The greatest pleasures in life are often the simplest: laughing over childhood memories with an old friend. Shopping for the family dinner. Planning the next holiday over a cup of coffee. Chatting online with relatives who live in other cities, other countries.

These are the very things that Alzheimer’s disease steals away and never gives back. Alzheimer’s can progress gradually or quickly, but patients inevitably lose their memory, their ability to think, to plan, to recognise even those closest to them. Their entire identity is essentially lost both to the world and to themselves.

Helen Rochford-Brennan, Chairperson of the European Working Group of People with Dementia, speaks of the “lonely, bleak drive home from the doctor’s office” after learning she had Early-onset Alzheimer’s disease.

“I had a wonderful career, an active life, and it was almost impossible to accept that all that was in the past and that life would never be as it was,” she says.

Affecting more than 46 million people around the world, dementia stands as one of the 21st century’s most challenging health problems. The number of people with dementia is expected to double every 20 years – meaning that by 2050 more than 135 million will be affected.1 Alzheimer’s disease (AD) is dementia’s leading cause, usually striking older adults but also occurring in people as young as their 30s or 40s.2

Healthcare systems are already having serious difficulties coping with the current incidence and may be overwhelmed in just a decade or two by the sheer number of Alzheimer’s patients needing care. According to Alzheimer’s Disease International, around 40% of the costs of dementia care worldwide are paid by “informal” sources – which, in many cases, means the patient’s family.

Diagnosis dilemma

Currently, the diagnosis of AD is largely based on clinical symptoms, including cognitive testing, with a significant number of patients diagnosed when their disease has already advanced. Symptoms usually emerge after the age of 60 although people with certain rare genetic mutations may develop the disease earlier. A diagnosis of AD based on cognitive measures alone is only correct in 70-80% of cases. Even with imaging studies such as computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET), the diagnosis might not be conclusive.3

“This means that up to 25% of families have been told their loved one has Alzheimer’s disease and they don’t,” says Dr Jeffrey Cummings, Cleveland Clinic Lou Ruvo Center for Brain Health (Cleveland, Ohio). “Which also means that up to 25% of people participating in some type of clinical trial don’t actually have Alzheimer’s disease.”

AD1

New tests have been developed that are based on biomarkers found in cerebrospinal fluid (CSF), the fluid found in the spinal column and around the brain. CSF acts as a cushion for the spine and brain, brings needed supplies from blood, and takes away the brain cells’ waste products.

This fluid can contain peptides that have been closely linked to Alzheimer’s disease: amyloid-beta (Abeta) and Tau (neurofibrillary tangles). In a healthy brain, these Abeta peptides are broken down and eliminated; in a patient with Alzheimer’s, they bunch together and form hard, insoluble plaques. The Tau neurofibrillary tangles – twisted, insoluble fibers made up of the Tau protein forming structures called microtubules – normally transport nutrients and other important substances from one nerve cell to another. With Alzheimer’s, the protein is abnormal and the microtubules are unstable. The new tests for Abeta and Tau can provide clinicians with critical information to help them make a faster, accurate diagnosis.4

Biomarkers are of enormous use in the diagnosis of AD. They are objective measures, they are reproducible and they are independent of the clinician’s judgment.
Dr Jeffrey Cummings, Cleveland Clinic Lou Ruvo Center for Brain Health

Moving forward

With no cure for Alzheimer’s, is there really any point to being tested and diagnosed with the disease? Experts answer with a resounding yes, for several reasons. An accurate diagnosis made as early as possible is “tremendously important,” Dr Cummings observes.

“We know that patients are being diagnosed far too late in the course of their clinical disease,” he says.

Although many studies of promising drugs have had negative results, researchers were able to learn more about this devastating disease and gain deeper understanding of how to design clinical trials and identify which patients should be included. For example, scientists now understand that the treatment approach for patients in early stages of the disease should be different from the approach for those in later stages.

We want patients identified early, so that we can start therapy. We can get them into clinical trials and, most of all, we can help them and their families understand what this disease is about.
Dr Jeffrey Cummings

And what is clearly evident is that, as with cancer, detecting and diagnosing Alzheimer’s early is vitally important. The earlier the treatment starts, the more likely it is to have a positive effect on how the disease progresses. For clinical trials, knowing that the participating patients really have Alzheimer’s -- and not another form of dementia -- gives more confidence in the results.

“There are treatments for Alzheimer’s that improve the symptoms and that often help people function better for a longer period of time,” says Rachelle Doody, MD, Global Head of Neurodegeneration at Roche. “And one reason for having an early diagnosis of Alzheimer’s disease is the opportunity to participate in clinical trials that may benefit society and the future, and it may also benefit the patients if these treatments are shown to be effective.”

Stepping out of the shadows

For people with Alzheimer’s disease, like Helen, there is real value in raising awareness about the importance of diagnosis and in learning about the research and clinical trials available that may lead to effective treatments that could transform Alzheimer’s disease.

“With the right diagnosis and support, we can live with this condition,” she said. “We are seeing dementia-inclusive communities thanks to advocacy work. And as an advocate, I am hoping to create a better quality of life that we can all benefit from. No, we do not have a cure right now. But we do have hope.”

    

References

  1. Alzheimer’s Disease International. World Alzheimer Report 2015 [Internet; cited 2015] Available from: https://www.alz.co.uk/research/WorldAlzheimerReport2015-sheet.pdf
  2. Alzheimer’s Association. Younger/Early Onset Alzheimer’s [Internet; cited 2018]. Available from: https://www.alz.org/alzheimers-dementia/what-is-alzheimers/younger-early-onset
  3. Gaugler JE, et al.Characteristics of patients misdiagnosed with Alzheimer’s disease and their medication use: an analysis of the NACC-UDS database. BMC Geriatrics. 2013;13;137. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3878261/
  4. Alzheimer’s Society. Dementia Update UK. [Internet; cited November 2014] Available from: https://www.alzheimers.org.uk/sites/default/files/migrate/downloads/dementia_uk_update.pdf

Tags: Patients, Diagnostics