By Dr Ruchir Divatia
Consultant Neurologist
Jan 27, 2026
When it comes to memory loss and cognitive decline, the terms "dementia" and "alzheimer’s disease" are often used interchangeably. However, understanding the distinction between these two conditions is crucial for accurate diagnosis, effective treatment, and informed care planning. This comprehensive guide will help you know what sets them apart and how they're related.
Dementia is not a specific disease but rather an umbrella term that describes a group of symptoms affecting cognitive function. Think of dementia as a category, much like "heart disease" encompasses various cardiac conditions. When someone has dementia, they experience a decline in cognitive abilities severe enough to interfere with daily life and independent functioning.
People with dementia typically experience several cognitive impairments, including
The severity of these symptoms varies depending on the type of dementia and the stage of progression.
Alzheimer's disease is the most common cause of dementia, accounting for 60 to 80 per cent of all dementia cases. It's a specific, progressive brain disease that causes problems with memory, thinking, and behaviour. While all people with alzheimer's disease have dementia, not all people with dementia have alzheimer's disease.
Alzheimer's disease causes brain cells to die and brain tissue to shrink over time. Two abnormal protein structures are hallmarks of the disease: plaques (clusters of beta-amyloid protein) and tangles (twisted fibres of tau protein). These structures interfere with communication between nerve cells, leading to cell death, beginning in brain regions responsible for memory formation.
Alzheimer's typically progresses through three general stages
The relationship
The fundamental difference is that dementia is a syndrome—a collection of symptoms—while alzheimer's is a disease that causes dementia. You can think of it this way: dementia is the umbrella, and alzheimer's disease is the most common condition underneath it.
Other types of dementia
Besides alzheimer's disease, several other conditions cause dementia
Diagnosing dementia
Doctors diagnose dementia through a comprehensive evaluation that includes medical history, physical examination, laboratory tests, and assessment of cognitive changes. They look for impairment in at least two core cognitive functions, such as memory, communication, reasoning, or visual perception.
Diagnosing alzheimer's disease
Alzheimer's diagnosis involves similar tests but aims to rule out other causes of dementia. Doctors use brain imaging (MRI or CT scans), mental status tests, neurological examinations, and sometimes biomarker tests to detect alzheimer 's-specific changes. A definitive diagnosis can only be made through brain tissue examination after death, but doctors can diagnose "probable alzheimer's" with over 90 per cent accuracy using current methods.
Alzheimer's risk factors
Age is the greatest risk factor for alzheimer's, with most people diagnosed after age 65. Family history and genetics also play a role, particularly the APOE-e4 gene. However, having these risk factors doesn't guarantee someone will develop the disease.
Reducing dementia risk
While some risk factors like age and genetics cannot be changed, research suggests several lifestyle factors may reduce dementia risk
Current treatment options
There is currently no cure for alzheimer's disease or most other types of dementia, but treatments can help manage symptoms and improve quality of life. Medications like cholinesterase inhibitors and memantine may temporarily improve or stabilise cognitive symptoms. Recent medications targeting amyloid proteins show promise in slowing progression in early-stage alzheimer's.
Comprehensive care approach
Managing dementia requires a multifaceted approach that includes medication management, cognitive stimulation, physical activity, nutritional support, social engagement, and creating a safe environment. Equally important is safeguarding the physical and mental health of caregivers, as caring for someone with dementia can be emotionally and physically demanding. Ensuring caregivers receive adequate rest, emotional support, education, and access to healthcare services helps improve outcomes for both the patient and the caregiver.
When to seek help
If you or a loved one experiences persistent memory problems or cognitive changes that interfere with daily life, consult a healthcare provider. Early diagnosis offers several benefits, including access to treatment options, time to plan for the future, support services for caregivers, and the opportunity to participate in clinical trials.
Understanding the difference between dementia and alzheimer's disease is essential for anyone affected by cognitive decline. Dementia is a symptom syndrome, while alzheimer's is the most common disease causing it. Recognising this distinction helps families navigate diagnosis, understand what to expect, and access appropriate care and support. As research continues to advance, hope grows for better treatments and eventually a cure for alzheimer's disease and other forms of dementia.
If you're concerned about memory loss or cognitive changes in yourself or someone you care about, don't wait—early evaluation and intervention can make a meaningful difference in quality of life and care planning. At KD Hospital, we have a skilled team of neurologists and neurosurgeons, utilising advanced technology — all under one roof — to provide comprehensive, compassionate, and expert care.
