背景:含组氨酸的二肽(肌肽,Anseri,β-丙氨酸和其他)在人体肌肉组织和大脑等其他器官中发现。啮齿动物和人类中的数据表明外源性肌肽的施用改善了认知表现。然而,RCT结果各不相同。
目的:对补充含组氨酸二肽(HCD)对人类认知能力的随机对照试验(RCT)进行系统评价和荟萃分析,以评估其作为认知稳定剂的效用。
方法:OVIDMedline,Medline,EBM评论,Embase,从1965年1月1日至2022年1月6日,对所有HCD的RCT进行了护理和相关健康文献数据库的累积索引。
方法:筛选2653篇摘要,确定94篇被评估为合格的全文文章。对10篇报告使用HCD补充剂的文章进行了荟萃分析。
方法:使用DerSimonian-Laird方法应用了随机效应模型。HCD治疗显着提高了韦氏记忆量表(WMS)-2延迟召回(加权平均差(WMD)(95%CI(CI))=1.5(0.6,2.5),P<.01)。HCD治疗对阿尔茨海默病评估量表-认知(WMD(95%CI)=-0.2(-1.1,0.7),P=.65,I2=0%),简易精神状态检查(WMD(95%CI)=0.7(-0.2,1.5),P=.14,I2=42%),韦氏成人智力量表(WAIS)数字跨度向后(WMD(95%CI)=0.1(-0.3,0.5),P=.51,I2=0%),WAIS数字跨度正向(WMD(95%CI)=0.0(-0.3,0.4),P=.85,I2=33%)和WMS-1立即召回(大规模杀伤性武器(95%CI)=.7(-2,1.5),P=.11,I2=0%)。在对无轻度认知障碍(MCI)的患者进行的亚组荟萃分析中,对延迟回忆的影响仍然存在。在那些没有MCI的人中,研究中的平均年龄超过65岁。
结论:HCD,补充提高了延迟召回考试的分数,一种神经心理学测试在阿尔茨海默病早期受到影响。需要对早期认知障碍患者进行进一步的研究,随访时间更长,肌肽剂量标准化以描述真实效果。
背景:PROSPERO注册号。CRD42017075354。
BACKGROUND: Histidine-containing dipeptides (carnosine, anserine, beta-alanine and others) are found in human muscle tissue and other organs like the brain. Data in rodents and humans indicate that administration of exogenous carnosine improved cognitive performance. However, RCTs results vary.
OBJECTIVE: To perform a systematic
review and meta-analysis of randomized controlled trials (RCTs) of histidine-containing dipeptide (HCD) supplementation on cognitive performance in humans to assess its utility as a cognitive stabiliser.
METHODS: OVID Medline, Medline, EBM Reviews, Embase, and Cumulative Index to Nursing and Allied Health Literature databases from 1/1/1965 to 1/6/2022 for all RCT of HCDs were searched.
METHODS: 2653 abstracts were screened, identifying 94 full-text articles which were assessed for eligibility. Ten articles reporting the use of HCD supplementation were meta-analysed.
METHODS: The random effects model has been applied using the DerSimonian-Laird method. HCD treatment significantly increased performance on Wechsler Memory Scale (WMS) -2 Delayed recall (Weighted mean difference (WMD) (95% CI (CI)) = 1.5 (0.6, 2.5), P < .01). Treatment with HCDs had no effect on Alzheimer\'s Disease Assessment Scale-Cognitive (WMD (95% CI) = -0.2 (-1.1, 0.7), P = .65, I2 = 0%), Mini-Mental State Examination (WMD (95% CI) = 0.7 (-0.2, 1.5), P = .14, I2 = 42%), The Wechsler Adult Intelligence Scale (WAIS) Digit span Backward (WMD (95% CI) = 0.1 (-0.3, 0.5), P = .51, I2 = 0%), WAIS digit span Forward (WMD (95% CI) = 0.0 (-0.3, 0.4), P = .85, I2 = 33%) and the WMS-1 Immediate recall (WMD (95% CI) = .7 (-.2, 1.5), P = .11, I2 = 0%). The effect on delayed recall remained in subgroup meta-analysis performed on studies of patients without mild cognitive impairment (MCI), and in those without MCI where average age in the study was above 65.
CONCLUSIONS: HCD, supplementation improved scores on the Delayed recall examination, a neuropsychological test affected early in Alzheimer\'s disease. Further studies are needed in people with early cognitive impairment with longer follow-up duration and standardization of carnosine doses to delineate the true effect.
BACKGROUND: PROSPERO registration no. CRD42017075354.