• affective disorders
• Bipolar disorder
• movement disorders
• Parkinson’s disease

Background: Psychiatric comorbidity is well known in Parkinson Disease (PD), however only apathy, depression and anxiety have been systematically studied. Lifetime prevalence and clinical implications of comorbid of PD and Bipolar Spectrum Disorders are understudied. Aims: The major aims of the present study is the evaluation of psychiatric co-morbidity in a cohort of PD patients and to explore the clinical correlates of PD associated with Bipolar Spectrum Disorders. Methods: 77 PD patients have been screened for psychiatric comorbidities, cognitive profile, motor and non-motor symptoms using validated rating scales. The sample has been divided into three groups: PD-patients with bipolar disorders (BD) comorbidity (N=27), PD-patients with others psychiatric comorbidities (N=27), PD-patients without psychiatric comorbidities (N=23). Clinical aspects of PD were compared among the three groups at univariate and multivariate level. Results: In comparison with the other two groups of PD patients with and without other psychiatric comorbidity, PD patients with BD are younger, showed an an earlier age at onset of PD, reported more involuntary movements, as well as higher rate of first degree familiarity for BD and of ICDs and compulsive behaviors. Moreover BD diagnosis precedes the diagnosis of PD. Conclusion: Bipolar disorder is associated with early onset of PD, involuntary movements and lifetime ICDs. The bipolar diathesis probably identify a particular subtype of PD, that deserves further investigation. Looking at the evolution of this specific subtype could also shed light over some clinical features of bipolar disorder associated with neurodegenerative conditions.