AUTHOR=Wang Rong , Zhang Hanyue , Li Hongjuan , Ren Hong , Sun Tingting , Xu Liya , Liu Yang , Hou Xiao 

TITLE=The influence of exercise interventions on cognitive functions in patients with amnestic mild cognitive impairment: A systematic review and meta-analysis

JOURNAL=Frontiers in Public Health

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2022.1046841

DOI=10.3389/fpubh.2022.1046841

ISSN=2296-2565

ABSTRACT=Introduction: Among the mixed samples of amnestic mild cognitive impairment (aMCI) and non-aMCI (naMCI), exercise interventions are effective for patients with MCI to improve cognitive functions. However, the influence of exercise interventions on patients with aMCI is unclear.
Objective: The systematic review and meta-analysis intends to evaluate the influence of exercise interventions on cognitive functions in aMCI patients.
Methods: Four literature databases (PubMed, Web of Science, EBSCO, and Cochrane Library) and three Chinese databases (China National Knowledge Infrastructure, Wanfang, and China Science and Technology Journal Database) were searched from their inception to August 31, 2022. Based on the preliminary search of seven databases and their cited references, a total of 2290 records were identified. Finally, ten studies with a total of 28 data points involving 575 participants with aMCI were included in this meta-analysis. 
Data Synthesis: The results showed that exercise interventions had no significant effects on improving several specific domains of cognitive functions including working memory (WMD = -0.05; 95% CI = -0.74 to 0.63; p = 0.88; I2 = 78%) and attention (SMD = 0.20; 95% CI = -0.31 to 0.72; p= 0.44; I2 = 60%). Additionally, exercise interventions had a significant effect on global cognitive function (SMD = 0.70; 95% CI = 0.50 to 0.90; p ＜0.00001; I2 = 29%) and some specific cognitive domains including immediate recall (SMD = 0.55; 95% CI = 0.28 to 0.81; p＜0.0001; I2 = 0%), delayed recall (SMD = 0.66; 95% CI = 0.45 to 0.87; p＜0.00001; I2 = 37%), and executive function (SMD = -0.38; 95% CI = -0.60 to -0.16; p= 0.0006; I2 = 4%). Furthermore, subgroup analysis based on the intervention forms indicated that multi-component interventions (SMD = 0.44; 95% CI = 0.11 to 0.77; p = 0.009; I2 = 0%) were less effective than the single-component intervention (SMD = 0.85; 95% CI = 0.60 to 1.10; p＜0.00001; I2 = 10%) in terms of boosting global cognitive function.
Conclusions: This meta-analysis suggests that the exercise can help patients with aMCI improve global cognitive function and several specific cognitive domains such as immediate recall, delayed recall, and executive function.