Year: 2020
Type: article
Study design: Observational Study
Abstract: Background Heterogeneity in the pattern of cognitive deficits seen in probable AD patients is well recognized. Two reliably reproducible profiles are ones that have an extreme deficit in either visuo‐spatial (Vis‐D) or language (Lang‐D) domains compared to all other domains, independent of memory performance. Information on variability in progression rates and overall survival associated with these profiles is lacking. Method Right handed probable AD patients followed longitudinally in a memory clinic, 50‐90 years old with baseline MMSE score ≥10, were classified as Vis‐D or Lang‐D if their scores on tests of visual and language function varied by ≥ 2 standard deviations. Proportional hazards analysis was used to compare time to reach an MMSE < 10, CDR global score=3, and survival time from diagnosis to death in Vis‐D, Lang‐D and balanced deficits (Bal‐D) groups, adjusting for age, sex, education, ethnicity, baseline co‐morbidity, and APOE genotype. Result Of 540 patients meeting inclusion criteria, 86 (15.9%) were Vis‐D and 61 (11.3%) were Lang‐D. Median follow‐up time after baseline was 3.30 years (range 0.9, 13.3) and median time to death was 5.50 years (range=1.0, 16.8). The Vis‐D group was younger at diagnosis and had a higher prevalence of APOE e4 homozygosity than the Lang‐D and Bal‐D groups (69.8±8.5 vs 76.3±7.1 and 75.0±7.5 years and 25.9% vs 10.2% and 14.1% APOE e4 homozygosity respectively). Lang‐D patients reached a severe stage on the MMSE more rapidly than Vis‐D and Bal‐D (HRLang‐d vs Bal‐D=1.68, 95% CI=0.99‐2.73, p=.054; HRLang‐D vs Vis‐D=2.04, 95% CI=1.06‐3.78, p=.032). Results for the CDR endpoint were similar (HRLang‐D vs Bal‐D=1.64, 95% CI=1.04‐2.56, p=.032; HRLang‐D vs Vis‐D=2.32, 95%CI=1.40‐4.57, p=.002). Cognitive profile did not affect time to death. Conclusion Probable AD patients with a Lang‐D cognitive profile decline faster on the MMSE and CDR than those with other cognitive profiles. Cognitive profile at diagnosis does not affect overall survival. Understanding the neuropathology underlying these cognitive profile differences could have implications for development or selection of disease modifying treatments.
Source: Alzheimer s & Dementia
DOI: 10.1002/alz.041265
Authors: Ajay Sood, Valory N. Pavlik, Eveleen Darby, Wenyaw Chan, Rachelle Doody
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W3111092125