Alzheimer's disease is a medical condition caused by changes in the brain. These changes can affect various aspects of life, like memory, behaviour, problem-solving skills and daily activities.[1,2] Over time, the symptoms of Alzheimer’s disease slowly progress, which can impact a person's ability to live independently.[1,2] These changes in the brain can begin up to 20 years before the first symptoms become noticeable and are thought to be linked to two proteins: beta-amyloid and tau.[1,2] These proteins accumulate in the brain and form ‘plaques’ or ‘tangles’, that block the brain from sending and receiving signals. Scientists are currently exploring these proteins, aiming to find potential treatments that could slow down or even halt the progression of Alzheimer's disease.
Spotting Alzheimer’s as early as possible offers a valuable opportunity for individuals and their families to gain a better understanding and plan for the journey ahead. It also allows physicians to recommend suitable interventions and treatment options. It is important to note that many people may think that the symptoms of Alzheimer’s are a natural part of ageing, but it is not true. The disease causes the abnormal functioning of our brain parts that are responsible for memories, emotions, reasoning and sensory perception.[2,3] The hippocampus is a part of our brain that is often one of the first to be affected by Alzheimer’s, that is essential for forming new memories.
Alzheimer's progression varies from person to person, and over the years, it extends to other regions of the brain like the amygdala (regulates emotions), left hemisphere (involved in language and reasoning), frontal lobe (controls consciousness, problem solving and attention), and right parietal lobe (helps us understand and navigate three-dimensional).[3,4] While symptoms may slowly progress over time, improving our understanding of how this disease affects us empowers us to better plan for the future and provide care for our loved ones.[1,2]
Scientists are still working to understand what exactly causes Alzheimer's, but we know that the greatest risk factor is age. Though Alzheimer's disease is not a normal part of ageing, it is more common in elderly people. It typically affects people older than 65 years, but some people can develop it earlier, which is called ‘early-onset’ Alzheimer's disease.
Another factor for Alzheimer’s disease is genetics. In most cases, having a family history of Alzheimer's disease increases your risk, but it does not mean that you will definitely develop Alzheimer's disease. The gene most strongly associated with Alzheimer's is called apolipoprotein E (APOE) that comes in different forms known as alleles. We inherit one allele from each parent. One of these alleles, APOE ε4, may increase a person's risk for Alzheimer's disease by 8 to 12 times if they inherit two copies. These alleles can be identified through genetic testing.
Lifestyle and environmental factors may also contribute to the development of Alzheimer's disease. Other risk factors include hearing loss, lower education level, smoking, poor diet, lack of exercise, depression and social isolation. Research suggests that a healthy diet, good sleep and regular exercise may help to protect against Alzheimer's disease. Mental stimulation and social activity have also been linked to better brain health.
Diagnosing Alzheimer’s disease can pose some challenges. The early signs of Alzheimer’s disease can be mistaken for normal ageing, so until symptoms get more severe and start to affect our daily lives, we often do not notice them. It may take quite a long time, even months or years, before a definitive diagnosis is made. The earlier Alzheimer’s is detected and diagnosed, the better, as it provides an opportunity to implement lifestyle changes which may lead to better outcomes.
Diagnosis of Alzheimer’s disease involves a combination of tests including cognitive tests conducted by a doctor or a psychologist, as well as physical examinations, blood tests and imaging. The cognitive tests are designed to measure various aspects including memory, concentration, communication and orientation. However, these tests may not always be accurate, as some of the results can be subjective and influenced by factors such as language, educational level and cultural biases.
Imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), may be used to support the diagnosis of Alzheimer’s disease or to rule out other conditions. They provide information about the structure and function of the brain tissue. A special type of scan known as amyloid PET can detect amyloid deposits in the brain.
Another test, cerebrospinal fluid (CSF) analysis, involves the collection of a small amount of fluid that cushions the brain (CSF) through a minimally invasive procedure known as lumbar puncture, or spinal tap. Levels of specific biomarkers in the CSF, such as beta-amyloid and tau are measured. Low levels of beta-amyloid and raised levels of tau can be predictive of Alzheimer’s disease.
Currently, newer and less invasive tests are being developed that could provide additional information to support an earlier diagnosis. However, their accuracy and reliability is still being assessed so they are not currently recommended as a replacement for CSF biomarkers or amyloid imaging. 
Alzheimer's disease progresses in stages, but everyone experiences it differently. Knowing the stages can help the doctors and family members decide how to care for the people living with Alzheimer's disease.
Preclinical or Presymptomatic stage:
This is the early stage of the disease where a person doesn't show any symptoms, but lab tests can indicate they have the disease. Doctors can use certain biomarkers like levels of tau and amyloid in the person's CSF to diagnose Alzheimer's disease.
Mild cognitive impairment (MCI):
In this stage, a person starts to have trouble with their memory or other thinking abilities, but can still do most things they did before, like work, continue with hobbies and socialize with friends.
Mild Alzheimer’s disease:
Signs of mild Alzheimer’s disease include:
At the moment, there is no cure for Alzheimer's disease. But there are some promising treatment options that help slow down the disease and manage its symptoms by targeting beta-amyloid. However, it must be noted that these options are currently available in only certain locations.
Medicines that treat symptoms
These drugs cannot cure Alzheimer's disease or prevent damage to the brain cells, but they can help reduce or stabilize the symptoms of the disease for a limited time.
Supportive Therapies and Activities
Alongside medication, other therapies, activities and caregiver support are equally crucial to promote a better quality of life for those living with the disease.
They include group activities designed to improve memory (‘cognitive stimulation therapy’), working to achieve a goal such as learning to do an everyday task (‘cognitive rehabilitation’), and ‘life story’ work where the persons living with Alzheimer’s disease talks about or does activities based on events from their past.
Different medical professionals might be involved in caring for a person living with Alzheimer’s disease, including the family doctor, a psychiatrist or neurologist, geriatricians, specialist nurses, occupational therapists and psychologists.
Scientists are working to look into different aspects of the disease to find new ways to help people with Alzheimer's disease.
Most research focuses on new drugs that can help people with Alzheimer's disease by targeting specific changes that happen in the brain when someone has the disease. These changes include the build-up of specific proteins, inflammation in the brain, changes in metabolism, and more. By focusing on these targets, scientists hope to make treatments that can slow down or even stop the disease from getting worse.
As researchers learn more about Alzheimer’s disease, clinical trials are set up to look at potential new treatments.
If you would like to know more about Roche sponsored clinical trials or are interested in taking part in a clinical trial, speak to your doctor or visit the Roche ForPatients clinical trials page https://forpatients.roche.com/
Smart trial design can benefit everyone!
A comprehensive report has been developed to capture the experiences of people living with Alzheimer’s disease and their care. The report highlights the importance of early and inclusive collaboration between a trial’s sponsors and the Alzheimer’s community.
Co-signed and endorsed by eight patient organizations from across the world, the resource is freely available under a Creative Commons license and is aimed at those involved in trial design, people participating in trials and the wider Alzheimer’s community.
The core of this report includes practical solutions to help make clinical trials a more positive experience.