Clinical features of pathologic subtypes of behavioral--variant frontotemporal dementia

To identify clinical features in behavioral-variant frontotemporal dementia that may help predict tau-positive pathology.

Clinical and historical features of patients with pathologically confirmed tau-positive and tau-negative frontotemporal lobar degeneration from 1970 to 2006 were retrospectively reviewed in a blinded fashion. The initial clinical features of those patients who eventually met consensus criteria for frontotemporal dementia were examined using univariate and cluster analyses to explore characteristics that may be associated with tau pathology.

Fifty-six patients (24 tau-positive cases) were included in the analysis. There was no difference in demographics between the tau-positive and tau-negative cases. Univariate analysis showed that poor planning and/or judgment was more commonly associated with tau-positive pathology (P = .03). Cluster analysis using behavioral characteristics identified 2 groups of patients: cluster 1 contained mainly tau-positive cases (57%) and cluster 2 was mostly tau-negative cases (71%). Poor planning and/or judgment was a common presenting sign in the first group (P < .001), while the second group was more likely to present with impaired regulation of personal conduct (P < .001) and a decline in personal hygiene (P = .005).

Poor planning and/or judgment was associated with behavioral-variant frontotemporal dementia patients who had tau-positive pathology. The constellation of impaired personal conduct and a paucity of dysexecutive symptoms identified tau-negative patients.