Entorhinal Cortex Thickness Predicts Cognitive Decline in Alzheimer's Disease

Abstract

Biomarkers for Alzheimer's disease (AD) based on non-invasive methods are highly desirable for diagnosis, disease progression, and monitoring therapeutics. We aimed to study the use of hippocampal volume, entorhinal cortex (ERC) thickness, and whole brain volume (WBV) as predictors of cognitive change in patients with AD. 120 AD subjects, 106 mild cognitive impairment (MCI), and 99 non demented controls (NDC) from the multi-center pan-European AddNeuroMed study underwent MRI scanning at baseline and clinical evaluations at quarterly follow-up up to 1 year. The rate of cognitive decline was estimated using cognitive outcomes, Mini-Mental State Examination (MMSE) and Alzheimer disease assessment scale-cognitive (ADAS-cog) by fitting a random intercept and slope model. AD subjects had smaller ERC thickness and hippocampal and WBV volumes compared to MCI and NDC subjects. Within the AD group, ERC> WBV was significantly associated with baseline cognition (MMSE, ADAS-cog) and disease severity (Clinical Dementia Rating). Baseline ERC thickness was associated with both longitudinal MMSE and ADAS-cog score changes and WBV with ADAS-cog decline. These data indicate that AD subjects with thinner ERC had lower baseline cognitive scores, higher disease severity, and predicted greater subsequent cognitive decline at one year follow up. ERC is a region known to be affected early in the disease. Therefore, the rate of atrophy in this structure is expected to be higher since neurodegeneration begins earlier. Focusing on structural analyses that predict decline can identify those individuals at greatest risk for future cognitive loss. This may have potential for increasing the efficacy of early intervention.

Juxtacortical Lesions and Cortical Thinning in Multiple Sclerosis

“…The most marked thickness loss (RRj compared with CISn) was in the right entorhinal cortex (8%), in line with the findings of Narayana et al 26 Entorhinal thinning is considered a predictor of cognitive decline in Alzheimer disease. 27 Our study did not include a neuropsychological evaluation; therefore, we could not analyze the value of entorhinal atrophy for predicting cognitive decline in our patients with MS. When following the entorhinal cortex, we found greater thinning at the right precuneus and cuneus (6%).…”

“…27 A study published by Bakshi et al 28 found the there was a correlation between the number of cortical and juxtacortical lesions for a given region and the cortical atrophy measured in that region. Discrepancy may arise again from the fact that we evaluated the presence and volume (not the number) of juxtacortical lesions, which actually represent a small percentage compared with cortical lesions.…”

Loss of gait control assessed by cognitive-motor dual-tasks: pros and cons in detecting people at risk of developing Alzheimer’s and Parkinson’s diseases

“…Importantly, these executive function components are known to interfere with gait (Maquet et al 2010;Morris et al 2016) and begin to decrease early in the disease course. Moreover, cognitive flexibility and inhibition depend on dopamine function in the basal ganglia (Berry et al 2016) and entorhinal cortex (Velayudhan et al 2013), respectively. Thus, our proposition, requiring more investigation, could open new avenues to use gait as a robust marker for prediagnostic AD and PD.…”

Magnetic resonance imaging and positron emission tomography in the diagnosis of neurodegenerative dementias

“…Accordingly, increased entorhinal cortex atrophy has been reported in AD patients (Teipel et al, 2006), with a high diagnostic accuracy. MCI subjects show an intermediate level of entorhinal cortex atrophy, between that observed in AD and the normal findings seen in healthy controls (Velayudhan et al, 2013). Morphometry of the enthorinal cortex, rather than the hippocampus, could be a better predictor of conversion to AD.…”