Dementia and Cognitive Decline: Understanding Alzheimer's and Other Forms

This article is general information published by the practice of Dr. Sholeh Toobaei, Specialist Psychiatrist, Dubai. It has not yet been individually reviewed by a clinician and is not a substitute for personal medical advice. Published: 1 September 2026.

Scope: This article is general information about dementia. It is not a diagnosis or treatment plan. If you or a loved one is experiencing cognitive changes, a professional assessment can help.

The distinction that matters

There is a critical distinction between normal age-related cognitive changes and dementia. This distinction matters because normal ageing is universal and harmless, while dementia is a medical condition that requires evaluation, management, and support.

Normal ageing. Forgetting names occasionally, misplacing your keys, needing a moment to recall a word, making an occasional poor decision. These are normal. They do not interfere with daily life. They are not progressive.

Dementia. Forgetting the names of close family members, getting lost in familiar places, being unable to manage medications or finances, repeating the same question within minutes, losing the ability to perform familiar tasks. These are not normal. They are progressive. They interfere with daily life.

The word "dementia" describes a group of symptoms, not a single disease. It refers to a significant decline in cognitive function that interferes with daily life and independence. The underlying cause can vary enormously.

The main types of dementia

Alzheimer's disease. The most common form, accounting for 60–80% of cases. It is characterised by two pathological changes in the brain: amyloid plaques (clusters of protein fragments that build up between nerve cells) and neurofibrillary tangles (twisted fibres of tau protein that build up inside cells). These disrupt communication between nerve cells and eventually cause cell death. Alzheimer's typically begins with memory impairment — difficulty forming new memories — and progresses to involve language, reasoning, behaviour, and eventually basic bodily functions. The typical course is 8–10 years, but some people live 20 years or more.

Vascular dementia. The second most common form. It is caused by reduced blood flow to the brain, often from small, unrecognised strokes (lacunar infarcts) or chronic small vessel disease. The hallmark is problems with planning, organisation, and processing speed. Memory may be less affected than in Alzheimer's. The course can be stepwise — periods of stability followed by sudden declines corresponding to new vascular events. Risk factors include high blood pressure, diabetes, high cholesterol, and smoking.

Lewy body dementia. Characterised by abnormal protein deposits (Lewy bodies) in the brain. The hallmark triad: cognitive fluctuations (alertness and cognition vary significantly from hour to hour and day to day), visual hallucinations (often detailed and well-formed), and parkinsonian motor symptoms (tremor, stiffness, slow movement). People with Lewy body dementia are unusually sensitive to antipsychotic medications, which can cause severe worsening — this is an important clinical detail. The course is typically 5–7 years.

Frontotemporal dementia. Affects the frontal and temporal lobes of the brain, which control personality, behaviour, and language. The hallmark is a change in personality and behaviour — loss of inhibition, apathy, disinhibition, loss of empathy, compulsive behaviours, dietary changes (particularly craving sweets). Memory is relatively preserved in early stages. It typically begins earlier than Alzheimer's, in the 50s or early 60s. There are subtypes that primarily affect language (primary progressive aphasia) or movement (associated with Parkinson's disease or motor neurone disease).

Mixed dementia. Many older adults have more than one type. Alzheimer's plus vascular dementia is the most common combination. Mixed dementia can make the presentation and progression less typical of any single type.

Reversible causes of cognitive impairment

Not all cognitive decline is due to progressive dementia. Several conditions cause cognitive impairment that is potentially reversible:

Medication side effects. Many commonly prescribed medications — particularly anticholinergic drugs (some antihistamines, bladder control medications, antidepressants), benzodiazepines, opioid pain medications, and certain blood pressure medications — can cause significant cognitive impairment. Reviewing medications is an essential first step in evaluating cognitive decline.

Vitamin deficiencies. Vitamin B12 deficiency is a well-recognised cause of cognitive impairment. Vitamin D deficiency is also associated with cognitive decline. Both are common in older adults and both are treatable.

Thyroid disorders. Both hypothyroidism and hyperthyroidism can cause cognitive symptoms — "brain fog," memory problems, slowed thinking. Thyroid function is routinely checked in cognitive assessment.

Depression. "Pseudodementia" — cognitive slowing and memory problems caused by depression — can mimic dementia. The key difference is that cognitive symptoms in depression tend to be fluctuating and may improve with treatment of the depression.

Normal pressure hydrocephalus. A build-up of cerebrospinal fluid in the brain that causes a classic triad: cognitive impairment, urinary incontinence, and gait disturbance (magnetic gait — feet seem stuck to the floor). This is surgically treatable with a shunt.

Infection and metabolic disturbance. Urinary tract infections (UTIs), pneumonia, dehydration, electrolyte imbalances, and organ failure can all cause acute or subacute cognitive changes in older adults. These require immediate medical evaluation.

Delirium: the emergency

Delirium is an acute (hours to days), often reversible state of confusion caused by a medical problem. It is characterised by:

Acute onset. The change develops over hours or days. Fluctuating consciousness. The person is alternately drowsy and alert, coherent and confused. Inattention. The person cannot focus, sustain, or shift attention. Disorganised thinking. Speech is incoherent or irrelevant. Altered level of awareness. Hyperactive (agitated, restless), hypoactive (drowsy, withdrawn), or mixed.

Delirium is a medical emergency. It is most commonly caused by infection (especially UTI or pneumonia), medication changes, dehydration, or metabolic disturbance. If an older person suddenly becomes confused, agitated, or withdrawn, this is delirium until proven otherwise, and it requires immediate medical evaluation.

