[The German Study on the Epidemiology of Parkinson's Disease with Dementia (GEPAD): more than Parkinson]

It is unknown, how frequently Parkinson's disease (PD) is complicated by dementia, depression and other neuropsychiatric conditions. An epidemiologic characterisation of the situation in specialised neurologic settings is lacking. The Geman Study on the Epidemiology of Parkinson's Disease with Dementia (GEPAD) isa national representative epidemiological study of n=1449 PD patients in n=315 office-based neurological settings, designed to estimate the prevalence of dementia, depression and other neuropsychiatric conditions in patients with PD of all stages by using standardized clinical assessments. RESULTS: 28.6% met DSM-IV criteria for dementia. 33.6% met criteria for depression and 61% additionally had other clinically significant psychopathological syndromes. Only 29.4% had no neuropsychiatric conditions. GEPAD reveals for the first time comprehensively that the neuropsychiatric burden of PD patients in all stages and even early stages is considerable, posing challenging questions for research and clinical management