Diagnostic status moderates the association between verbal memory and left hippocampal volume in older adults with generalised anxiety disorder and healthy controls.

INTRODUCTION

Generalised anxiety disorder (GAD) in older adults involves excessive worry and cognitive challenges. Verbal memory impairments is associated to hippocampal dysfunction, with cortisol and brain-derived neurotrophic factor (BDNF) being important in hippocampal integrity. Research on hippocampal volume and verbal memory in older adults with GAD is limited, with mixed findings. This study investigates verbal memory in older adults with GAD versus healthy controls, and relations with hippocampal volumes.

METHODS

Participants included 49 adults with GAD (Mage = 65.82, SD = 3.94) and 49 controls (Mage = 67.73, SD = 4.11). Verbal memory was assessed using the California Verbal Learning Test Long Delay Free Recall, hippocampal volumes via MRI, BDNF from serum, and cortisol via saliva. We fitted a Bayesian multivariate linear regression with bilateral hippocampal volume as outcome measure, and predictors: age, gender, education, intracranial volume, IQ, BDNF, cortisol, SSRI use, CVLT Long Delay Free Recall (LD FR), CVLT Learning, and diagnostic status*CVLT LD FR interaction.

RESULTS

A credible interaction showed better verbal memory associated to larger hippocampal volume in controls, but this relationship was attenuated in GAD. BDNF and cortisol were not credibly associated with hippocampal volume.

CONCLUSION

Diagnostic status moderates verbal memory and hippocampal volume relations, suggesting a distinct neurocognitive profile in older adults with GAD compared to healthy controls.