Brain cortical thickness in the general elderly population: the Rotterdam Scan Study

Area of Science:

• Neuroimaging
• Neurology
• Gerontology

Background:

• Cortical thickness is a potential biomarker for neurodegenerative diseases.
• The influence of demographic and vascular risk factors on cortical thickness is not fully understood.
• Investigating these relationships is crucial for understanding brain aging and disease.

Purpose of the Study:

• To examine aging effects on global and lobar cortical thickness in a non-demented elderly population.
• To investigate the association of demographic variables and cardiovascular risk factors with cortical thickness.

Main Methods:

• Utilized a population-based sample of 1022 non-demented elderly individuals (mean age 68.4±7.3 years).
• Employed a validated model-based approach to calculate mean cortical thickness (μm) from brain MR images.
• Analyzed associations between cortical thickness and age, sex, education, diastolic blood pressure, intra-cranial volume, diabetes mellitus, and HDL cholesterol.

Main Results:

• Women exhibited significantly thicker cortices than men (p<0.01).
• Cortical thickness decreased with age (~0.2% per year), with the most pronounced effects in the occipital and temporal lobes.
• Age-related cortical thinning in the frontal lobe was more pronounced in men (p-interaction<0.001).
• Higher education, diastolic blood pressure, and intra-cranial volume correlated with thicker cortices.
• Diabetes mellitus and higher HDL cholesterol levels were associated with thinner cortices.

Conclusions:

• Cortical thickness is influenced by age, sex, education, and cardiovascular risk factors in non-demented elderly individuals.
• These findings highlight the complex interplay of factors affecting brain structure during aging.
• Understanding these associations may aid in identifying individuals at risk for neurodegenerative conditions.