Mengzhao Cui, Siwen Zhang, Yujia Liu, Xiaokun Gang,* and Guixia Wang*

Front Aging Neurosci. 2021; 13: 625551. Published online 2021 Feb 4.


Purpose: Loss of grip strength and cognitive impairment are prevalent in the elderly, and they may share the pathogenesis in common. Several original studies have investigated the association between them, but the results remained controversial. In this systematic review and meta-analysis, we aimed to quantitatively determine the relationship between baseline grip strength and the risk of cognitive impairment and provide evidence for clinical work.

Methods: We performed a systematic review using PubMed, EMBASE, Cochrane, and Web of Science up to March 23, 2020, and focused on the association between baseline grip strength and onset of cognitive impairment. Next, we conducted a meta-analysis using a hazard ratio (HR) and 95% confidence interval (CI) as effect measures. Heterogeneity between the studies was examined using I2 and p-value. Sensitivity analyses and subgroup analyses were also performed, and publication bias was assessed by Begg’s and Egger’s tests.

Results: Fifteen studies were included in this systematic review. After sensitivity analyses, poorer grip strength was associated with more risk of cognitive decline and dementia (HR = 1.99, 95%CI: 1.71–2.32; HR = 1.54, 95%CI: 1.32–1.79, respectively). Furthermore, subgroup analysis indicated that people with poorer strength had more risk of Alzheimer’s disease (AD) and non-AD dementia (HR = 1.41, 95%CI: 1.09–1.81; HR = 1.45, 95%CI: 1.10–1.91, respectively).

Conclusions: Lower grip strength is associated with more risk of onset of cognitive decline and dementia despite of subtype of dementia. We should be alert for the individuals with poor grip strength and identify cognitive dysfunction early.


Physical performance gradually declines with aging, and loss of grip strength is also a well-recognized manifestation of age-related motor decline and of geriatric syndromes such as sarcopenia and frailty (Buchman et al., 2007). Measure of grip strength is noninvasive and widely available (Ferlay et al., 2019), therefore grip strength measurement is often applied to reflect upper muscle strength in clinical setting. Being sensitive to age-related changes and changes in biological function, grip strength is not only an indicator of muscle strength but also of biological vitality (MacDonald et al., 2004). Furthermore, cognitive decline and dementia are common outcomes of aging that significantly affect the quality of life of the elderly people. Cognitive decline is frequently regarded as a prodrome to dementia, but exists on a continuum with normal aging (Heward et al., 2018). Individuals with cognitive decline are nevertheless at high risk of developing cognitive impairment and dementia.

It is reported that sarcopenia leads to physical inactivity, and physical decline has been consistently associated with future cognitive decline (Cabett Cipolli et al., 2019). Inflammatory and hormonal pathway and brain atrophy might be the explanation for the association between sarcopenia and cognitive impairment (Iannuzzi-Sucich et al., 2002; Schaap et al., 2006). Besides, frailty is common in the elderly. Frailty was defined as a clinical syndrome in which three or more of the following criteria were present: unintentional weight loss (10 lbs in past year), self-reported exhaustion, weakness (low grip strength), slow walking speed, and low physical activity (Fried et al., 2001). Frailty and AD may share underlying pathogeneses, and the rates of change of frailty and cognition over time are strongly associated with the same brain pathologies, such as the presence of macroinfarcts, Alzheimer’s disease pathology, and nigral neuronal loss (Buchman et al., 2014). Besides, sarcopenia, frailty and cognitive impairment are all correlated to aging, oxidative stress and inflammation and so on. A recent meta-analysis (Peng et al., 2019) indicated that sarcopenia was associated with an increased risk of cognitive impairment independent of study population, the definition of sarcopenia and cognitive impairment, but only cross-sectional studies were included in this analysis, and the association between three components of sarcopenia and cognitive function was not identified. Another systematic review (Zammit et al., 2019) showed that cognitive function and grip strength (as the measure of frailty) declined with aging, but with little to no evidence for longitudinal associations between rates of change of both.

Older individuals with low handgrip strength often show symptoms that can interfere with cognitive and physical performance, such as declines in mobility and balance and impairment in executive function and memory (Firth et al., 2018). Grip strength, as an important component of sarcopenia and frailty, was also reported to be associated with cognitive aging (Zammit et al., 2019), its relation to cognitive impairment is of great interest, therefore, we focused on the longitudinal relationship between baseline grip strength and the risk of cognitive impairment. It’s of great benefit that regarding grip strength as an observational indicator, and discerning cognitive impairment at the early stages. Several studies have reported that poorer grip strength was associated with cognitive decline and onset of dementia (Heward et al., 2018; Jeong and Kim, 2018; Jeong et al., 2018), while some studies found no relationship between grip strength and cognitive dysfunction (Sibbett et al., 2018; Doi et al., 2019). This meta-analysis aimed to investigate the relationship between grip strength and onset of cognitive impairment including cognitive decline and dementia, in order to identify dementia earlier especially in persons who have lower grip strength and promote more appropriate planning for prevention and treatment for dementia.