程，以分析其附加干预价值。两组受试者均在1个月随访时点完成疗效指标评估。本研究共纳入46名符合DSM-IV诊断标准的躯体变形障碍患者（包括妄想性躯体变形障碍患者），并将其随机分配至认知行为疗法组或焦虑管理组。

结果：在12周时点，认知行为疗法组在躯体变形障碍耶鲁-布朗强迫症量表[β = -7.19；标准误(SE) = 2.61；p < 0.01；95%置信区间(CI)为-12.31~-2.07；效应量d = 0.99]以及布朗信念评估量表、外表焦虑量表、躯体形象生活质量量表等次要疗效指标上均显著优于焦虑管理组。认知行为疗法组的疗效获益在第16周时进一步显现。对于合并妄想性躯体变形障碍或抑郁症状的患者，两组疗效无显著差异。

结论：认知行为疗法是治疗躯体变形障碍的有效干预手段，即便患者存在妄想性信念或共病抑郁亦能发挥作用；且在12周干预周期内，其疗效优于焦虑管理。