Sulcal morphology as predictor of cognitive decline over a 3‐year period in elderly at risk to develop Alzheimer’s disease

Abstract

AbstractBackgroundCerebral sulci openings have been consistently observed as larger in Alzheimer’s disease (AD) patients than in cognitively normal elderly. However, it remains unknown whether large openings may have predictive value of cognitive trajectories. We aimed to determine whether sulci openings might be predictors of changes in cognition over a 3‐year period in elderly people at risk to develop AD (at‐AD‐risk).MethodParticipants were recruited in memory and research centers in France between 2008 and 2011 in the framework of the MRI‐Multidomain Alzheimer Preventive Trial (MRI‐MAPT) ancillary study. They were non‐demented community‐dwelling women and men aged ≥ 70 years, and presented memory complaints and frailty criteria. In 20 sulci distributed throughout the brain, openings were extracted from Magnetic Resonance Imaging (MRI) T1‐weighted images obtained at baseline in 433 participants, using the Morphologist pipeline of BrainVISA [http://brainvisa.info, version 4.5.1]. Cognition was evaluated at baseline, 6, 12, 24, and 36 months of follow‐up with a composite Z score combining four cognitive tests (free and total recall of the Free and Cued Selective Reminding test, ten Mini‐Mental State Examination (MMSE) orientation items, Digit Symbol Substitution Test, and Category Naming Test). Linear mixed regression models explored the composite score variation over time according to the baseline openings magnitude.ResultAt baseline, participants were on average 74.8 (4.0) years old. The mean MMSE was 28.1 (1.5) and the mean composite cognitive score was 0.11 (0.62). Sulci openings were categorized into tertiles (T1, T2, T3) for the statistical analyses. The participants showing the largest openings (T3) in the left anterior inferior temporal sulcus presented a greater decline in the composite cognitive score over the 3‐year period of follow‐up (β=‐0.07, 95%CI [‐0.12; ‐0.02]) than the participants with lower openings values.ConclusionLarge openings of sulci within the lateral temporal area of the brain might be predictors of cognitive decline within 3 years in at‐AD risk individuals. These results may have strong applications in clinical setting and for preventive strategies.