Age, hypertension, and genetic polymorphisms and their relative associations with white matter hyperintensities in Korean patients with Alzheimer’s disease

ABSTRACT

Objectives: White matter hyperintensities are known to influence dementia in Alzheimer’s disease. Genetic components are suggested as putative risk factors for vascular pathology and cognitive decline. This study aimed to determine whether there is an association between candidate genetic polymorphisms and the severity of white matter hyperintensities in patients with Alzheimer’s disease. Methods: Seventy-five patients diagnosed with Alzheimer’s disease underwent genetic tests for specific alleles of apolipoprotein E, angiotensin-converting enzyme, and methylenetetrahydrofolate reductase. All patients underwent brain magnetic resonance imaging scans and neuropsychological tests. The severity of white matter hyperintensities was semiquantified using the CREDOS rating scale, and patients were divided into three groups according to their rating. Results:The severity of white matter hyperintensities was related to age and hypertension. However, none of the gene polymorphisms we tested was found to be associated with the severity of white matter hyperintensities. Conclusion:The genetic polymorphisms found in apolipoprotein E, angiotensin-converting enzyme and methylenetetrahydrofolate reductase did not contribute to white matter hyperintensities in Alzheimer’s disease.Only age and hypertension factors were found to be contributory to white matter hyperintensities.