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Why Early Diagnosis Is Better for Alzheimer’s Patients
nutritional intake, weight loss, increased side effects due to mistakes The lack of a diagnosis of probable or definitive AD can have
in medication use and reduced quality of life. The physician could even potentially deleterious consequences for the patient, as disease
be held responsible for any possible problems. Furthermore, the progression can lead to several problems, particularly in those with
development of AD has been shown to follow a predictable pattern, advanced stages of the disease with a low cognitive function score,
with the changes taking place years before the onset of clinical e.g. an MMSE score <15. Such a low score has implications for the
symptoms.
5,6
These findings, plus the knowledge that many forms of patient’s safety. Both the Réseau sur la maladie d’Alzheimer
the disease progress slowly, suggest that early diagnosis and Français (REAL.FR) study
17
and the Impact of Cholinergic Treatment
subsequent intervention would allow an opportunity to achieve a Use (ICTUS) study
18
observed that more than 19% of patients with
better quality of life for the patient, family members and care-givers for AD live alone. This observation suggests a greater chance of
a longer period of time. In view of these issues, it seems valid to make patients with cognitive impairment experiencing medication
the diagnosis of AD as early as possible as it would enable better compliance issues and/or making mistakes with medications. This
management of the disease through pharmacological or non- in turn can lead to increased risks of side effects or aggravation of
pharmacological care. The progress of patients and any complications co-existing diseases when treatments are not taken. Memory loss
could also then be monitored by long-term follow-up, with appropriate is one of the most common symptoms of AD and has a significant
early assistance such as defined in the Specific Care and Assistance impact on the daily routine of a patient. Memory loss will also affect
Plan for Alzheimer’s Disease (PLASA) study.
7
The oldest AD sufferers a patient’s ability to manage personal and financial activities. AD
are expected to be prone to the greatest problems and should be could also have an impact on the nutritional intake of the affected
given all the help needed as soon as possible. person due to difficulties in carrying out shopping and cooking
activities, which have been linked to a poor Instrumental Activities
Diagnostic Criteria for Alzheimer’s Disease of Daily Living scale (IADL) score. AD could also have wider
Diagnosis of AD is based on the prevailing criteria set out by either the implications; for example, in cases where the patient is also a
National Institute of Neurological Disorders and Stroke–Alzheimer care-giver with responsibilities for a partner or family member who
Disease and Related Disorders (NINDS-ADRDA) working group,
8
or the also has health issues, AD may have a negative impact on the
American Psychiatric Association’s Diagnostic and Statistical Manual of provision of care. Advancing AD could also have a significant
Mental Disorders, 4th edition (DSM-IV-TR).
9
The diagnostic process negative impact on the care-giver, as deteriorating disease leads to
consists of two steps: initial identification of a dementia component a decrease in cognitive function of the patient and increased
followed by the application of criteria based on the clinical features of dependence on the care-giver.
the AD phenotype. In recent years, understanding of the biological basis
of AD has greatly improved and distinctive biomarkers of the disease Understanding the Importance
have been identified. These biomarkers include structural brain of an Earlier Diagnosis
changes visible on magnetic resonance imaging (MRI),
10
molecular Increasing evidence shows that AD progresses slowly during the
neuroimaging changes seen with positron emission tomography (PET)
11
early phase of the disease and that the disease evolves along a
and changes in cerebrospinal fluid biomarkers.
12
This progress in the predictable pattern of progression in the brain,
5,6
with the molecular
elucidation of the development of AD and identification of biomarkers pathomechanisms of AD becoming active many years before
of disease has led to the proposal of revised diagnostic criteria for AD.
13
neurons start dying and clinical symptoms appear.
19
Since there
These criteria aim to include both the earliest stages of disease, i.e. would be a lower burden of amyloid and hyperphosphorylated tau,
before confirmed dementia, and the complete range of disease stages. little or no deterioration in cognitive function in the early stages of
The core diagnostic criteria focus on the presence of early and the disease and a slow rate of disease progression, an earlier
significant episodic memory impairment. This should be complemented diagnosis followed by symptomatic or disease-modifying therapy
by the presence of at least one abnormal biomarker among structural could potentially be an effective strategy to help maintain a good
neuroimaging with MRI, molecular neuroimaging with PET and quality of life for patients, family members and care-givers. The most
cerebrospinal fluid analysis of amyloid or tau proteins. commonly used agents for early AD are the cholinesterase inhibitors,
including donepezil, rivastigmine and galantamine, which have been
Issues Associated with a Lack of Diagnosis shown to improve cognitive and global function in some patients.
Some physicians and other health professionals do not feel that
diagnosing AD is necessary due to the absence of any cure and the The early diagnostic approach has also provided primary care
stress related to diagnosis. According to this school of thought, a physicians with an opportunity to offer early psychosocial support
diagnosis would not be too useful as it would lead to fear and directly to individuals affected by AD. Psychosocial support can be
emotional distress for patients, serving only to compound the offered to early-stage groups, and the opportunity to share
patient’s misery of knowing they have the disease yet knowing there experiences and increased social support have been reported among
is no curative agent available. However, the counter-argument is that the benefits of such an approach.
20
While there are few trained
this assumption is not valid, as many patients exhibit a great desire professionals and a lack of psychosocial support groups, data indicate
for an early diagnosis, with up to 80% of older adults wishing to know that psychotherapy of early-stage individuals could help manage the
as early as possible whether they have probable or definitive AD.
14,15
A disease and reduce depression,
21
and such an approach should be
recent examination of short-term changes in depression and anxiety considered in the future.
after receiving a dementia diagnosis, using a 15-item Geriatric
Depression Scale and a 20-item ‘state’ version of the State–Trait Patients with AD have low functional disability and relatively good
Anxiety Inventory, noted that no significant changes in depression cognitive function in the early stages. Therefore, these patients can be
occurred in individuals or their companions, regardless of diagnostic involved in treatment planning, expressing opinions and desires
outcome or dementia severity.
16
regarding how to improve and maintain quality of life.
22
Indeed,
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