Abstract Details

Title Progression of Nonfluent Primary Progressive Aphasia and Primary Progressive Apraxia of Speech into Corticobasal Syndrome

Topic General Neurology

Presentation(s) S43 - General Neurology 2 (1:00 PM-1:12 PM)

Poster/Presentation
Number 001

Background Patients with nfvPPA and PPAOS can develop features of CBS, although it is unclear how commonly or early this occurs and whether they evolve to meet diagnostic criteria for probable CBS.

Objective

This study aimed to examine the evolution of nonfluent variant primary progressive aphasia (nfvPPA) and primary progressive apraxia of speech (PPAOS) into corticobasal syndrome (CBS).

Design/Methods We conducted a retrospective longitudinal study in 140 patients with nfvPPA or PPAOS who completed at least one visit where neurological and speech/language evaluations were performed (total of 329 visits). We applied the consensus criteria for possible and probable CBS at every visit, evaluating the presence of limb rigidity or akinesia, dystonia, myoclonus, limb apraxia, nonverbal oral apraxia (NVOA), and alien limb phenomenon. Given the strong association of NVOA with apraxia of speech, we also assessed a modified CBS criteria whereby we excluded NVOA as a criterion for CBS. The frequency of every CBS feature by year from disease onset was also assessed.

Results

Patients were followed on average 5.2 years from symptom onset (range: 0.4-15.9). Asymmetric akinesia, NVOA, and limb apraxia were the most common CBS features, while dystonia, myoclonus, and alien limb phenomenon were rare. 101 patients progressed to possible CBS and 4 to probable CBS. Using the modified criteria, 82 progressed to possible CBS and 4 to probable CBS. Patients with nfvPPA progressed to CBS earlier than those with PPAOS (p-value = 0.046) which was driven by limb apraxia that appeared earlier in nfvPPA (p-value = 0.0041). Both groups, however, had a similar proportion of progressors by the end of the follow-up period.

Conclusions Patients with nfvPPA and PPAOS frequently develop CBS features, although they rarely meet probable criteria even after long follow-up. Those with nfvPPA show a faster trajectory to CBS than those with PPAOS although PPAOS catches up later.

Authors/Disclosures
Danna P. Garcia-Guaqueta, MD PRESENTER	Dr. Garcia-Guaqueta has nothing to disclose.
Hugo Botha, MD (Mayo School of Graduate Medical Education, Rochester)	Dr. Botha has received research support from NIH.
Rene Utianski	No disclosure on file
Joseph Duffy	No disclosure on file
Heather Clark	No disclosure on file
Austin Goodrich	No disclosure on file
Mary M. Machulda, PhD (Mayo Clinic)	The institution of Dr. Machulda has received research support from NIH.
Jennifer Whitwell, PhD (Mayo Clinic)	Dr. Whitwell has nothing to disclose.
Keith A. Josephs, Jr., MD, FAAN (Mayo Clinic)	Dr. Josephs has nothing to disclose.