Phenomenology of Atypical Anxiety Disorders in Parkinson's Disease: A Systematic Review

Objective: Anxiety is a prominent concern in Parkinson's disease (PD) that negatively impacts quality of life, increases functional disability, and compli-cates clinical management. Atypical presentations of anxiety are under -recog-nized and inadequately treated in patients with PD, compromising global PD care. Methods: This systematic review focuses on the prevalence, symptomol-ogy and clinical correlates of atypical presentations of PD-related anxiety fol-lowing PRISMA guidelines. Results: Of the 60 studies meeting inclusion criteria, 14 focused on 'Anxiety Not Otherwise Specified (NOS)' or equivalent, 31 reported on fluctuating anxiety symptoms, and 22 reported on 'Fear of Fall-ing (FOF)'. Anxiety NOS accounted for a weighted mean prevalence of 14.9%, fluctuating anxiety for 34.19%, and FOF for 51.5%. These latter two exceeded the average reported overall prevalence rate of 31% for anxiety disorders in PD. We identified a diverse array of anxiety symptoms related to motor and non -motor symptoms of PD, to complications of PD medication (such as " on" and " off" fluctuations, or both), and, to a lesser extent, to cognitive symptoms. Conclusion: Atypical anxiety is common, clinically relevant, and heteroge-neous in nature. A better understanding of the phenomenology, clinical course, and pathophysiology of varied forms of atypical anxiety in PD is needed to improve recognition, advance therapeutic development and ultimately opti-mize quality of life in PD. (Am J Geriatr Psychiatry 2022; 30:1026-1050)