It soon may be possible for doctors to identify persons who have Alzheimer’s decades before dementia is present, allowing earlier intervention to protect the brain. This breakthrough in identification methods was reported on July 20 at the Alzheimer’s Association International Conference on Alzheimer’s Disease in Paris. The new insights come from an ongoing study: the Dominantly Inherited Alzheimer’s Network (DIAN), an international study of inherited forms of Alzheimer’s.
Based on what is seen in the study group, brain chemistry changes can be detected up to 20 years before the expected age of detectable symptoms. The Alzheimer’s-related changes can be specifically targeted for prevention trials in patients with inherited forms of Alzheimer’s.
The doctors are looking specifically at the value of disease indicators from cerebrospinal fluid analyses. DIAN researchers are studying members of families who have mutations in one of three genes: amyloid precursor protein, presenilin 1 or presenilin 2. Participants with these mutations are certain to develop Alzheimer’s disease early, with symptoms beginning in their 50s, 40s, or, in some rare cases, 30s.
Participants who carry the mutations but are still asymptomatic have significantly lower levels of amyloid beta and higher levels of tau protein in their cerebrospinal fluid than participants without the mutations.
Amyloid beta normally is cleared from the brain and into the spinal fluid. Scientists theorize that decreases in spinal fluid levels of amyloid beta reflect a buildup of this sticky protein fragment in the brain, where it forms Alzheimer’s plaques. Tau protein is a structural component of central nervous system cells. Its increase in cerebrospinal fluid is thought to be a byproduct of damage to brain cells.
DIAN is supported by funding from the National Institute on Aging. One hopes that our contentious political climate will not result in a loss of funding for this important work.
Lifestyle factors that are protective against amyloid and tau accumulation in the brain include fish and fish oil consumption, it is especially important to get adequate DHA which is specifically protective against the increases of amyloid.