Recent reviews have explored Parkinson's Disease (PD) through psychiatric lenses. However, emerging literature allows to go beyond psychosis, depression, and impulse control disorders. Two key emerging themes are prominent: firstly, studies accrued in the past 13 years challenge prevailing views by demonstrating Somatic Symptom Disorders/Somatoform Disorders (SSD-SD) significantly participate in the PD phenotype, with relevant treatment implications. Secondly, epidemiological data reveal a link between Bipolar Spectrum Disorders (BSD) and PD, prompting a reconsideration of Impulse Control Disorder/Hedonistic Homeostatic Dysregulation (ICD/HHD) in PD. Furthermore, behaviors akin to BSD symptoms during manic states are observed in PD, suggesting shared neurobiological underpinnings. Our proposed review tackles these themes, dissecting the impact of SSD-SD on PD and highlighting the BSD-PD convergence. This approach has implications for tailored psychotherapeutic techniques targeting psychosomatic and functional neurologic disorders within the context of PD care. Moreover, recognizing the blurred lines between neurology and psychiatry in PD underscores the importance of a holistic, interdisciplinary approach. As these findings challenge established assumptions and offer new avenues for patient care, we must promote our understanding of PD's intricate neuropsychiatric dimensions.
Keywords: Bipolar Spectrum Disorders; Neuropsychiatric Disorders; Parkinson’s Disease; Somatic Symptom Disorders.
© 2025 The Authors. Published by Elsevier Ltd.