New Delhi: A recent study published in Alzheimer's and Dementia has revealed that brain shrinkage in Alzheimer’s disease (AD) is far from uniform, with each patient exhibiting unique patterns of atrophy.

The Researchers from University College London (UCL) and Radboud University employed neuroanatomical normative modelling to track how Alzheimer's disease affects different regions of the brain in personalized ways.

The study analysed MRI data from 86 patients diagnosed with Alzheimer's disease and compared it against a healthy reference cohort of 33,072 individuals. This detailed comparison identified specific brain regions most affected by Alzheimer's-related atrophy, with the superior temporal sulcus showing the highest percentage of atrophy in 60% of patients.

However, the research demonstrated that overlap in brain atrophy patterns between individuals remained low, pointing to significant variability in how Alzheimer's disease progresses.

"Brain atrophy in AD is highly heterogeneous, and neuroanatomical normative modelling can be used to explore anatomo-clinical correlations in individual patients," the researchers noted. This technique provides insights into the individualized progression of Alzheimer’s disease, enabling a deeper understanding of how the condition uniquely affects each patient.

The study further revealed that patients exhibiting non-amnestic symptoms (which differ from typical memory loss symptoms), those in advanced stages of Alzheimer’s, and those without depressive symptoms had a higher total count of brain regions affected by atrophy.

Notably, the study found a negative correlation between amyloid burden (the build-up of amyloid plaques in the brain) and the total outlier count, indicating that amyloid accumulation alone may not fully explain brain atrophy in Alzheimer’s patients.

One key finding was the importance of cortical thinning in different brain regions, which showed significant variation across patients. The variability may stem from the influence of additional cognitive conditions, such as vascular dementia or frontotemporal dementia, or be influenced by lifestyle factors such as smoking, alcohol use, or previous brain injuries.

This highlights the complexity of diagnosing and treating Alzheimer's, emphasizing the need for personalized therapeutic approaches that address specific areas of brain degeneration in each individual.

The researchers suggest that these insights into the progression of brain atrophy in Alzheimer’s disease may pave the way for personalized medicine. Treatments could potentially be tailored to target the exact regions of the brain most affected in each patient, improving outcomes and slowing the progression of the disease.

This study represents a significant step forward in understanding the complex nature of Alzheimer's and the individual factors that contribute to its progression.

Rishika Verma
Rishika Verma