Cognitively healthy Indians with higher Framingham Cardiovascular Risk Scores have higher WMH burden with lesser grey matter, white matter and hippocampal volumes
Jonas S. Sundarakumar, Abhishek Mensegere Lingegodwa, Thomas Gregor Issac- Psychiatry and Mental health
- Cellular and Molecular Neuroscience
- Geriatrics and Gerontology
- Neurology (clinical)
- Developmental Neuroscience
- Health Policy
- Epidemiology
Abstract
Background
Increasing evidence indicates the important role of cardiovascular risk factors in dementia risk, particularly in Indians. It is known that cardiovascular risk factors tend to cluster together, and a widely used multivariable risk scoring is the Framingham Cardiovascular Risk Score (FRS). However, very little is known about the association between FRS and structural brain MRI parameters in cognitively healthy Indians.
Method
Baseline clinical and brain MRI data of 487 cognitively healthy Indians (Clinical Dementia Rating score of ‘0’), who are part of two ongoing, large, aging cohort studies in India – Srinivaspura Aging, Neuro Senescence and COGnition study (SANSCOG) study (n = 200) and Tata Longitudinal Study of Aging (TLSA, n = 289) were utilized. FRS was calculated using clinical and blood biochemistry data, whereas brain MRI scans were performed on 3T MRI scanners. White matter hyperintensity (WMH) lesion segmentation was performed using Lesion Segmentation Toolbox (LST) and brain volumes (total grey matter, total white matter, 3rd ventricle, right and left hippocampus) were derived using FreeSurfer software and normalized according to total intracranial volumes of the respective subjects. Linear regression analysis was performed with FRS as independent variable and various structural MRI parameters as dependent variables. A p value of <0.05 was considered significant.
Result
Urban subjects with higher FRS had significantly higher WMH volume (ß = 0.00011, p<0.001, R2 = 0.130), lower grey matter (ß = ‐0.00285, p<0.001, R2 = 0.206), white matter (ß = ‐0.00180, p<0.001, R2 = 0.106), right hippocampal (ß = ‐0.00004, p<0.001, R2 = 0.180), left hippocampal (ß = ‐0.00003, p<0.001, R2 = 0.156) volumes and higher 3rd ventricle volumes (ß = 0.00003, p<0.001, R2 = 0.150). Rural subjects higher FRS had lower grey matter (ß = ‐0.00166, p<0.001, R2 = 0.118, white matter (ß = ‐0.0011, p<0.001, R2 = 0.060), right hippocampal (ß = ‐0.00002, p<0.001, R2 = 0.087), left hippocampal (ß = ‐0.00002, p<0.001, R2 = 0.084) volumes and higher 3rd ventricle volumes (ß = 0.00004, p<0.001, R2 = 0.264) but no significant association was seen with WMH volume.
Conclusion
These findings indicate that cardiovascular risk is associated with structural brain changes in cognitively healthy Indians. Since cardiovascular risk can be reduced through cost‐effective community level strategies, such as lifestyle‐based interventions, promptly addressing this risk in Indians could be an important part of dementia prevention strategies.