Microbleeds and Medial Temporal Atrophy Determine Cognitive Trajectories in Normal Aging: A Longitudinal PET-MRI
Marie-Louise Montandon1,2, François R Herrmann1, Valentina Garibotto3
1Department of Rehabilitation and Geriatrics, Geneva University Hospitals and University of Geneva, Switzerland.
Background:
The cognitive trajectories in normal aging may be affected by medial temporal atrophy (MTA) and amyloid burden, as well as vascular pathologies such as cortical microbleeds (CMB) and white matter hyperintensities (WMH).
Objective:
We addressed here the role of imaging markers in their prediction in a real-world situation.
Methods:
We performed a 4.5-year longitudinal study in 90 older community-dwellers coupling two neuropsychological assessments, MTA estimated with the Schelten's scale, number of CMB, and WMH evaluated with the Fazekas score at inclusion and follow-up, visual rating of amyloid PET and glucose hypometabolism at follow-up, and APOE genotyping. Regression models were built to explore the association between the continuous cognitive score (CCS) and imaging parameters.
Results:
The number of strictly lobar CMB at baseline (4 or more) was related to a 5.5-fold increase of the risk of cognitive decrement. This association persisted in multivariable models explaining 10.6% of the CCS decrease variance. MTA, and Fazekas score at baseline and amyloid positivity or abnormal FDG PET, were not related to the cognitive outcome. The increase of right MTA at follow-up was the only correlate of CCS decrease both in univariate and multivariable models explaining 9.2% of its variance.
Conclusion:
The present data show that the accumulation of more than four CMB is associated with significant cognitive decrement over time in highly educated elderly persons. They also reveal that the progressive deterioration of cognitive performance within the age-adjusted norms is also related to the increase of visually assessed MTA.
Insights
Accumulating four or more cortical microbleeds (CMB) significantly increases cognitive decline risk in older adults. Progressive medial temporal atrophy (MTA) also correlates with worsening cognitive performance over time.
Area of Science:
- Neurology
- Neuroimaging
- Gerontology
Background:
- Cognitive aging is influenced by medial temporal atrophy (MTA), amyloid burden, and vascular pathologies like cortical microbleeds (CMB) and white matter hyperintensities (WMH).
- Understanding the predictive role of imaging markers is crucial for assessing cognitive trajectories in normal aging.
Purpose of the Study:
- To investigate the predictive value of neuroimaging markers for cognitive decline in community-dwelling older adults.
- To explore the association between specific imaging pathologies and cognitive performance over a 4.5-year period.
Main Methods:
- A longitudinal study of 90 older adults with repeated neuropsychological assessments.
- Evaluation of medial temporal atrophy (MTA), cortical microbleeds (CMB), white matter hyperintensities (WMH), amyloid PET, and glucose hypometabolism.
- Regression models were used to analyze the relationship between imaging markers and cognitive decline.
Main Results:
- Four or more strictly lobar CMB at baseline predicted a 5.5-fold increased risk of cognitive decrement, explaining 10.6% of the variance.
- Medial temporal atrophy (MTA), Fazekas score, amyloid positivity, and abnormal FDG PET at baseline were not significantly associated with cognitive outcome.
- An increase in right MTA at follow-up correlated with cognitive decline, explaining 9.2% of its variance.
Conclusions:
- The accumulation of more than four CMB is a significant predictor of cognitive decrement in highly educated elderly individuals.
- Progressive medial temporal atrophy (MTA) is also associated with the deterioration of cognitive performance within age-adjusted norms.
