Serum Albumin/Globulin Ratio and Cognitive Function in Americans: A Linear Association.

BACKGROUND: Nutritional status and chronic inflammation play crucial roles in cognitive impairment. The albumin-globulin ratio (AGR) serves as a biomarker for assessing nutrition and inflammation; however, its relationship with cognitive function remains unclear. The objective of this study is to investigate the correlation between them. METHODS: The present study utilized data obtained from the National Health and Nutrition Examination Surveys conducted during the years 2001-2002 and 2011-2014. The relationships between the AGR and cognitive impairment were assessed through the application of weighted logistic regression analysis, smoothed fitted curves, the investigation of threshold effects, and the execution of subgroup analysis. In this study, participants with lower AGR values had a greater incidence of cognitive impairment. RESULTS: The results of the logistical regression model, following adjustments for all potential influencing factors, demonstrated that the AGR may be associated with an increased incidence of cognitive impairment (OR: 0.550, 95% CI: 0.359, 0.843). This finding indicates that for each unit increase in the AGR within the fourth quartile, the prevalence of cognitive impairment decreased by 45%. Smoothed fitted curves and threshold effects demonstrated a linear relationship between the AGR and cognitive impairment (OR: 0.448, 95% CI: 0.312, 0.642). Subgroup analysis revealed that the association between the AGR and cognitive impairment was not influenced by factors such as gender, education, or hyperlipidemia. CONCLUSIONS: Having a lower AGR may be linked to a higher risk of cognitive impairment.