Before the First SymptomsWith the latest advances in imaging and biomarker research, experts are hoping to do something that they have never been able to do before—diagnose Alzheimer’s years before the first symptoms start to appear. Identifying those who are at higher risk of developing Alzheimer’s may be useful if we learn that particular lifestyle changes and new drugs in development can slow down or even reverse the course of the disease.
Family HistoryIn the less common familial early-onset Alzheimer’s dementia (cases that occur under age 60), gene mutations that are inherited are clearly associated with disease. The early-onset mutations occur in three genes, APP, PSEN1, PSEN2. These genetic changes increase the accumulation of beta amyloid in the brain. In the more common form of Alzheimer’s, genetic factors also play a major role, by affecting susceptibility to the disease. Gene variants like APOE4 increase the risk of an eventual Alzheimer’s diagnosis. Like the early onset genes, APOE affects accumulation of beta amyloid in the brain. Recently, 10 new late-onset Alzheimer’s genes have been indentified in scans of the human genome. Many of the new genes seem to affect amyloid levels in the brain. However, others influence the brain’s immune system or cholesterol metabolism.
Future Directions to Be Addressed for Biomarkers
- Standardization of biomarkers
- Application of biomarkers in community settings
- Application of biomarkers in clinical trials
- Competing/ ambiguous biomarkers
- Combination of biomarkers
- Identification of novel biomarkers