Samrah Ahmed, United Kingdom
Research Institute for the Care of Older People (RICE)Author Of 1 Presentation
IDENTIFYING COGNITIVE MARKERS OF DISEASE PROGRESSION IN POSTERIOR CORTICAL ATROPHY
Abstract
Aims
There are currently no established tools for monitoring disease progression in Posterior Cortical Atrophy (PCA), an atypical form of Alzheimer's disease. The characteristic visual dysfunction in PCA tends to be so severe at presentation that symptoms cannot be used to track further decline. Here, we explore the potential of Addenbrooke's Cognitive Examination (ACE) as an instrument for measuring PCA progression across cognitive subdomains.
Methods
Twenty participants with PCA and seventeen healthy adults completed repeated ACE assessments over 3-44 months. Trajectories of cognitive change on subdomains of the ACE were assessed using linear mixed effect models. Specifically, we investigated rate of decline in attention/orientation, memory, verbal fluency, and visuospatial skills.
Results
PCA patients had significantly lower scores on all cognitive domains at presentation compared to healthy controls. At baseline, PCA patients had an average score of 28% of visuospatial tasks, with a predicted decline to an average of 2% over the course of 30 months. Compared to controls, PCA patients showed a greater decrease in attention and verbal fluency scores over time. In contrast, longitudinal changes in memory scores did not differ between the groups.
Conclusions
As predicted, PCA patients were severely impaired on visuospatial tasks, impeding their use as a monitoring tool. In contrast, although scores on attention and verbal fluency also decreased to a greater extent than in healthy adults, they did not reach floor levels over a 30-month period. ACE measures of attention and verbal fluency may therefore hold promise as a marker of disease progression in PCA.