Many of us know someone or have a family member affected by Alzheimer’s disease.
According to an article published in the April 23/30, 2014 issue of the Journal of the American Medical Association, scientists are testing new therapies to delay or prevent the onset of the disease in healthy but at risk volunteers.
An estimated 5 million Americans age 65 and over have Alzheimer’s, and the number of people with the disease doubles for every 5 year interval beyond age 65. Unless an effective cure or preventive treatment is found, those numbers will rise, because the American population is aging.
Current Alzheimer treatment can be broken into two categories : Cholinesterase inhibitors, which boost levels of the neurotransmitter acetylcholine. Acetylcholine, which is responsible for cellular communication in the brain, is depleted in Alzheimer’s disease. Examples of these medications include donepezil (Aricept), galantamine (Razedyn) and rivastigmine (Exelon); and NMDA (N-methyl-d-aspartate) inhibitors, which increase the excitability of neurons. An example is menantine (Namenda).
Less than ½ of patients on these medications have any significant results, according to the current medical literature, and for this reason, researchers are designing studies of therapies to prevent or delay the onset of disease in asymptomatic, healthy, but at risk, volunteers.
Severe changes in the brain, such as accumulation of the protein fragment beta-amyloid, are found up to 20 years before patients are diagnosed with even the mildest form of Alzheimer’s. By the time any cognitive impairment is diagnosed, too much damage to the brain has occurred to be reversed by any experimental treatments.
According to the article in JAMA, several clinical trials are either under way, or will begin soon. Several of these trials will focus on testing antibodies against beta-amyloid in groups who are genetically predisposed to Alzheimer’s disease. Another trial will focus on older adults who are at risk, not because of a genetic mutation, but because their brain scans show signs of amyloid accumulation. They will also be given anti- amyloid antibodies, to see if the treatment makes a difference in cognitive decline.
Yet another study will test the ability of the diabetes drug, pioglitazone, to delay the onset of mild cognitive impairment. Pioglitazone, in addition to making the body more sensitive to insulin, also has an effect on mitochondrial function, another mechanism implicated in Alzheimer’s.
Although the scientific community is still very dedicated to finding a cure for those with symptomatic Alzheimer’s disease, prevention studies are instrumental to making a difference in the quality of life of our aging population.