Differentiating cognitive impairment due to corticobasal degeneration and Alzheimer disease

Abstract

Objective: To identify clinical features that reliably differentiate individuals with cognitive impairment due to corticobasal degeneration (CBD) and Alzheimer disease (AD).Methods: Clinical features were compared between individuals with autopsy-proven CBD (n 5 17) and AD (n 5 16). All individuals presented with prominent cognitive complaints and were evaluated annually with semistructured interviews, detailed neurologic examinations, and neuropsychological testing. . Subsequent emergence of asymmetric motor/sensory signs, hyperreflexia, gait abnormalities, parkinsonism, falls, urinary incontinence, and extraocular movement abnormalities identified individuals with CBD, with $3 discriminating features detected in 80% of individuals within 3.1 years (95% confidence interval 2.9-3.3) of the initial assessment. Individuals with CBD exhibited accelerated worsening of illness severity and declines in episodic memory, executive functioning, and letter fluency. Semiquantitative pathologic assessment revealed prominent tau pathology within the frontal and parietal lobes of CBD cases. Comorbid AD neuropathologic change was present in 59% (10 of 17) of CBD cases but did not associate with the clinical phenotype, rate of dementia progression, or dementia duration. The clinical presentation of corticobasal degeneration (CBD) is notoriously heterogeneous, [1][2][3][4][5] contributing to diagnostic inaccuracy in 44% to 75% of clinically recognized cases. Conclusions3,4,6-11 A recent review of 210 autopsy-confirmed cases of CBD recognized 5 distinct clinical phenotypes, including corticobasal syndrome (CBS; 37.1%), progressive supranuclear palsy syndrome (23.3%), frontal behavioral-spatial syndrome (13.8%), an Alzheimer disease (AD) dementialike syndrome (8.1%), and a nonfluent/agrammatic variant of primary progressive aphasia syndrome (4.8%).9 Of these, only the AD dementia-like phenotype was excluded from proposed diagnostic criteria because of concerns that patients presenting with prominent cognitive impairment due to CBD or AD could not be reliably distinguished.

Cognitive impairment in progressive supranuclear palsy is associated with tau burden

“…Although the number of patients with PSP/AD was small and Alzheimer's‐type pathology was relatively mild, we found no significant difference in frequency and severity of CI in PSP compared with PSP/AD. This is consistent with literature reporting CI in corticobasal degeneration; 59% of corticobasal degeneration had Alzheimer's‐type pathology, but it had minimal effect on the rate of dementia progression and dementia duration . Although it remains inconclusive, there was not enough evidence to suggest that Alzheimer's‐type pathology affected cognition in PSP‐CI.…”

The Road to Recovery: A Pilot Study of Driving Behaviors Following Antibody-Mediated Encephalitis

“…Driving behaviors were monitored for a median of 29 months (range, [21][22][23][24][25][26][27][28][29][30][31][32]. No accidents were reported by study participants or captured by the DRIVES.…”

Age-Related Increase of Insulin-Degrading Enzyme Is Inversely Correlated with Cognitive Function in APPswe/PS1dE9 Mice

“…Almost all patients with Alzheimer’s disease, which includes familial AD and sporadic AD, have Aβ plaques deposited in brain tissue. Greater Aβ plaques accumulation also causes enhanced neuronal loss and leads to cognitive impairment [ 1 ]. Therefore, reducing the production of Aβ and promoting Aβ degradation have become one of ways to control the progression of AD.…”

“…Alzheimer’s disease (AD), a progressive neurodegenerative disorder, is already a major focus of research attention. AD causes functional impairment, like loss of cognitive functions and behavioral changes, which has severe effects on AD patients [ 1 , 2 ]. It was reported that over 46 million elderly people have cognitive impairment and memory loss caused by AD [ 3 , 4 ].…”