Background Predictors of antidepressant response in older patients with major depressive disorder (MDD) need to be confirmed before they can guide treatment. Objective To create decision trees for early identification of older patients with MDD who are unlikely to respond to 12 weeks of antidepressant treatment, we analysed data from 454 older participants treated with venlafaxine XR (150–300 mg/day) for up to 12 weeks in the Incomplete Response in Late-Life Depression: Getting to Remission study. Methods We selected the earliest decision point when we could detect participants who had not yet responded (defined as >50% symptom improvement) but would do so after 12 weeks of treatment. Using receiver operating characteristic models, we created two decision trees to minimise either false identification of future responders (false positives) or false identification of future non-responders (false negatives). These decision trees integrated baseline characteristics and treatment response at the early decision point as predictors. Finding We selected week 4 as the optimal early decision point. Both decision trees shared minimal symptom reduction at week 4, longer episode duration and not having responded to an antidepressant previously as predictors of non-response. Test negative predictive values of the leftmost terminal node of the two trees were 77.4% and 76.6%, respectively. Conclusion Our decision trees have the potential to guide treatment in older patients with MDD but they require to be validated in other larger samples. Clinical implications Once confirmed, our findings may be used to guide changes in antidepressant treatment in older patients with poor early response. Data are available on reasonable request.

中文翻译：

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文拉法辛 XR 治疗老年重度抑郁症患者：何时改变治疗的决策树

背景 老年重度抑郁症 (MDD) 患者抗抑郁反应的预测因素需要得到确认，然后才能指导治疗。目的 为了创建决策树，以便早期识别不太可能对 12 周抗抑郁药物治疗产生反应的老年 MDD 患者，我们分析了 454 名接受文拉法辛 XR（150-300 mg/天）治疗长达 12 周的老年参与者的数据。晚年抑郁症的不完全反应：缓解研究。方法 我们选择了最早的决策点，即当我们能够检测到尚未做出反应（定义为> 50% 症状改善）但在治疗 12 周后会做出反应的参与者时。使用接收者操作特征模型，我们创建了两个决策树，以最大限度地减少未来响应者的错误识别（误报）或未来无响应者的错误识别（漏报）。这些决策树整合了早期决策点的基线特征和治疗反应作为预测因子。发现 我们选择第 4 周作为最佳早期决策点。两个决策树在第 4 周时的症状减轻程度最低，发作持续时间较长，并且之前对抗抑郁药没有反应，这些都是无反应的预测因素。两棵树最左边终端节点的测试阴性预测值分别为77.4%和76.6%。结论 我们的决策树有潜力指导老年 MDD 患者的治疗，但需要在其他更大的样本中进行验证。临床意义 一旦得到证实，我们的研究结果可用于指导早期反应较差的老年患者抗抑郁治疗的改变。可根据合理要求提供数据。