scholarly journals Serum Ghrelin in Mild Cognitive Impairment and Alzheimer's Disease A Systematic Review and Meta-analysis

2021 ◽  
Author(s):  
Xiaodong Chen ◽  
Yunfeng Luo
Keyword(s):  
Systematic Review ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Meta Analysis ◽  
Serum Levels ◽  
Cochrane Library ◽  
Significant Heterogeneity ◽  
Serum Ghrelin

Abstract Background Serum ghrelin levels have been reported to be altered in Alzheimer’s disease (AD) patients and individuals with Mild cognitive impairment (MCI). However, whether serum ghrelin can be used as a biomarker of AD is inconsistent and conflicting. Methods We carried out a systematic review and meta-analysis to examine the serum levels of ghrelin and acylated ghrelin (AG) in patients with AD or MCI, in comparison with normal controls (NC). We searched PubMed, The Cochrane Library, Web of Science and Chinese National Knowledge Infrastructure (CNKI) from 1999 to March 2021. Results 10 relevant studies were included for this study. 8 studies reported serum levels of ghrelin (417 AD or MCI patients and 382 controls) and 5 studies reported serum levels of AG (142 AD or MCI patients and 152 controls). We found that AD and MCI patients had a tendency toward a decrease in the serum levels of ghrelin (SMD=-1.04; 95%CI (-2.30, 0.23); P = 0.11; significant heterogeneity: I2 = 98%), but no statistical significance was found. AG levels in the serum level of AD and MCI patients were significantly higher than NC subjects (SMD = 0.99; 95%CI (0.21, 1.77); P = 0.01; significant heterogeneity: I2 = 87%). Conclusion This meta-analysis suggested that AG may be a potential MCI or early AD biomarker and confirmed previous findings that ghrelin became desensitized in AD patients. This meta-analysis was limited to small sample sizes and lacked of stratifying the level of heterogeneity in AD and MCI patients. More and large sample, multi-center case-control studies on the relationship between serum AG and AD or MCI patients are still needed in the future.

scholarly journals Alzheimer’s Disease, Mild Cognitive Impairment and Mediterranean Diet. A Systematic Review and Dose-Response Meta-Analysis

2021 ◽  
Vol 10 (20) ◽  
pp. 4642
Author(s):  
Natalia García-Casares ◽  
Paloma Gallego Fuentes ◽  
Miguel Ángel Barbancho ◽  
Rosa López-Gigosos ◽  
Antonio García-Rodríguez ◽  
...  
Keyword(s):  
Systematic Review ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Mediterranean Diet ◽  
Lower Risk ◽  
Meta Analysis ◽  
Cochrane Library ◽  
Qualitative Synthesis

Alzheimer’s Disease (AD) is a pathology with increasing prevalence in the context of a more long-lived society and it is the first cause of dementia in western countries. It is important to investigate factors that can be protective and may influence its development, in order to act on them trying to reduce AD incidence and its progression. The aim of this study was to conduct a systematic review and meta-analysis to determine the effects of a higher adherence to Mediterranean diet (MD) on Mild Cognitive Impairment (MCI) and AD. A literature search in PubMed, The Cochrane Library Plus and Scopus was conducted, selecting articles that analyzed associations between MD adherence and AD biomarkers (Volumetry assessed by MRI and betamiloide and Tau deposits by PET); cognitive performance in patients at risk or presenting MCI and AD; and incidence or progression from MCI to AD. Out of the 589 studies screened, 22 studies met eligibility criteria for the systematic review and qualitative synthesis. Finally, 11 studies were included in the meta-analysis (12,458 participants). Higher adherence to MD was associated with a significantly lower risk of MCI (RR = 0.91, 95%CI = 0.85–0.97) and lower risk of AD (RR = 0.89, 95% CI = 0.84–0.93). Our results enhance the importance of taking health-promoting lifestyle measures like following Mediterranean dietary patterns in order to reduce AD risk.

scholarly journals Meta-Analysis of Neurochemical Changes Estimated via Magnetic Resonance Spectroscopy in Mild Cognitive Impairment and Alzheimer's Disease

2021 ◽  
Vol 13 ◽  
Author(s):  
Huanhuan Liu ◽  
Dandan Zhang ◽  
Huawei Lin ◽  
Qi Zhang ◽  
Ling Zheng ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Meta Analysis ◽  
Cochrane Library ◽  
Resonance Spectroscopy ◽  
Neurochemical Changes

The changes of neurochemicals in mild cognitive impairment (MCI) and Alzheimer's disease (AD) patients has been observed via magnetic resonance spectroscopy in several studies. However, whether it exists the consistent pattern of changes of neurochemicals in the encephalic region during the progression of MCI to AD were still not clear. The study performed meta-analysis to investigate the patterns of neurochemical changes in the encephalic region in the progress of AD. We searched the PubMed, Embase, Cochrane Library, and Web of Science databases, and finally included 63 studies comprising 1,086 MCI patients, 1,256 AD patients, and 1,907 healthy controls. It showed that during the progression from MCI to AD, N-acetyl aspartate (NAA) decreased continuously in the posterior cingulate (PC) (SMD: −0.42 [95% CI: −0.62 to −0.21], z = −3.89, P < 0.05), NAA/Cr (creatine) was consistently reduced in PC (SMD: −0.58 [95% CI: −0.86 to −0.30], z = −4.06, P < 0.05) and hippocampus (SMD: −0.65 [95% CI: −1.11 to −0.12], z = −2.44, P < 0.05), while myo-inositol (mI) (SMD: 0.44 [95% CI: 0.26–0.61], z = 4.97, P < 0.05) and mI/Cr (SMD: 0.43 [95% CI: 0.17–0.68], z = 3.30, P < 0.05) were raised in PC. Furthermore, these results were further verified by a sustained decrease in the NAA/mI of PC (SMD: −0.94 [95% CI: −1.24 to −0.65], z = −6.26, P < 0.05). Therefore, the levels of NAA and mI were associated with the cognitive decline and might be used as potentially biomarkers to predict the possible progression from MCI to AD.Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42020200308.

Sign in / Sign up

Export Citation Format

Share Document