Cognitive intervention includes cognitive stimulation, cognitive training, and cognitive rehabilitation. This systematic review was performed to re-assess the efficacy of cognitive intervention for the patients with Alzheimer’s disease (AD). Twenty studies (2012 participants) were eventually included. For global cognitive function, the combined mean difference (MD) in eight studies was 1.67 (95% Confidence Interval: 0.45, 2.89, p = 0.007; Q = 33.28, df = 8, p < 0.0001, τ² = 2.17, I² = 76%) for the short term. The pooled standardized mean difference (SMD) of six RCTs was 1.61 (95% Confidence Interval: 0.65, 2.56, p = 0.0009; Q = 127.66, df = 6, p < 0.00001, τ² = 1.56, I² = 95%) for the medium term. The pooled SMD of seven studies was 0.79 (95% Confidence Interval: 0.33, 1.25, p = 0.0008; Q = 35.10, df = 7, p < 0.0001, τ² = 0.33, I² = 80%) for the long term. For depression, the pooled SMD of two trials was -0.48 (95% Confidence Interval: -0.71, -0.24; p < 0.0001, I² = 4%) for the short term. Cognitive training may show obvious improvements in global cognitive function whether after short, medium, or long-term interventions and in depression after short term intervention. However, the positive effect of the intervention on general cognitive function or depression did not seem to persist after intervention ended. There is still a lack of reliable and consistent conclusions relevant to the effect of cognitive stimulation and cognitive rehabilitation on observed outcomes, cognitive training for memory or other non-cognitive outcomes. PROSPERO registration number: CRD42019121768.

认知干预包括认知刺激、认知训练和认知康复。这项系统评价旨在重新评估认知干预对阿尔茨海默病 (AD) 患者的疗效。最终纳入了 20 项研究（2012 名参与者）。对于整体认知功能，八项研究的综合平均差 (MD) 为 1.67（95% 置信区间：0.45、2.89、p  = 0.007；Q  = 33.28、df = 8、p  < 0.0001、τ ²  = 2.17、I ²  = 76%) 短期内。六项 RCT 的汇总标准化平均差 (SMD) 为 1.61（95% 置信区间： 0.65、2.56、 p  = 0.0009；Q  = 127.66、df = 6、 中期p  < 0.00001, τ ²  = 1.56, I ^{2 = 95%)。}七项研究的汇总 SMD 为 0.79（95% 置信区间： 0.33、1.25、 p  = 0.0008；Q  = 35.10、df = 7、p  < 0.0001、τ ²  = 0.33、I ²  = 80%）。对于抑郁症，两项试验的汇总 SMD 为 -0.48（95% 置信区间：-0.71，-0.24；p  < 0.0001，I ² = 4%) 短期。无论是在短期、中期或长期干预后，还是在短期干预后抑郁症中，认知训练都可能显示出明显的整体认知功能改善。然而，干预对一般认知功能或抑郁症的积极影响似乎在干预结束后并未持续存在。关于认知刺激和认知康复对观察结果、记忆认知训练或其他非认知结果的影响，仍然缺乏可靠和一致的结论。PROSPERO 注册号：CRD42019121768。