Distinct and Combined Cognitive Profiles Associated With Depression and Anxiety in Patients With Early Parkinson's Disease.

OBJECTIVE

Cognitive impairment is a major nonmotor manifestation of Parkinson's disease (PD), and mood disorders, including depression and anxiety, are being increasingly recognized as potentially modifiable contributors to cognitive decline. However, studies simultaneously evaluating the individual and combined effects of depression and anxiety on specific cognitive domains in PD remain limited.

METHODS

One hundred forty-nine patients with early- to mid-stage PD were stratified by depression (Beck Depression Inventory≥14) and anxiety (Beck Anxiety Inventory≥8) status. Cognitive performance was evaluated using the Seoul Neuropsychological Screening Battery. Group differences were analyzed using analyses of covariance, adjusting for education, Hoehn and Yahr stage, and Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale motor scores, followed by Bonferroni correction for multiple testing.

RESULTS

After adjustment for covariates, depression was associated with impaired verbal recognition memory (p=0.009), although this association did not survive Bonferroni correction. Conversely, anxiety-related deficits in immediate visual recall (p= 0.006) and inhibitory executive control (p=0.016) remained robustly significant even after rigorous correction. Patients with comorbid depression and anxiety exhibited the most pervasive cognitive impairment, including statistically significant deficits in both visual memory and frontal executive function (all adjusted p<0.05).

CONCLUSION

Depression and anxiety exert distinct yet additive detrimental effects on cognition in patients with early PD. While anxiety and comorbid symptoms show robust associations with visuospatial and executive deficits, the impact of isolated depression appears less statistically stable under conservative thresholds. These findings underscore the importance of early neuropsychiatric screening and targeted intervention, which may be associated with the maintenance of cognitive health in patients with PD.