The corticobasal degeneration syndrome overlaps progressive aphasia and frontotemporal dementia

Objective: To provide evidence for the hypothesis that the corticobasal deg eneration syndrome (CBDs) overlaps significantly with primary progressive a phasia and frontotemporal dementia, and that CBDs is part of the Pick compl ex. Background: Corticobasal degeneration has been mainly described as a mo vement disorder, but cognitive impairment is also increasingly noted. Metho ds: Thirty-five cases of clinically diagnosed CBDs were followed-up with cl inical, neuropsychological, and neuroimaging investigations. Twenty-nine pa tients were seen prospectively in movement disorder and cognitive neurology clinics; five of these came to autopsy. Six other autopsied cases that ful filled the clinical criteria of CBDs were added with retrospective review o f records. Results: All 15 patients presenting with movement disorders deve loped behavioral, cognitive, or language deficits shortly after onset or af ter several years. Patients presenting with cognitive problems (n = 20), pr ogressive aphasia (n = 13), or frontotemporal dementia (n = 7) developed th e movement disorder subsequently. Eleven cases with autopsy had CBD or othe r forms of the Pick complex. Conclusions: There is a clinical overlap betwe en CBD, frontotemporal dementia, and primary progressive aphasia. There is also a pathologic overlap between these clinical syndromes. The recognition of this overlap will facilitate the diagnosis and avoid consideration of C BD as 'heterogenous".