Oken B S, Storzbach D M, Kaye J A
Department of Neurology, Oregon Health Sciences University, Portland 97201, USA.
Arch Neurol. 1998 Nov;55(11):1409-15. doi: 10.1001/archneur.55.11.1409.
To determine the effect of treatment with Ginkgo biloba extract on objective measures of cognitive function in patients with Alzheimer disease (AD) based on formal review of the current literature.
An attempt was made to identify all English and non-English-language articles in which G. biloba extract was given to subjects with dementia or cognitive impairment. Inclusion criteria for the meta-analysis were (1) sufficiently characterized patients such that it was clearly stated there was a diagnosis of AD by either Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition, or National Institute of Neurological Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, or there was enough clinical detail to determine this by our review; (2) clearly stated study exclusion criteria, ie, those studies that did not have stated exclusions for depression, other neurologic disease, and central nervous system-active medications were excluded; (3) use of standardized ginkgo extract in any stated dose; (4) randomized, placebo-controlled and double-blind study design; (5) at least 1 outcome measure was an objective assessment of cognitive function; and (6) sufficient statistical information to allow for meta-analysis.
Of more than 50 articles identified, the overwhelming majority did not meet inclusion criteria, primarily because of lack of clear diagnoses of dementia and AD. Only 4 studies met all inclusion criteria. In total there were 212 subjects in each of the placebo and ginkgo treatment groups. Overall there was a significant effect size of 0.40 (P<.0001). This modest effect size translated into a 3% difference in the Alzheimer Disease Assessment Scale-cognitive subtest.
Based on a quantitative analysis of the literature there is a small but significant effect of 3- to 6-month treatment with 120 to 240 mg of G. biloba extract on objective measures of cognitive function in AD. The drug has not had significant adverse effects in formal clinical trials but there are 2 case reports of bleeding complications. In AD, there are limited and inconsistent data that preclude determining if there are effects on noncognitive behavioral and functional measures as well as on clinician's global rating scales. Further research in the area will need to determine if there are functional improvements and to determine the best dosage. Additional research will be needed to define which ingredients in the ginkgo extract are producing its effect in individuals with AD.
基于对当前文献的正式综述，确定银杏叶提取物治疗对阿尔茨海默病（AD）患者认知功能客观指标的影响。
尝试识别所有给予银杏叶提取物治疗痴呆或认知障碍受试者的英文和非英文文章。荟萃分析的纳入标准为：（1）对患者有充分的特征描述，明确指出根据《精神疾病诊断与统计手册》第三版修订本或美国国立神经疾病与中风研究所 - 阿尔茨海默病及相关疾病协会标准诊断为AD，或通过我们的综述有足够的临床细节来确定这一点；（2）明确说明研究排除标准，即排除那些未说明排除抑郁症、其他神经系统疾病和中枢神经系统活性药物的研究；（3）使用任何规定剂量的标准化银杏提取物；（4）随机、安慰剂对照和双盲研究设计；（5）至少有1项结局指标是对认知功能的客观评估；（6）有足够的统计信息以进行荟萃分析。
在识别出的50多篇文章中，绝大多数不符合纳入标准，主要原因是缺乏对痴呆和AD的明确诊断。只有4项研究符合所有纳入标准。安慰剂组和银杏治疗组每组共有212名受试者。总体而言，效应量显著为0.40（P <.0001）。这个适度的效应量转化为阿尔茨海默病评估量表 - 认知子测试中3%的差异。
基于文献的定量分析，120至240毫克银杏叶提取物进行3至6个月的治疗对AD患者认知功能的客观指标有小但显著的影响。该药物在正式临床试验中未产生显著不良反应，但有2例出血并发症的病例报告。在AD中，数据有限且不一致，无法确定其对非认知行为和功能指标以及临床医生整体评定量表是否有影响。该领域的进一步研究需要确定是否有功能改善以及确定最佳剂量。还需要进行额外的研究来确定银杏提取物中的哪些成分对AD患者产生作用。
