Non-recognition of depression and other non-motor symptoms in Parkinson’s disease

Background: Depression, anxiety, fatigue and sleep disorders occur commonly in patients with Parkinson's disease (PD). These non-motor symptoms often contribute to the reduction of functional abilities in PD patients. Objective: This study was designed to evaluate the diagnostic accuracy of the treating neurologist for a variety of behavioral symptoms commonly associated with PD. Methods: A prospective evaluation of 101 patients with PD selected in no particular order was conducted. All patients were evaluated with the Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn & Yahr Stage (H/Y), and the Schwab & England Scale (S/E). The patients completed a brief screening questionnaire for depression and anxiety followed by the administration of a battery of standardized tests including the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Fatigue Severity Scale (FSS), and the Pittsburgh Sleep Quality Inventory (PSQI).Results: Standardized testing showed evidence of a problem with depression in 44% of patients, anxiety in 39%, fatigue in 42% and sleep disturbance in 43%. The prevalence of these conditions, identified by the treating neurologist was lower: 21% with depression, 19% with anxiety, 14% with fatigue and 39% with sleep disturbance. The diagnostic accuracy for the treating neurologists was 35% for depression, 42% for anxiety, 25% for fatigue, and 60% for sleep disturbance. Conclusion: This study demonstrates that during routine office visits, neurologists failed to identify the presence of depression, anxiety, and fatigue more than half of the time and failed to recognize sleep disturbance in 40% of patients. Awareness of the likelihood of underrecognition of behavioral symptoms in PD should generate approaches to improve diagnostic accuracy and facilitate timely therapeutic interventions.