Four‐year cognitive decline in mild cognitive impairment patients with distinct baseline neuroanatomical atrophy profiles: A MEMENTO and QyScore® study.

Abstract

AbstractBackgroundNeuroanatomical atrophy profile is increasingly recognized as a valuable characterization in mild cognitive impairment (MCI) individuals and may provide prognostic information about cognitive decline.Method1153 MCI participants from the MEMENTO memory clinic study with 48‐month longitudinal follow‐up were included (mean (sd) Age=70.6 (8.2), 60% female, CDR‐SB=0.63 (0.72)). QyScore® volumetric quantification was applied to baseline 3DT1 images and four recognized neuroanatomical subtypes defined based on regional atrophy with respect to an internal normative database (z<‐1.64) [1,2]: no/minimal atrophy [N‐] (n=1,012), limbic predominant: LP (n=37), hippocampal sparing: HS (n=84) and combined hippocampal and cortical atrophy [typical/diffuse: TD] (n=20). 145 participants were amyloid positive (A+) via CSF or PET (Age = 73.7 (5.9): 47% female: N‐=114, LP=8, HS=21 and TD=2). All participants underwent cognitive and functional assessments at baseline and 48 months, including mini‐mental state examination (MMSE), clinical dementia rating (CDR), Free and Cued Selective Reminding Test (FCRST) and Instrumental Activities of Daily Living (IADL) scale. Linear regression analysis (correcting for age, sex and baseline performance) investigated the relationship between baseline neuroanatomical subtype and subsequent 4‐year cognitive decline. Bonferroni correction was applied.ResultAt month 48, all subtypes demonstrated significant decline across memory, orientation, and executive function. Severity of decline varied across subscales and subtype and was particularly marked in A+ LP individuals (Figure 1). IADL remained stable for the N‐ and TD subgroups. 143 participants converted to dementia [102=N‐, 18=LP, 15=HS, and 8=TD subtypes, representing 10%, 49%, 18% and 40% of the total N‐, LP, HS and TD atrophy subtypes respectively]. HS and N‐ individuals also demonstrated the least decline across all domains and did not significantly differ on any tests. LP atrophy subtype demonstrated the greatest decline across all cognitive domains as well as global CDR and IADL (p<0.001 compared with N‐ and HS subtypes). Similarly, TD phenotypes showed significant decline across multiple cognitive subscales compared with N‐ and HS subtypes (p<0.001) particularly for orientation and global CDR.ConclusionEarly atrophy profiles in MCI populations can provide insights into the domains and severity of future patient progression over 4 years.[1] Planche et al., (2020)[2] Schwarz et al., (AAIC2022)