Social phobia in Parkinson's disease: Prevalence and risk factors

Objective: We aimed to investigate the frequency of social phobia in patients with Parkinson's disease (PD). In addition, we explored the relationship between social phobia and the clinical characteristics of PD, and the frequency of comorbid psychiatric disorders in PD patients. Methods: This study included 80 consecutive patients with PD admitted to the Parkinson's disease and Movement Disorders Clinic at the Erenkoy Research and Training Hospital for Neurologic and Psychiatric Disorders, Istanbul, Turkey and used demographic and clinical data. The PD patients were evaluated during the "on state", using the Hoehn and Yahr scale, the Unified Parkinson's Disease Rating Scale, and the Schwab England Activities of Daily Living Scale. Psychiatric evaluations were conducted using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition structured clinical interview, the Liebowitz Social Anxiety Scale (LSAS), and the Hamilton Depression Rating Scale. Results: Social phobia was diagnosed in 42.5% of PD patients. Social phobia was comorbid with depression in 20 patients (58.8%), generalized anxiety disorder in 18 patients (52.9%), and panic disorder in six patients (17.6%). Social phobia was more frequent in males, early-onset PD, patients with a long duration of disease, the presence of postural instability, and with the use of a high Levodopa equivalent daily dose. A logistic regression analysis revealed the predictive factors of social phobia to be the sex of the patient (more frequent in males) and the presence of postural instability. There was a statistically significantly negative correlation between the LSAS score and the age of disease onset (r=-0.503; P=0.002) and a positive correlation between LSAS score and the duration of disease (r=0.374; P=0.023). Conclusion: Social phobia is frequently observed in PD patients. Therefore, the assessment of PD patients should always include psychiatric evaluations, particularly for social phobia. The early detection and treatment of social phobia in PD patients is very important for the quality of life of patients as well as caregivers.