Early warning signs

Recognising the early signs of dementia is critical because early diagnosis allows for:

Treatment of reversible causes Planning and preparation for the future Access to treatments that may slow progression Support for the person and their family

Common early signs:

Memory loss that disrupts daily life. Forgetting recently learned information, important dates or events, asking for the same information repeatedly. Difficulty with familiar tasks. Trouble driving to a familiar location, managing a budget, or remembering the rules of a favourite game. Problems with language. Trouble following or joining a conversation. Stopping mid-conversation and having no idea how to continue. Repeating things. Disorientation. Getting lost in familiar places. Losing track of dates, seasons, and the passage of time. Forgetting where they are or how they got there. Poor judgment. Changes in judgment or decision-making. Falling for scams. Giving large sums of money to telemarketers. Neglecting personal grooming. Withdrawal. Pulling away from work, social activities, or hobbies that were previously enjoyed. Mood and personality changes. Becoming confused, suspicious, depressed, fearful, or anxious. Getting easily upset at home, at work, with friends, or in places where they are out of their comfort zone.

Diagnosis

There is no single test for dementia. Diagnosis is based on:

Clinical history. A detailed account of the person's symptoms, their progression, and their impact on daily life. The most informative history often comes from a family member or close friend, because the person with dementia may lack insight into their condition.

Cognitive testing. Brief screening tests like the MMSE (Mini-Mental State Examination) or MoCA (Montreal Cognitive Assessment) assess memory, language, attention, visuospatial skills, and executive function. These are screening tools, not diagnostic tools.

Blood tests. To rule out reversible causes: thyroid function, vitamin B12, vitamin D, complete blood count, metabolic panel.

Brain imaging. CT or MRI scan to look for structural changes, strokes, tumours, or other abnormalities.

Specialist referral. In complex or atypical cases, referral to a neurologist or geriatric psychiatrist for comprehensive evaluation.

Treatment and management

There is currently no cure for most forms of dementia. However, several approaches can help manage symptoms and, in some cases, slow progression:

Medications for Alzheimer's disease. Cholinesterase inhibitors (donepezil, rivastigmine, galantamine) can provide modest symptomatic benefit for mild-to-moderate Alzheimer's. Memantine (an NMDA receptor antagonist) is used for moderate-to-severe Alzheimer's. A newer class of medications — amyloid-modifying antibodies (like lecanemab) — target the underlying amyloid pathology and may slow decline in early Alzheimer's, but they carry significant risks and are not widely available.

Medications for behavioural symptoms. Depression, anxiety, agitation, and psychosis in dementia can often be managed with medication. SSRIs are typically first-line for depression and anxiety. Antipsychotic medications are used cautiously in dementia because they carry an increased risk of stroke and death in older adults with dementia.

Non-pharmacological approaches. These are often the most important part of management: structured daily routines, meaningful activity, physical exercise, music therapy, reminiscence therapy, creating a safe and familiar environment, reducing sensory overload, and maintaining social contact.

Vascular risk management. For vascular dementia and mixed dementia, managing blood pressure, diabetes, cholesterol, and other vascular risk factors is the most important intervention. What is good for the heart is good for the brain.

Supporting a person with dementia

For families, caring for someone with dementia is one of the most emotionally demanding experiences a person can face:

Learn about the condition. Understanding what the person is experiencing — not just intellectually, but emotionally — makes their behaviour more comprehensible and less personally distressing.

Adapt your communication. Speak slowly and clearly. Use short sentences. One question at a time. Do not correct or argue. If the person says something that is factually wrong but not distressing, let it go. The emotional truth matters more than the factual truth.

Maintain routine. Predictability reduces anxiety and confusion. A consistent daily schedule — regular mealtimes, regular activities, regular bedtimes — provides structure that the person's declining cognitive capacity can no longer create for themselves.

Ensure safety. Remove hazards. Install locks or alarms if wandering is a risk. Supervise driving. Manage medications. These practical steps are necessary, not excessive.

Look after yourself. Caregiver burnout is real and dangerous. Caring for someone with dementia is a marathon, not a sprint. Respite care, caregiver support groups, and maintaining your own health and social connections are not luxuries — they are essential components of effective caregiving.

The Dubai context

Dementia care in Dubai has specific considerations:

Cultural norms around ageing. In many cultures represented in Dubai's population, caring for older family members at home is the expected norm. Institutional care is often viewed as a last resort or even a failure. This creates enormous pressure on family caregivers, particularly when professional care would benefit both the person with dementia and the family.

Multicultural complexity. Dementia can present differently across cultures — the way symptoms are reported, the stigma associated with cognitive decline, the willingness to seek medical evaluation. A clinician in Dubai who understands these cultural differences is essential.

Access to specialist care. Neurologists and geriatric psychiatrists with expertise in dementia are available in Dubai but represent a smaller subspecialty than adult psychiatry. Early diagnosis requires finding the right specialist.

Live-in caregivers. Many families in Dubai employ live-in caregivers from South Asia or the Philippines. While this provides invaluable support, caregivers should be educated about dementia to understand that challenging behaviours are symptoms of the disease, not deliberate acts.

When should I seek help?

If you or someone you know is experiencing memory problems, confusion, difficulty with familiar tasks, or other cognitive changes that are affecting daily life — seek a professional assessment. Early diagnosis matters. Some causes of cognitive decline are reversible, and for progressive forms, early diagnosis allows for planning, treatment, and support that improve quality of life.

Seek urgent help — call 999 (police) or 998 (ambulance) in the UAE, or go to the nearest emergency department — if an older person has become suddenly confused, agitated, or withdrawn (possible delirium), if they are a danger to themselves or others, or if you are in any way concerned about their immediate safety. For non-urgent enquiries, use the appointment request form on this website. This practice does not operate a monitored telephone line, and a message sent through the form may not be read straight away.