Every aging baby boomer listens for the footsteps of Alzheimer's, and for good reason: It's estimated that 10 million American boomers will develop the disease. The need to develop preventative strategies, ideally long before Alzheimer's destructive, clinical symptoms appear, is critical.
In furthering the steps toward that goal, UCLA associate professor of neurology John Ringman and his colleagues confirm in the current issue of the journal Neurology that during Alzheimer's earliest stages, levels of specific proteins in the blood and spinal fluid begin to drop as the disease progresses, making them potentially useful as biomarkers to identify and track progression long before symptoms appear.
Identifying patients at the clinically "silent" stage is a prerequisite for advancing the strategies needed to prevent the symptoms from appearing. The hope is that one day, screening for such biomarkers could take its place beside such routine tests as colonoscopies and mammograms as another common tool of preventive medicine.
Familial Alzheimer's and sporadic Alzheimer's are two of the basic types of the disease. The majority of Alzheimer's cases are sporadic and late-onset, developing after the age of 65; the causes of this disease type are not completely understood. Familial Alzheimer's (FAD) is a rare form of the disease caused by certain gene mutations that affects less than 2 percent of Alzheimer's patients. FAD is early-onset, meaning the disease develops before age 65, and it is inherited; all offspring in the same generation have a 50-50 chance of developing FAD if one of their parents had it. The markers the researchers tracked came from people with the FAD mutations.
"Since we knew that 50 percent of first-degree relatives will inherit the same rare mutations, we were able to study the biochemical changes occurring in the cerebrospinal fluid and blood as long as 30 years before the subjects were likely to develop the disease themselves," said Ringman, who is the assistant director of the Mary S. Easton Center for Alzheimer's Disease Research at UCLA. "This allowed us to identify markers that might be used to diagnose the disease prior to the development of overt symptoms, and also tells us a lot about the chain of events that cause the disease."