Dementia vs. Alzheimer's Disease: What is the Difference? Dementia is a general term for a decline in mental ability severe enough to interfere with daily life, while Alzheimer's is a specific disease. Alzheimer's is the most common cause of dementia.
While dementia is a general term, Alzheimer's disease is a specific brain disease. It is marked by symptoms of dementia that gradually get worse over time. Alzheimer's disease first affects the part of the brain associated with learning, so early symptoms often include changes in memory, thinking and reasoning skills.
Alzheimer's disease starts in the brain many years before symptoms start to show. Early symptoms are mild and so don't stop someone doing their normal everyday activities. It's only later that symptoms become severe enough to be called 'dementia'.
Memory loss that disrupts daily life. Poor judgment, leading to bad decisions. Loss of spontaneity and sense of initiative. Losing track of dates or knowing current location.
The average life expectancy figures for the most common types of dementia are as follows: Alzheimer's disease – around eight to 10 years. Life expectancy is less if the person is diagnosed in their 80s or 90s. A few people with Alzheimer's live for longer, sometimes for 15 or even 20 years.
Administration: The examiner reads a list of 5 words at a rate of one per second, giving the following instructions: “This is a memory test. I am going to read a list of words that you will have to remember now and later on. Listen carefully. When I am through, tell me as many words as you can remember.
The Mini-Cog test.
A third test, known as the Mini-Cog, takes 2 to 4 minutes to administer and involves asking patients to recall three words after drawing a picture of a clock. If a patient shows no difficulties recalling the words, it is inferred that he or she does not have dementia.
Many people affected by dementia are concerned that they may inherit or pass on dementia. The majority of dementia is not inherited by children and grandchildren. In rarer types of dementia there may be a strong genetic link, but these are only a tiny proportion of overall cases of dementia.
Memory problems
Difficulties with memory are the most well-known first signs of dementia. For example, a person may not recall recent events or may keep losing items (such as keys and glasses) around the house. Memory loss is often the first and main symptom in early Alzheimer's disease.
Working memory and long-term declarative memory are affected early during the course of the disease.
Overall, know that Alzheimer's disease is a specific disease, while dementia is a general term for a group of similar diseases, of which Alzheimer's is one. In other words, every case of Alzheimer's disease is an example of dementia, but not every type of dementia is Alzheimer's.
The Montreal Cognitive Assessment (MoCA) is a tool that helps healthcare professionals detect mild cognitive impairment and Alzheimer's disease in people. A 2021 study found that it is a better measure of cognitive function than the MMSE. It consists of 30 questions that take 10–12 minutes to accomplish.
Medical Tests for Diagnosing Alzheimer's
Testing for Alzheimer's or other dementias entails diagnostic, cognitive or blood tests, MRI, CT or PET brain imaging, neurological exams or other assessments.
The five-minute cognitive test (FCT) was designed to capture deficits in five domains of cognitive abilities, including episodic memory, language fluency, time orientation, visuospatial function, and executive function.
You have trouble following a conversation. You find it hard to make decisions, finish a task or follow instructions. You start to have trouble finding your way around places you know well. You begin to have poor judgment.
Short-term memory/delayed recall: Five words are read. The test-taker is asked to repeat them. After completing other tasks, the person is asked to repeat each of the five words again. If they can't recall them, they're given a cue of the category that the word belongs to.
The Self-Administered Gerocognitive Exam, known as SAGE, is a brief, pen-and-paper cognitive assessment tool designed to detect the early signs of cognitive, memory, or thinking impairments. The test evaluates your thinking abilities. This can help your doctors understand how well your brain is functioning.
The clock-drawing test is a quick way to screen for early dementia, including Alzheimer's disease. It involves drawing a clock on a piece of paper with numbers, clock hands, and a specific time. The inability to do so is a strong indication of mental decline.
Common early symptoms of dementia
memory loss. difficulty concentrating. finding it hard to carry out familiar daily tasks, such as getting confused over the correct change when shopping. struggling to follow a conversation or find the right word.
Stress, anxiety or depression can cause forgetfulness, confusion, difficulty concentrating and other problems that disrupt daily activities. Alcoholism. Chronic alcoholism can seriously impair mental abilities. Alcohol can also cause memory loss by interacting with medications.
Mini-Mental State Examination (MMSE)
This test is currently the most widely used cognitive assessment tool. It takes 10-15 minutes to administer. It is scored out of 30, with a score below 24 suggesting dementia. It is used to assess global cognitive status.