Researchers are making headway in identifying — and perhaps even preventing — Alzheimer’s disease, the most common form of dementia. Here’s a roundup of some of the most recent developments in the field.
Game-changing blood test
Researchers have developed a simple blood test to detect the presence of beta-amyloid (Aβ) protein in the brain, a hallmark of Alzheimer’s disease, and some experts are calling it a game changer. The test, intended for use in patients who have some cognitive impairment, requires only a small amount of blood (as little as a teaspoon). A specialized laboratory analyzes the sample for beta-amyloid concentrations and determines the likelihood (low, intermediate or high) of Aβ plaques having formed in the brain.
A study by the company that developed the test showed it correctly identified brain amyloid plaque status in 86 per cent of patients. The company stresses that the test, by itself, can’t diagnose Alzheimer’s but could be an important tool to aid in the evaluation process. Typically, brain beta-amyloid plaques are detected using positron emission tomography (PET) scans, which are expensive and often difficult to access.
Eyes: A window into the brain
Investigators have identified the presence of beta-amyloid in the retinas of living patients who are experiencing cognitive decline and correlated these data with evidence of changes in the subjects’ brains. This work suggests that retinal Aβ may appear before deposits form in the brain.
Experts believe retinal amyloid screening could be a quick, easy and inexpensive tool to detect signs of Alzheimer’s. Uncovering amyloid in the eye may allow clinicians to identify the disease at earlier stages, even before symptoms appear, when it may be more treatable. Then, once a patient meets a certain predefined retinal amyloid threshold, doctors could monitor this marker, much as they might high triglyceride or blood glucose levels.
Protection via flu shots
Research suggests the relatively cheap and readily available seasonal flu shot may reduce a person’s chances of developing Alzheimer’s. One study found that receiving at least one flu vaccination was associated with a 17 per cent reduction in Alzheimer’s risk.
Another study discovered that people who were inoculated against pneumonia between the ages of 65 and 75 cut their Alzheimer’s risk by up to 40 per cent. Investigators say more research is needed to uncover the biological mechanism that might be responsible for this protective effect.
High-intensity physical activity
Results from research conducted in McMaster University’s NeuroFitLab suggest that it’s never too late to get the memory-enhancing benefits of physical activity. The study, which enrolled healthy but sedentary older Canadians in a 12-week exercise program, showed that memory among those who completed high-intensity interval training improved by up to 30 per cent. The workout, completed three times a week, involved four 4-minute sets of high-intensity exercise on a treadmill followed by a recovery period.
Exercise boosts memory by promoting growth of new neurons in the hippocampus area of the brain. These neurons contribute to the creation of more-detailed and -accurate memories; for example, being able to correctly remember if you took your medication today or where you parked your car. However, only study subjects who did more strenuous exercise experienced the benefits; participants who completed a program of moderate-intensity, continuous aerobic training, and those doing just stretching exercises, did not demonstrate improved memory.
Mounting evidence points to the cognitive benefits of a high-fat, low-carbohydrate ketogenic diet that contains adequate protein. The diet, which reduces seizures in some children with drug-resistant epilepsy, helps break down fats into chemicals called ketones.
It’s believed that ketones may enhance healthy neuron growth and reduce inflammation that contributes to cognitive decline. This, experts say, means the diet could delay, improve or prevent the progression of memory deterioration. But they caution not to try this regimen unsupervised.