Alzheimer’s disease, a progressive neurodegenerative disorder, is the most common cause of dementia worldwide. Think of it like a complex electrical system in the brain gradually losing its connections over time. There are around 55 million people living with dementia. Understanding its origins and the evolution of the scientific knowledge surrounding it is crucial for appreciating the strides made in research and treatment.

This article will take you through key moments in the discovery and understanding of Alzheimer’s, highlighting how far we’ve come and the ongoing efforts that offer hope for better diagnosis, treatment, and ultimately, a cure.

The Discovery of Alzheimer’s Disease

Alzheimer’s disease was first identified in 1906 by German doctor Alois Alzheimer. The discovery was made during his examination of a patient named Auguste Deter, who exhibited symptoms of memory loss, disorientation, and hallucinations. Upon her death, Dr. Alzheimer performed an autopsy and observed significant brain abnormalities, including amyloid plaques, which can be thought of as sticky clumps of protein that build up between nerve cells, and neurofibrillary tangles, which are like twisted fibers inside the nerve cells themselves. These findings were groundbreaking and laid the foundation for the study of Alzheimer’s disease.

Alois Alzheimer

In 1864, Alois Alzheimer was born in Marktbreit, Bavaria (Southern Germany). He studied medicine at several universities, including the University of Berlin and the University of Würzburg, eventually graduating with a medical degree in 1887. Alzheimer began his career at the state asylum in Frankfurt, where he met Emil Kraepelin, a psychiatrist who later named the disease after him. Dr. Alzheimer’s meticulous documentation of Auguste Deter’s condition and his innovative use of staining techniques to identify brain abnormalities were pivotal in his research.

Key Moments in Scientific Understanding

Since Dr. Alzheimer’s initial discovery, several key milestones have shaped our understanding of the disease.

1968: Cognitive Measurement Scale

In order to evaluate cognitive decline, researchers created the first measurement scale. With a cognitive measurement scale, researchers could connect the extent of cognitive impairment to the amount of damaged tissue and brain lesions present in the brain.

Today, a number of cognitive tests still exist to measure mental cognition and functioning. Keep in mind that cognitive tests can’t definitively diagnose Alzheimer’s disease, but they can be a useful tool throughout the diagnostic process.

1974: The National Institute on Aging

In October 1974, the U.S. Congress established the National Institute on Aging (NIA). The NIA is the main government agency responsible for Alzheimer’s and dementia research. The NIA works to improve the diagnosis, prevention, and treatment of Alzheimer’s.

1976: Alzheimer’s and Dementia

The term dementia is an umbrella term for a number of diseases that impact thinking, memory, and one’s daily life. Dementia can be caused by many different diseases, particularly those that damage the brain or nerve cells.

In 1976, neurologist Robert Katzman found that Alzheimer’s disease was the number one cause of dementia, highlighting the disease’s public health impact. Currently, Alzheimer’s disease may cause roughly 60 percent to 80 percent of dementia cases globally, according to the World Health Organization.

1984: Amyloid-Beta in Brain Plaques

Since Alzheimer’s initial discovery, it took roughly 80 years for more diagnostic progress to be made. In 1984, researchers George Glenner and Caine Wong successfully identified a key component of the disease called the amyloid-beta peptide, a small protein fragment.

The two researchers found amyloid-beta plaques — clumps of proteins — in the brains of some individuals with Alzheimer’s. They were able to identify amyloid-beta’s first 24 amino acids. This finding led to the hypothesis, or idea, that the accumulation of this amyloid-beta peptide might be the cause of Alzheimer’s since it may trigger nerve cell damage.

1985: Tau Protein

Once amyloid-beta was discovered in the brain plaques, scientists worked to identify the cause of neurofibrillary tangles, the other core component of the disease that Alois Alzheimer originally noted in 1906. These neurofibrillary tangles appear to be twisted threads that gather around neurons.

Jean-Pierre Brion and his team are credited with discovering the tau protein as the cause of neurofibrillary tangles. At first, neurofibrillary tangles could only be found during autopsies in the brain tissue of individuals with Alzheimer’s, but modern technology allows for the imaging of tau buildup in the brain and also in the blood and cerebrospinal fluid. Today, Alzheimer’s can be diagnosed with these tau biomarker tests.

1987: The First Alzheimer’s Gene

The first Alzheimer’s gene was discovered in 1987. The gene contributed to a rare form of the disease, known as familial Alzheimer’s disease, which occurs in approximately 5 percent to 10 percent of cases. Individuals with familial Alzheimer’s disease and this specific genetic mutation may develop symptoms as early as 30 years old to 40 years old.

1993: Genetic Risk Factors

Researchers soon identified a major genetic risk factor for Alzheimer’s called apolipoprotein-E (APOE). APOE can put individuals at risk for developing late-onset Alzheimer’s disease, which is the most common form of the disease, accounting for about 95 percent of all cases. It’s crucial to understand that while certain variations of the APOE gene can increase an individual’s risk of developing the disease, it is not a deterministic gene. Many people with the APOE risk gene never develop Alzheimer’s, and conversely, many people without it do.

Increased Public Awareness

Over the years, the definition and public awareness of Alzheimer’s disease have evolved significantly. Initially considered a rare condition, Alzheimer’s is now recognized as a major public health challenge affecting millions globally. The founding of the Alzheimer’s Association in 1980 played a crucial role in raising awareness and advancing research through clinical trials. Public campaigns, such as World Alzheimer’s Day, National Alzheimer’s Disease Month, and the Alzheimer’s Walk, have further helped to educate the public, reduce the stigma associated with the disease, and encourage participation in research efforts.

Current Research

There currently isn’t a cure for Alzheimer’s, but recent advancements in Alzheimer’s research have led to the development of new treatments and possible vaccine candidates aimed at slowing the progression of the disease. Although we’ve learned a lot about the condition so far, research is still ongoing. We can look forward to more advancements in the understanding and treatment of Alzheimer’s.

The discovery of Alzheimer’s disease by Dr. Alois Alzheimer in 1906 marked the beginning of a century-long journey to understand and combat this devastating condition. From identifying key pathological features to developing effective treatments, the scientific community has made remarkable breakthroughs. Continued research and public awareness efforts are essential in the fight against Alzheimer’s, offering hope for better treatments and quality of life.

Talk With Others Who Understand

On myALZteam, the social network for people with Alzheimer’s disease and their loved ones, more than 86,000 members come together to ask questions, give advice, and share their stories with others who understand life with the condition.

Did you know the history of Alzheimer’s disease? What finding surprised you the most? Share your experience in the comments below, or start a conversation by posting on your Activities page.