Alzheimer's disease: For people living with AD
Alzheimer’s disease begins to form around 20 years before memory loss or other symptoms develop. However, in the absence of pathology specific biomarkers, AD is not accurately diagnosed in symptomatic individuals, especially if they present with early symptomatic disease. According to the Alzheimer's Association, 85% of people would want to know early if they had the disease.1
An early and accurate diagnosis is crucial for patients, caregivers and physicians, as it can provide clarity and new treatment options.2-3
Clinical trials and other studies showed that up to 30% of individuals who meet the criteria for clinical Alzheimer’s dementia based on symptoms did not have Alzheimer’s-related brain changes.1 By utilizing biomarkers to support Alzheimer’s diagnosis, especially in early disease stages, the accuracy of clinical diagnosis is expected to increase significantly.3 The need for a more precise diagnosis is now.
Definitions
What are biomarkers?
Biomarkers are biological changes that can be measured to indicate the presence or absence of a disease or the risk of developing a disease. The biomarkers most characteristic to Alzheimer’s are abnormal amyloid beta and tau proteins which accumulate in the brain and are present in the cerebrospinal fluid (CSF) and blood.
Therefore, changes in these proteins can be visualized by imaging the brain with scanning techniques, or can be measured in the CSF and blood1,2 using laboratory tests.
For example, the Elecsys CSF ratio assays are FDA cleared laboratory tests designed to detect the level of amyloid-beta protein (1-42) (Abeta42), phosphorylated tau protein 181 (pTau181) and total Tau protein (tTau). The results of these tests are intended to be interpreted by the physicians along with other clinical diagnostic evaluations to support AD diagnosis.4
What is cerebrospinal fluid?
CSF is a fluid that surrounds and protects the brain and spinal cord. CSF contains the abnormal amyloid and tau proteins associated with Alzheimer’s disease (AD). In case of cognitive issues and suspicion of AD, measuring the levels of these proteins from CSF helps with the AD diagnosis process. To collect CSF for testing these specific proteins, a lumbar puncture (spinal tap) is needed.1,2
Early diagnosis of Alzheimer’s is key
The progression of AD occurs along a continuum, starting with preclinical neuropathological changes, and then progresses to mild cognitive decline that can advance to demetia stages where it interferes with daily life, independence and function. The new amyloid targeting therapies and diagnostic tests have made possible the early detection of amyloid pathology and, in clinical context, early AD diagnosis and referal to therapy. As these therapies are effective in the early disease stages (i.e., MCI and mild dementia), early detection and diagnosis are crucial to timely intervention:1-4
Mild cognitive impairment due to Alzheimer’s
Mild symptoms but independence is maintained. Diagnosing people at the early, MCI stage, rather than the dementia stage, will allow healthcare professionals to intervene sooner — and at a stage that makes a great difference in people’s lives.
Preclinical AD
Evidence of Alzheimer's pathology, but no symptoms
MCI due to AD
Mild symptoms but independence is maintained
Mild AD dementia
Symptoms interfere with more complex activities and independence is no longer maintained
Moderate to severe AD dementia
Cognitive and functional symptoms interfere with many to most activities and lead to progressive loss of independence
Understanding signs of normal aging vs. Alzheimer’s disease
View full tableUnderstanding signs of normal aging vs. Alzheimer’s disease
AD affects memory, behavior, problem-solving and daily activities. It’s a medical condition — not part of normal aging — and one of the biggest public health challenges of our time. View the table below to compare normal signs of aging and Alzheimer’s.
AD affects memory, behavior, problem-solving and daily activities. It’s a medical condition — not part of normal aging — and one of the biggest public health challenges of our time. View the table below to compare normal signs of aging and Alzheimer’s.
Normal aging |
Alzheimer's |
| Occasionally making poor decisions | Frequently making poor decisions and having poor judgment |
| Occasional errors with managing finances | Trouble keeping track of bills and concentrating |
| Occasionally needing help with daily tasks | Difficulty completing daily tasks |
| Getting confused about what day of the week it is, but remembering it later | Confusion about place and time, including losing track of dates and sometimes forgetting where you are and how you got there |
| Having difficulty finding the right word once in awhile | Struggling with vocabulary, as well as trouble joining or following a conversation |
| Occasionally misplacing items, but having the ability to retrace steps and find them | Misplacing items, but losing the ability to retrace steps to find them |
| Lack of interest in social and familial obligations from time to time | Withdrawal from work, hobbies and social obligations |
| Irritability when a routine is disrupted | Changes in personality and mood, including getting easily upset |
| Changes with vision, which can be related to cataracts | Difficulty understanding visual images and spatial relationships |
| Forgetting appointment or names once in a while, but remembering them afterwards | Forgetting recently learned information and asking for the information repeatedly or relying on others for things previously handled on one's own |
Jeff’s Story: An Alzheimer’s Diagnosis
Jeff’s Story: Being diagnosed with Alzheimer’s
After a series of misdiagnoses, he’s now battling cognitive decline with grace and courage.
Read his story
References
- Alzheimer’s Association. 2024 Alzheimer’s Disease Facts and Figures. Alzheimer's Dement 2024;20(5).
- Alzheimer’s Association. Accessed July 1, 2023.
- Sabbagh MN, Lue LF, Fayard D, Shi J. Increasing Precision of Clinical Diagnosis of Alzheimer's Disease Using a Combined Algorithm Incorporating Clinical and Novel Biomarker Data. Neurol Ther. 2017 Jul;6(Suppl 1):83-95
- Elecsys® Method Sheets: ms_08846634501; ms_08821909501; ms_08846715501; ms_08846693501; ms_08821941501.