Prior research has consistently shown an association between muscle strength and various metabolic diseases. However, the relationship between muscle strength and cognitive impairment remains elusive.
Using data from the 2011–2014 National Health and Nutrition Examination Survey (NHANES), we investigated the association between muscle strength and cognitive impairment. We used multivariate logistic regression, restricted cubic spline regression (RCS), and threshold effects to investigate the impact of muscle strength on cognitive function. In addition, we analyzed the correlation between muscle strength and cognitive impairment in subgroups of age, gender, race, education, smoking status, drinking status, hypertension, diabetes, and heart disease.
2124 participants were ultimately included for further analysis. Multivariate logistic regression, trend testing, and RCS analysis showed a non-linear negative correlation between muscle strength and cognitive impairment. Threshold effect analysis suggests that when muscle strength reaches a certain value, this relationship undergoes significant changes. In the three cognitive function scoring tests, interaction was only observed in the racial subgroup.
This study suggests a negative correlation between muscle strength and cognitive function, which may have a threshold effect. Further longitudinal studies are needed to elucidate its potential mechanisms.