Title: Determinants of Survival in Behavioural Variant Frontotemporal Dementia

Title: Determinants of Survival in Behavioural Variant Frontotemporal Dementia.

Authors: Beatrice Garcin, Patricia Lillo, Michael Hornberger, Olivier Piguet, Kate Dawson, Peter Nestor, John Hodges

Journal: Neurology

Abstract:

Background: Behavior variant FTD (bvFTD) is a common cause of non-Alzheimer dementia. Little is known about its rate of progression but a recently identified subgroup seems to have an excellent prognosis (phenocopy cases) whereas the pathological cases decline rapidly. Data about natural history are needed to provide the best information to the patients and their families.

Methods: We estimated survival in a large group of bvFTD patients (n=91) and reviewed their demographic and clinical features to determine how they affect prognosis.

Results: Median survival in the whole group of 91 patients was 10.6 years from symptom onset, and 7.3 years from diagnosis. Log rank tests showed that being a female, having a positive family history, language impairment and motor symptoms at first assessment were associated with a significant shorter survival. The estimated hazard ratio indicated that younger age at onset, a higher score on MMSE and ACE were associated with longer survival. After the exclusion of 24 “phenocopy” cases, the analysis was repeated in a subgroup of 67 patients. In this latter group, median survival was 7.9 years from symptom onset and 4.0 years from diagnosis. The only factor associated with shorter survival was the presence of language impairment.

Conclusions: The prognosis of bvFTD is poorer when there are language features at presentation. This study also provides evidence for the existence of a benign subgroup of patients with clinical features of bvFTD.