Handgrip strength (HGS) is a simple, noninvasive measure that may help with the early detection and risk assessment of cognitive decline in middle-aged and older adults. This study aimed to explore the relationship between both absolute and relative measures of HGS and cognitive impairment in a nationally representative sample of Mexican adults aged 55 and older.

This secondary cross-sectional study included 1870 participants (58.4% women; mean age = 68.1 ± 8.7 years) from the Mexican Cognitive Aging Study (Mex-Cog). Data from individuals aged ≥ 55 years included socioeconomic, lifestyle, anthropometric, and biomarker information. HGS was assessed using a dynamometer in absolute values (kg) and relative indices (HGS/height, HGS/height², HGS/weight, and HGS/BMI). Quartiles (Q) were created, with Q4 representing the highest performance. Cognitive impairment was defined as an MMSE score of < 24 points. Associations were examined using sex-stratified binary logistic regression adjusted for age, education level, and population density.

Women in the lowest quartile of absolute handgrip strength had significantly higher odds of cognitive impairment than those in the highest quartile (odds ratio [OR] = 2.24, 95% CI 1.04–4.80, p = 0.039). In men, significant associations were found for the second quartile of HGS normalised by height and height². Overall, absolute HGS and HGS/height² showed the strongest and most consistent significant association with cognitive impairment.

Lower absolute and relative HGS values were strongly associated with a higher likelihood of cognitive impairment in Mexican adults. Due to its low cost, accessibility, and reproducibility, HGS may represent a practical biomarker for the early detection and tracking of cognitive decline, particularly in low-resource settings.