Alzheimer’s disease

In 1976...

Although German psychiatrist Alois Alzheimer first described a brain disease with abnormal clumps (amyloid plaques) and tangled fibers (neurofibrillary tangles) as early as 1901, Alzheimer’s disease (AD) was still virtually unknown in 1976.

“Medical textbooks rarely dedicated more than one paragraph to describing it back then,” says Dr. Peter St. George-Hyslop, a world authority on the genetics of AD, who was but a medical student at the time.

“Research into Alzheimer’s, as a dedicated effort, did not earnestly begin until the 1980s,” he explains. Dr. St. George-Hyslop is now Director of the Centre for Research in Neurodegenerative Diseases at the University of Toronto. In fact, not until the 1990s were a group of drug treatments developed to give genuine, if modest, symptomatic improvement to Alzheimer’s patients.


Contemporary research on AD is accelerating worldwide. Approximately 400 pharmaceutical treatments are currently being investigated to find better ways to treat the disease, delay its onset, and prevent it from developing in the first place. Advances are occurring on all fronts, including imaging studies to identify AD in the living brain (a conclusive diagnosis of AD can still only be made through an autopsy), blood tests that may one day be used to diagnose AD, and genetic research on risk factors associated with the disease.

There have been fundamental improvements in our understanding of the disease itself. Many scientists feel that we are on the verge of testing the first generation of drugs directed at the disease process directly, not just AD symptoms. Dr. St. George-Hyslop and his team of researchers have discovered genes responsible for the early onset of AD and identified a key protein that causes nerve cell degeneration, which might very well lead to a new drug that would regulate the progression of AD.

“I think the most fundamental realization that we have had in recent years,” says Dr. St. George-Hyslop, “is that Alzheimer’s is not an uncommon or rare disease.” Today we know that AD is progressive and ultimately fatal. It affects an alarming 30% to 50% of Canadians over the age of 85 and is the most common form of dementia. The annual cost of caring for people with dementia in Canada is currently estimated at $2.9 billion.


Scientists still need to learn a lot more about what causes AD and are studying education, diet, and environment to learn what role these factors play in the development of the disease.

A firm body of evidence suggests that certain risk factors, such as diabetes and cholesterol, may increase the chances of developing AD, while other factors, such as physical, mental, and social activities, may act as protective measures against the disease. The major unknown in Alzheimer’s research is precisely how such factors combine to either promote or discourage the development of AD.

“I think the important thing for Canadians to remember is that there is optimism, and that optimism is driven by research,” insists Dr. St George-Hyslop. “Without research you stay where you are.”

Dr. St George-Hyslop stresses that we have learned most of what we know today only in the past 15 years and that discoveries are happening at a faster pace every single day. “The next 10 years could be more exciting than the last 100.”