Alzheimer’s Disease Awareness Month: How is it diagnosed and why is early detection important?
The symptoms of Alzheimer’s and other dementias worsen over time, but the rate at which the disease progresses varies. In the early stage of Alzheimer’s, for example, a person may function independently, still drive, work, and be part of social activities. Despite this, the person may notice memory lapses, such as forgetting familiar words or the location of everyday objects. According to health experts, the earlier that Alzheimer’s and other dementias are diagnosed, the sooner people and their families can receive information, care and support. So how is the disease diagnosed?
Assessing memory problems and other symptoms
It is best to see your doctor if you are worried about your memory or are having problems with planning and organizing, advise experts. A key component of a diagnostic assessment is self-reporting about symptoms, as well as the information that a close family member or friend can provide about symptoms and their impact on daily life.
During the medical checkup, the doctor will review your overall medical history, including psychiatric history, past medical problems and the use of prescription and over-the-counter medicines. He or she will want to know whether you have impaired memory or thinking skills, whether there have been changes in behavior or personality, and if a person can carry out daily activities, among others. The doctor will also ask about key medical conditions affecting other family members, including whether they may have had Alzheimer’s disease or other dementias.
To diagnose Alzheimer’s dementia, doctors conduct tests of memory, problem-solving, attention, counting and language. They also perform multiple tests to rule out other possible causes of impairment. Blood tests, for example, may be done to determine if a person has other medical conditions that may be causing or contributing to the symptoms. Neurological exams and mental status tests, may also be conducted. “There is no single diagnostic test that can determine if a person has Alzheimer’s disease. Physicians (often with the help of specialists such as neurologists, neuropsychologists, geriatricians, and geriatric psychiatrists) use a variety of approaches and tools to help make a diagnosis. Although physicians can almost always determine if a person has dementia, it may be difficult to identify the exact cause,” say scientists.
The physician may recommend brain imaging tests such as a CT (computed tomography) scan or an MRI (magnetic resonance imaging) scan. These tests may be repeated to give doctors information about how the person’s memory and other cognitive functions are changing over time. They can also help diagnose other causes of memory problems, such as stroke, tumor, Parkinson’s disease, sleep disturbances, side effects of medication, an infection, mild cognitive impairment or a non-Alzheimer’s dementia, including vascular dementia. Some of these conditions may be treatable and possibly reversible.
“A growing area of research is the development of devices to administer computer-based tests of thinking, learning, and memory, called cognitive tests. The US Food and Drug Administration (FDA) has cleared several computerized cognitive testing devices for marketing. These are the Cantab Mobile, Cognigram, Cognivue, Cognision and Automated Neuropsychological Assessment Metrics (ANAM) devices,” explains the Alzheimer’s Association. It adds, “In some circumstances, a doctor may use brain imaging tools to find out if the individual has high levels of beta-amyloid, a hallmark of Alzheimer’s; normal levels would suggest Alzheimer’s is not the cause of dementia.”
A positron emission tomography (PET) may also be suggested to rule out other possible causes for symptoms. It uses a low-level radioactive substance known as a tracer to detect substances in the body. There are different types of PET scans. Last year, a US study found that PET, a form of brain imaging that detects Alzheimer’s related plaques, significantly influenced clinical management of patients with mild cognitive impairment (MCI) and dementia.
The researchers found that in MCI patients with significant amyloid deposits, physicians were twice as likely to prescribe Alzheimer’s drugs after positive PET imaging. In those with dementia, prescriptions rose from 63% pre-PET to 91% following positive amyloid imaging. A number of patients with MCI and dementia and negative amyloid imaging were taken off Alzheimer's medications, suggesting an improvement in appropriate drug prescribing for Alzheimer’s patients.
It may take several appointments and tests over many months before a diagnosis of Alzheimer’s disease can be confirmed. It may also be diagnosed more quickly than this. However, health experts emphasize that it takes time to adapt to a diagnosis of dementia, for both the patient and his or her family. Some people find it helpful to seek information and plan for the future, but others may need a longer period to process the news, they add.
“When a doctor tells you and your family members about an Alzheimer’s diagnosis, he or she will help you understand Alzheimer’s dementia, answer questions, and explain what to expect. Doctors will explain what capacities are preserved and how to limit future disabilities, and look to keep you as healthy and safe as possible with the least disruption in your daily activities,” explains the Mayo Clinic.
How is it beneficial?
Early, accurate diagnosis is beneficial for several reasons. Beginning treatment early in the disease process may help preserve daily functioning for some time, even though the underlying Alzheimer’s process cannot be stopped or reversed.
Besides access to available symptomatic treatments and interventions, a formal diagnosis allows people living with Alzheimer’s to build a care team, participate in support services and potentially enroll in clinical trials. Besides, an early diagnosis helps people with Alzheimer’s and their families plan for the future, take care of financial and legal matters, address potential safety issues, and learn about living arrangements. Patients and their caregivers can set systems in place to better manage medications, receive counseling, and address the challenges of other chronic conditions.
A report suggests that nearly 90% of Americans say that if they were exhibiting confusion and memory loss, they would want to know if the cause of the symptoms was Alzheimer’s disease. Yet, over half of the people aged 45 and older with subjective cognitive decline have not talked with a healthcare provider about their questions, concerns, and fears. Among those whose memory problems were creating functional difficulties, 42% had not shared these issues with a provider.
Researchers say that for timely and accurate early detection to occur — and subsequent diagnosis and disclosure awareness — people must feel comfortable discussing symptoms and concerns with their healthcare providers. This requires addressing barriers such as low public awareness of the early signs of Alzheimer’s, emotional distress of Alzheimer’s and other dementias on family members, and misperceptions about Alzheimer’s and other dementias. “Public health should consider addressing obstacles faced by physicians such as low recognition of the signs of cognitive impairment; confusion with conditions that may mimic dementia (including delirium, certain vitamin deficiencies, and depression); limited education or training on dementia care; concerns about stigma and the usefulness of an early diagnosis; lack of time; and difficulty talking about dementia or disclosing a diagnosis,” recommend health experts.