Genetic Differences Important in Alzheimer's Diagnosis

A study by Sweden's Karolinska Institutet and Italy's Vita-Salute San Raffaele University published in Molecular Psychiatry uncovered genetic explanations for the differences between results yielded by two methods for detecting amyloid pathology in Alzheimer's disease. EurekAlert says the study involved positron emission tomography (PET) imaging and cerebrospinal fluid (CSF) analyses in 867 participants, including patients with mild cognitive impairment, Alzheimer's dementia, and healthy controls. Amyloid accumulation was monitored in a subset of nearly 300 participants documented with both a PET camera and CSF analysis for two years. The outcomes indicate that pathological changes in some individuals are first spotted in the brain with a PET camera, and in other individuals first with CSF analysis. In the latter, the researchers also observed greater incidence of Alzheimer's genetic risk factor and faster buildup of amyloid plaques in the brain. "The results may be important as amyloid biomarkers play a significant role as early diagnostic markers for clinical diagnosis," said first author Arianna Sala. "Today, CSF-analysis and PET are considered equivalent to determine the degree of amyloid accumulation, but the study indicates that the two methods should rather be seen as complementary to each other." Karolinska Institutet's Elena Rodriguez-Vieitez added that the study results "may also be important for the design of clinical trials of new drugs against amyloid accumulation in the brain."