Highlights
- •RYGB is an effective option to ameliorate immediate verbal memory and delayed memory function in the both short and long terms.
- •RYGB may not influence executive function, cognitive speed, and attention in the both short and long terms.
Abstract
Obesity impairs cognition. Bariatric surgery can result in substantial weight loss
in patients with severe obesity; however, the impact of bariatric surgery on cognitive
function remains controversial. To quantify the effect of bariatric surgery on cognition
in patients with severe obesity, we performed a meta-analysis of 20 studies retrieved
from PubMed, Cochrane, and Embase. Of these, 6 cohort studies found that Roux-en-Y
gastric bypass leads to better performance for immediate verbal memory function (standardized
mean difference [SMD] = .56; 95% confidence interval [CI]: .30–.82, P < .0001; I2 = 0%) and delayed memory function (SMD = .64; 95% CI: .38–.90, P < .00001; I2 = 0%) during in the short term. Similarly, positive impacts on immediate verbal memory
function (SMD = .46; 95% CI: .09–.83, P < .00001) and delayed memory function (SMD = .84; 95% CI: .46–1.22, P < .0001) were identified during a long-term follow-up. The Roux-en-Y gastric bypass
group showed no improvements in attention, cognitive speed, and executive function
compared with the control obese group. In 14 longitudinal studies (12 single-arm pre-post
comparison studies and 2 cohort studies whose control group had no follow-up cognitive
data), patients performed better postoperatively than preoperatively in all cognitive
domains during repeated assessments. The analysis for the 20 operative groups showed
that individuals treated with bariatric surgery had higher scores after repeated assessment
of most neuropsychological tests except for animal fluency and letter fluency than
baseline scores. These findings suggest that patients with severe obesity may obtain
immediate verbal and delayed memory function benefits from Roux-en-Y gastric bypass.
Keywords
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Article info
Publication history
Published online: August 03, 2022
Accepted:
July 16,
2022
Received:
March 30,
2022
Footnotes
Chun-mei Li and Jia-run Song contributed equally to this work.
Funding: This work was supported by a grant (to J.D.) from the National Natural Science Foundation of China (No. 31872791) and the Natural Science Foundation of Shandong Province (No. ZR2019MC046) and a grant (to J.-h.Y.) from the National Natural Science Foundation of China (No. 8210033261).
Identification
Copyright
© 2022 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.
