Abstract
Background/Objectives Nearly thirty thousand Australians under the age of 65 live with dementia. Posterior Cortical Atrophy (PCA) is one form of young onset atypical dementia, often caused by Alzheimer disease. Due to its rarity, atypical phenotype and young onset, the diagnosis is often missed for years. A consensus expert opinion diagnostic framework was created in 2017 to reduce delays to diagnosis. We aimed to test the validity of this framework in a real-world PCA population.
Methods We completed a retrospective audit of Eastern Cognitive Disorders Clinic (ECDC) patients with a clinician-determined final diagnosis of PCA (N=32) 2008–2022: age at diagnosis, time to diagnosis and the clinical, cognitive, and neuro-imaging features. We compared our patients’ presentations with the core cognitive features included in the framework and their presence at first assessment.
Results Thirty (93.8%) ECDC clinician diagnosed PCA patients fulfilled the criteria: cognitive features correlated well with the framework for the top four features (visuo-spatial and -perceptual deficits, simultanagnosia, constructional apraxia). 100% of patients had MRI brain, but only 38% were reported as PCA; 84% had FDG-PET brain with 59% reported as PCA. Most (28, 87.5%) presentations were in keeping with a PCA-pure syndrome. Three patients met criteria for PCA-plus-CBS and one for PCA-plus-DLB. Average delay to diagnosis was 4 years with mean symptom onset at age 59 years.
Conclusion Our patients’ cognitive features closely aligned with the consensus framework, corroborating its real-world applicability. Neuroradiological reporting was identified as a key challenge. This represents new Australian data on PCA syndromic diagnosis.
