Influence of obesity on the association between antinuclear antibodies and cognitive impairment: A nationwide population-based cross-sectional study.

Cognitive impairment is a significant health concern among older adults. Most cognitive disorders are challenging to treat due to their complex and often unclear causes. Emerging evidence suggests a possible association between antinuclear antibodies (ANA) and cognitive impairment, although this relationship remains debated. Obesity is associated with lower ANA titers and may influence ANA production. Therefore, the present study seeks to elucidate the impact of obesity status on the relationship between ANA and cognitive impairment. Data from the National Health and Nutrition Examination Survey (1999-2002), including 1050 participants, were analyzed. Multivariate logistic regression and interaction tests assessed the differences in ANA and cognitive impairment risk among participants within each subgroup. In this cross-sectional study, the association between ANA and cognitive impairment incidence varied between the obesity and nonobesity groups (OR: 0.24, 95% Cl: 0.07-0.82 vs OR: 2.15, 95% Cl: 1.19-3.89). A significant interaction was observed between ANA and obesity concerning cognitive impairment risk (P <.001). Obesity modifies the relationship between ANA and cognitive impairment and underscores the importance of metabolic context in interpreting immune-related biomarkers in cognitive impairment.