Spinal tap predicts Alzheimer’s disease susceptibility

The impetus for the study was the discovery that a decrease in beta-amyloid in the cerebrospinal fluid is associated with a toxic buildup of that protein in the brain, causing the plaques that are a hallmark of Alzheimer’s. Similarly, scientists worked off of the belief that an increase in tau protein in the cerebrospinal fluid is also correlated to tangles in the brain indicative of Alzheimer’s.

The study followed 137 patients over four to 12 years, tracking their progression from mild cognitive impairment (MCI), characterized by measurable memory problems, to full-on Alzheimer’s dementia. The doctors performed lumbar punctures periodically over the course of the study, measuring the concentrations of beta-amyloid and tau protein biomarkers in the patients’ cerebrospinal fluid. The results of this long-term investigation revealed that 90 percent of patients with MCI developed Alzheimer’s within nine to ten years of their initial consultation. Researchers noted that beta-amyloid levels are already fully decreased at least five to ten years before conversion to dementia, and further indicated that altered beta-amyloid metabolism precedes tau-related pathology and neuronal degeneration. These quantitative measurements may thus allow doctors to predict a patient’s future susceptibility to developing Alzheimer’s years prior to its symptomatic manifestation.

Researchers in this study expressed a future desire to employ this procedure to test asymptomatic aging adults, though such usage is not yet available. Add it to your yearly to-do list: get a mammogram, a colonoscopy ... and a spinal tap. Could aging be any more fun? One might wonder where these “routine” checkups – which are inconvenient at best and quite painful at worst – will end. Viewed in light of Alzheimer’s present characterization as incurable, one would not be amiss in questioning the point of going through such an ordeal. If you are heading towards irremediable mental oblivion over the ensuing years, do you really want to know?

The study emphasized that, while there is no cure for Alzheimer’s as of yet, new disease-modifying therapies are more effective when initiated during the early stages of the disease. This is because early detection will allow doctors to characterize the developing disease as either Familial or sporadic, and tailor treatment based on this classification. Furthermore, researchers depend on the public’s willingness to participate in clinical trials to further medical progress. As scientists gain more knowledge about the disease and how it develops, they will be able to formulate new drugs and treatments. To that end, many might feel compelled to participate in these spinal taps, even at the expense of becoming privy to some very bad news, in hopes of effecting future advancement toward a cure.