3.1. Explain how dementia is diagnosed

This guide will help you answer 3.1. Explain how dementia is diagnosed.

Diagnosing dementia can be challenging as it is not a single condition but a collective term for symptoms caused by different diseases affecting the brain. An accurate diagnosis is essential to ensure the individual receives the correct care, support, and treatment. The diagnostic process involves multiple steps, including assessments by healthcare professionals, medical tests, and input from the individual and their family.

Recognising Early Symptoms

The process of diagnosing dementia often begins with recognising signs and symptoms. These may include:

• Memory problems, such as forgetting recent events or conversations.
• Difficulty with language or communication.
• Changes in mood, behaviour, or personality.
• Problems with reasoning, problem-solving, or planning.
• Disorientation to time, place, or people.

Many people first raise concerns with a GP (general practitioner) when these symptoms start to impact daily life.

Initial Assessment by a GP

The first step in the diagnostic process involves a GP conducting an initial health assessment. This usually includes:

• Medical History: The GP asks about the person’s symptoms, when they started, and how they are affecting daily life. They also explore any family history of dementia or neurological issues.
• Lifestyle Factors: The GP may ask about diet, exercise, alcohol use, smoking, and sleep patterns.
• Current Medications: Certain medications can cause side effects that mimic dementia symptoms, so these are reviewed.
• Mental Health History: Anxiety, stress, and depression can also cause memory problems, so these are considered.

The GP may involve close family members or carers in the discussion to gather further insight.

Physical Examination

A physical examination may be carried out to rule out other conditions that may cause similar symptoms. This may include checking for:

• Signs of vitamin deficiencies, such as vitamin B12 deficiency.
• Medical conditions like diabetes, thyroid disorders, or infections.
• Hearing or vision problems that might affect communication or memory.
• Signs of a stroke or cardiovascular disease, which can contribute to vascular dementia.

Blood tests might also be ordered to detect underlying medical issues that could explain the symptoms.

Cognitive and Memory Tests

To assess cognitive function, the GP may administer simple mental ability or memory tests. These are designed to evaluate thinking, reasoning, and memory skills. Common tests include:

• Clock Drawing Test: The individual is asked to draw a clock and set a specific time. This evaluates visual-spatial skills and problem-solving.
• Mini-Mental State Examination (MMSE): A standard test that checks memory, attention, language, and orientation.
• General Practitioner Assessment of Cognition (GPCOG): A quick screening test to assess memory and cognitive function.

These tests provide an indication of whether further investigation is necessary.

Referral to a Specialist

If dementia is suspected, the GP often refers the individual to a specialist. This might include:

• A neurologist, who specialises in brain disorders.
• A geriatrician, who focuses on health in older adults.
• A psychiatrist, especially if mental health issues are present.
• A memory clinic, staffed by a team of dementia specialists, including psychologists, nurses, and occupational therapists.

Specialist evaluations provide more in-depth testing and analysis to confirm a dementia diagnosis.

Advanced Cognitive and Neuropsychological Testing

Specialists may carry out detailed neuropsychological assessments to assess various areas of brain function. These tests examine:

• Memory (short-term and long-term).
• Concentration and attention span.
• Reasoning and problem-solving skills.
• Language abilities, including naming objects and understanding speech.

These tests are particularly helpful in identifying specific types of dementia, as they test the areas of the brain most likely to be affected.

Brain Scans and Imaging

Brain imaging is often used to identify changes in the brain that may indicate the presence of dementia. Common types of brain scans include:

• MRI (Magnetic Resonance Imaging): Provides detailed images of brain structures and can detect brain shrinkage or damage, particularly in Alzheimer’s disease or after a stroke.
• CT (Computed Tomography): Useful for identifying strokes, tumours, or significant structural changes in the brain that could affect cognitive function.
• PET (Positron Emission Tomography): Can detect patterns of brain activity and identify abnormal metabolic function associated with dementia.
• EEG (Electroencephalogram): Used to measure electrical activity in the brain, particularly in cases of suspected seizures or Creutzfeldt-Jakob disease (a rare type of dementia).

Brain scans not only help confirm a diagnosis but also help differentiate between types of dementia, as each affects the brain in different ways. For instance, vascular dementia may show evidence of strokes, while frontotemporal dementia may present with shrinkage in the front areas of the brain.

Laboratory Tests

In certain cases, lumbar puncture (spinal tap) tests might be performed to check cerebrospinal fluid for markers of conditions such as:

• Alzheimer’s disease (the presence of abnormal proteins, such as amyloid or tau).
• Infections or inflammatory conditions that might mimic dementia.

These tests are not always routine but may be used when the diagnosis is unclear or when rare forms of dementia are suspected.

Diagnostic Criteria

The diagnosing specialist uses internationally recognised diagnostic criteria to determine the presence of dementia. Examples include:

• DSM-5 (Diagnostic and Statistical Manual of Mental Disorders): Defines dementia as “major neurocognitive disorder” and outlines specific criteria for diagnosis.
• ICD-11 (International Classification of Diseases): Used globally to classify and diagnose medical conditions, including dementia.

These criteria focus on the severity of cognitive impairment, its impact on daily living, and the exclusion of diseases that might cause similar symptoms.

Differentiating Between Types of Dementia

An accurate diagnosis involves identifying the specific type of dementia affecting the individual. Key differentiators include:

• Alzheimer’s Disease: Marked by memory loss and brain shrinkage visible on scans.
• Vascular Dementia: Associated with strokes or reduced blood flow to the brain, often seen as small white areas on an MRI.
• Lewy Body Dementia: May cause hallucinations, Parkinsonism (movement problems), and fluctuating cognitive abilities.
• Frontotemporal Dementia: Often affects behaviour, emotion, and language before memory is impacted.

Each type has different treatments or care approaches, making this distinction crucial.

Involving the Individual and Family

Throughout the diagnostic process, input from the individual and their family or carers is essential. Family members can provide valuable information about changes in behaviour, communication, and abilities that the individual may not recognise or remember.

Additionally, it is important to communicate the diagnosis sensitively, providing clear explanations and answering any questions. This can be an emotional experience for everyone involved.

Outcome of the Diagnosis

Once a diagnosis is made, the healthcare team provides the individual and their family with a care plan. This may include:

• Information about the specific type of dementia and its progression.
• Recommendations for treatment, such as medications to manage symptoms.
• Referral to social services or support groups.
• Guidance on financial and legal planning, including lasting powers of attorney.

Early diagnosis allows the person and their loved ones to plan for the future and access available support services.

Final Thoughts

Diagnosing dementia involves a thorough process that includes clinical assessments, cognitive tests, brain imaging, and specialist evaluations. It ensures accurate identification of the condition and type of dementia, enabling appropriate care and treatment. Early diagnosis also empowers individuals and their families to understand the condition and prepare for its progression.