%0 Journal Article %J J Alzheimers Dis %D 2017 %T Predicting Development of Amyotrophic Lateral Sclerosis in Frontotemporal Dementia. %A Van Langenhove, Tim %A Piguet, Olivier %A Burrell, James R %A Leyton, Cristian %A Foxe, David %A Abela, Melissa %A Bartley, Lauren %A Kim, Woojin S %A Jary, Eve %A Huang, Yue %A Dobson-Stone, Carol %A Kwok, John B %A Halliday, Glenda M %A Hodges, John R %X

BACKGROUND: A proportion of patients with frontotemporal dementia (FTD) also develop amyotrophic lateral sclerosis (ALS).

OBJECTIVE: We aimed to establish the risk of developing ALS in patients presenting with FTD and to identify the relevant clinical variables associated with progression from FTD to FTD-ALS.

METHODS: Of 218 consecutive patients with FTD, 10.1% had a dual FTD-ALS diagnosis at presentation. The remaining 152 FTD patients with follow-up of at least 12 months were included in the present study. We calculated the rate of progression to FTD-ALS and compared the baseline characteristics of FTD patients who developed ALS to those who did not develop ALS.

RESULTS: Five percent of FTD patients developed ALS. The incidence rate of ALS was 6.7/100 patient-years in patients with FTD symptoms since 1 year, which declined with duration of FTD symptoms. No FTD patients developed ALS after 5 years. Five out of 8 FTD patients who developed ALS had presented with a mixed behavioral variant FTD and progressive non-fluent aphasia (bvFTD+PNFA) phenotype, 2 with bvFTD, and 1 with PNFA. Progression to FTD-ALS was significantly more frequent in patients with bvFTD+PNFA compared to those without this phenotype (pā€Š<ā€Š0.0001, OR 38.3, 95% CI: 7.3 to 199.2), and in FTD patients who carried the C9orf72 repeat expansion compared to those without the repeat expansion (pā€Š=ā€Š0.02, OR 8.0, 95% CI: 1.7 to 38.6).

CONCLUSIONS: FTD patients with a mixed bvFTD+PNFA phenotype and with a C9orf72 repeat expansion should be closely monitored for the possible development of ALS. The risk of developing ALS in FTD appears to decline with the duration of FTD symptoms.

%B J Alzheimers Dis %V 58 %P 163-170 %8 2017 %G eng %N 1 %1 http://www.ncbi.nlm.nih.gov/pubmed/28387671?dopt=Abstract %R 10.3233/JAD-161272