A systematic review and meta‐analysis of the prevalence and correlation of mild cognitive impairment in sarcopenia

Abstract

Sarcopenia is a progressive skeletal muscle disorder involving the loss of muscle mass and function, associated with an increased risk of disability and frailty. Though its prevalence in dementia has been studied, its occurrence in mild cognitive impairment (MCI) has not been well established. As MCI is often a prelude to dementia, our study aims to investigate the prevalence of MCI among individuals with sarcopenia and to also ascertain whether sarcopenia is independently associated with MCI. The Cochrane Library, PubMed, Ovid, Embase and Web of Science were systematically searched for articles on MCI and/or sarcopenia published from inception to 1 February 2022. We reviewed the available literature on the number of individuals with MCI and/or sarcopenia and calculated odds ratios (ORs) of sarcopenia in MCI and MCI in sarcopenia, respectively. Statistical analyses were performed using the meta package in Stata, Version 12.0. A total of 13 studies and 27 428 patients were included in our analysis. The pooled prevalence of MCI in participants with sarcopenia was 20.5% (95% confidence interval [CI]: 0.140–0.269) in a total sample of 2923 cases with a high level of heterogeneity (P < 0.001; I2 = 95.4%). The overall prevalence of sarcopenia with MCI was 9.1% (95% CI: 0.047–0.134, P < 0.001; I2 = 93.0%). For overall ORs, there were 23 364 subjects with a mean age of 73 years; the overall adjusted OR between MCI and sarcopenia was 1.46 (95% CI: 1.31–1.62). Slight heterogeneity in both adjusted ORs (P = 0.46; I2 = 0%) was noted across the studies. The prevalence of MCI is relatively high in patients with sarcopenia, and sarcopenia may be a risk factor for MCI.

The prevalence and factors associated with sarcopenia in Thai older adults: A systematic review and meta-analysis

“…Consequently, older adults with MCI are at risk of developing sarcopenia due to decreased physical activity and malnutrition. These findings align with previous research indicating an association between MCI and sarcopenia [ 87 , 91 ]. The prevalence of sarcopenia was found to be 5.5 times higher in older adults with MCI compared to those with normal cognitive function [ 87 ].…”

“…Older adults with MCI often experience reduced physical activity levels [ 88 , 89 ], which is linked to decreased grip strength and slower walking speed [ 90 ]. Additionally, individuals with impaired brain function may suffer from anorexia, resulting in reduced food intake and malnutrition [ 91 ]. Consequently, older adults with MCI are at risk of developing sarcopenia due to decreased physical activity and malnutrition.…”

Cognition as mediator of pulmonary function and risk of sarcopenia among older adults

“…Pulmonary function decline may decrease cognitive performance via hypoxia, decreased neurotransmitter function, increased systemic inflammatory processes, or a combination of various factors [9,10]. Although numerous research have examined that sarcopenia may be a potential contributing factor to cognitive impairment [34,35], our findings indicate a positive correlation between diminished cognitive abilities and increased susceptibility to sarcopenia. Likewise, a longitudinal study also found that any cognitive impairment predicted decreased handgrip strength [36].…”

Causal Associations between Sarcopenia Traits and Cognitive Impairment: A Mendelian Randomization Study

“…Aging is a challenging issue that modern society have to confront, and plays an important role in both sarcopenia and cognitive impairment. Previous evidences demonstrated the association between these two conditions, populations with sarcopenia have a higher risk of cognitive impairment 29 . In addition, this correlation is independent of factors such as gender, region, and race [30][31][32] .…”