Dataset Information

Disease progression in C9orf72 mutation carriers.

ABSTRACT:

Objective

To assess changes in 3 clinical measures, the Revised ALS Functional Rating Scale (ALSFRS-R), letter fluency, and Frontal Behavioral Inventory (FBI), over time in C9orf72 mutation carriers (C9+) with varied clinical phenotypes.

Methods

Thirty-four unrelated participants with mutations in C9orf72 were enrolled in a prospective natural history study. Participants were classified as asymptomatic, amyotrophic lateral sclerosis (ALS), ALS-familial frontotemporal dementia (FTD), or behavioral-variant FTD by clinical diagnostic criteria. Diagnostic cognitive and motor tests were repeated at 6 and 18 months. The ALSFRS-R, letter fluency, and FBI were administered at baseline and follow-up visits at 6, 12, and 18 months.

Results

The clinical diagnosis of most patients did not change over the follow-up. ALSFRS-R scores correlated with measures of motor function. Letter fluency correlated with FBI and cognitive tests. ALSFRS-R, letter fluency, and FBI differed among the C9+ diagnostic subgroups at enrollment and worsened over follow-up in symptomatic patients, with different slopes among the subgroups. Most patients survived to the 6-month time point after enrollment. Survival of C9+ patients with ALS and C9+ patients with ALS-FTD declined over the 12- and 18-month follow-up.

Conclusions

The pattern of scores of the ALSFRS-R, letter fluency, and FBI distinguished between ALS, ALS-FTD, and FTD presentations of C9orf72 mutation carriers and asymptomatic carriers. Longitudinal changes in these measures occurred with disease progression in a manner consistent with presenting phenotype.

SUBMITTER: Floeter MK

PROVIDER: S-EPMC5513817 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Publications

Disease progression in <i>C9orf72</i> mutation carriers.

Floeter Mary K MK Traynor Bryan J BJ Farren Jennifer J Braun Laura E LE Tierney Michael M Wiggs Edythe A EA Wu Tianxia T

Neurology 20170614 3

<h4>Objective</h4>To assess changes in 3 clinical measures, the Revised ALS Functional Rating Scale (ALSFRS-R), letter fluency, and Frontal Behavioral Inventory (FBI), over time in <i>C9orf72</i> mutation carriers (C9+) with varied clinical phenotypes.<h4>Methods</h4>Thirty-four unrelated participants with mutations in <i>C9orf72</i> were enrolled in a prospective natural history study. Participants were classified as asymptomatic, amyotrophic lateral sclerosis (ALS), ALS-familial frontotemporal ...[more]

PMID: 28615433

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