Screening for Cognitive Dysfunction in Corticobasal Syndrome: Utility of Addenbrooke’s Cognitive Examination

Abstract

Introduction: The motor features of corticobasal syndrome (CBS) are well recognized but the fact that many, if not all, affected patients develop cognitive impairment is still underrecognized. The dementia of CBS overlaps most with a language variant of frontotemporal dementia: progressive nonfluent aphasia (PNFA). The aim of this study was to determine the usefulness of Addenbrooke’s Cognitive Examination-Revised (ACE-R) in the evaluation of CBS and to document similarities and differences between CBS and PNFA. Materials and Methods: Patients with well-defined CBS or PNFA from two tertiary referral centers were selected along with matched controls. Results: Twenty-one patients with CBS, 23 patients with PNFA and 47 age- and education- matched controls were included. Both CBS and PNFA groups showed substantial impairment on the ACE-R (f = 17.3–80.2, p < 0.001) and were significantly impaired in all domains (p < 0.001). The only significant difference between CBS and PNFA was in the visuospatial domain (p < 0.009), being worse in CBS. Using a cutoff of 88/89 out of 100, 90% of CBS and 82.6% of PNFA patients were impaired. At this cutoff of 88/89, ACE-R in CBS had sensitivity and specificity values of 91 and 98%, respectively.

The Addenbrooke's Cognitive Examination Revised as a potential screening test for elderly drivers

“…Driving impairments might be expected in various populations, as normal aging, clinical neurologic disease (namely, Alzheimer's Disease, Parkinson's Disease, Multiple Sclerosis, Stroke) and psychiatric conditions (namely, Major Depression, Schizophrenia) that affect a person's cognitive functioning and may impact driving ability (Marcotte and Scott, 2009). ACE-R research has examined these conditions (e.g., Alexopoulos et al, 2010;Dudas et al, 2005;Hamilton et al, 2009;Kwak et al, 2010;Mathew et al, 2011;Pendlebury et al, 2012;Reyes et al, 2009).…”

Cognitive dysfunction in corticobasal degeneration

“…In one study, the ACE-R detected cognitive dysfunction in 90% of CBS patients with 91% sensitivity and 98% specificity using a cutoff of 88 to 89. In comparison with progressive nonfluent aphasia, CBS showed a similar cognitive impairment profile, except for poorer visuospatial function in CBS 52 . Another study evaluating the ACE-R in 135 patients with parkinsonian syndromes (86 PD; 30 PSP; 19 CBD) 51 proposed that the verbal fluency subscore was an objective contributor to differentiate parkinsonian syndromes.…”

“…It is well established that CBD patients have a marked visuospatial dysfunction 52,54 . Like language dysfunction, visuospatial deficits also present as a spectrum of symptoms, including Balint's syndrome.…”

“…Recently, two studies proposed the Addenbrooke's Cognitive Examination Revised (ACE-R) for both objective screening and cognitive diagnosis of CBD and other parkinsonian syndromes 51,52 . This test combines the agility of the Mini-Mental State Examination, with a better evaluation of memory, language, visuospatial cognition and verbal fluency.…”

“…This cognitive syndrome can be present in a bunch of tauopathies, classically in fronto-temporal dementia, but also in AD 52 . Beyond nonfluent aphasia, patients may also experience marked reduction of speed fluency and grammar deficits 52 . Language evaluation comprises naming, comprehension, repetition, reading and writing.…”