For now, there is no cure for either disease, though scientists continue to pursue a variety of avenues in their search. Vaccination currently seems the most popular.
According to the World Health Organization, dementia (an umbrella term than encompasses AD) is the fastest-growing global health epidemic. As we get healthier and live longer, the incidence of dementia increases.
The prevailing hypothesis about its cause involves the amyloid precursor protein (APP), which resides in the outer membrane of nerve cells. If these proteins are not routinely broken down, they can form a harmful substance called beta-amyloid, which accumulates as plaque and kills brain cells.
A decade ago, the first human vaccination study resulted in too many adverse reactions and was discontinued. That vaccine activated certain white blood cells (T cells), which attacked the body's brain tissue.
The new treatment, used in a study led by Karolinska Institutet in Sweden, involves active immunization with a vaccine designed to trigger the body's immune defense against beta-amyloid. The researchers found that 80 percent of patients involved in the trials developed their own protective antibodies against beta-amyloid without suffering any adverse side effects over the three years of the study.
The researchers believe that patients with mild to moderate Alzheimer's can tolerate the CAD106 vaccine used in this study. As is so often the case, larger trials must now be conducted to confirm the vaccine's efficacy.
Source: Lancet Neurology, June 6, 2012