Dementia describes a large group of neurological conditions that all cause changes to the brain's functioning. All types of dementia get worse over time, but they also differ in several ways, including what causes them, how they affect the brain and what symptoms you notice. The average age of diagnosis is also different for each type. Here are the different types of dementia and what makes them unique.
Alzheimer's disease accounts for up to 70% of global dementia cases, making it the most common type. While the causes aren't clear, common suspected causes include aging, genetics, environmental factors and lifestyle choices. Regardless of the cause, Alzheimer's disease has two key identifying effects on the brain: amyloid plaques and tau tangles, which are clumps in the brain that interfere with its functioning.
Forgetfulness is often an early sign. You might repeat questions, get lost in familiar places or forget appointments. Over time, those symptoms progress and may affect your judgment, reaction time, personality and communication abilities. Other symptoms include:
Alzheimer's is typically diagnosed in your mid-60s or older, but early-onset Alzheimer's may become evident as early as your mid-30s. Getting a diagnosis of early-onset Alzheimer's can be difficult because dementia isn't common in younger adults. Medical professionals might look for other explanations of the symptoms, such as stress, anxiety or vitamin deficiencies.
This type of dementia develops after disruption to blood flow in the brain, such as strokes and blood clots. An MRI of someone with vascular dementia often shows signs of strokes, changes to the white matter and damage to small blood vessels in the brain.
While this type of dementia can affect your memory, it often interferes with thinking skills in the early stages. You might notice gradual changes or a sudden onset of symptoms. The symptoms get worse over time, but some people with vascular dementia experience some short, temporary improvements. Symptoms may include:
The severity and the specific abilities it affects depend largely on where in the brain the lack of blood flow occurs. The age of diagnosis is typically over 65.
A less common type of dementia, frontotemporal dementia happens when there's damage in the frontal and temporal lobes of the brain. Over time, nerve cells in those areas die and the brain tissue shrinks. The areas that FTD affects control your behavior and language, so the symptoms often affect those functions. Symptoms may include:
FTD can cause memory issues, but they usually happen at later stages. The diagnosis for this type of dementia often happens between 45 and 64.
In this form of dementia, protein deposits called Lewy bodies form in the brain and interrupt communications between brain cells. Lewy bodies can be present in other types of dementia as well. The symptoms are often similar to both Alzheimer's disease and Parkinson's disease. It affects your thinking and reasoning, and some people experience physical symptoms. Specific symptoms may include:
The symptoms often start out mild and don't affect your normal activities. Over time, the symptoms increase in severity, but the specific rate of decline varies from one person to the next. A diagnosis usually comes at age 50 or older.
Creutzfeldt-Jakob disease is very rare and often causes sudden dementia symptoms that progress quickly. It happens when prion proteins in the brain fold into abnormal shapes. It affects both thinking and muscle movements. Common symptoms include:
This disease is most common in people 60 and older. Because of the rapid progression of the brain damage, people with this type of dementia often pass away within a year.
Some people develop more than one type of dementia at the same time. Common combinations include Alzheimer's disease with vascular dementia and Alzheimer's disease with Lewy body dementia. Mixed dementia is more common in older adults, especially people over 75.
Symptoms of mixed dementia can vary significantly, depending on the types of dementia involved and what parts of the brain the diseases affect. The diagnosis usually focuses on the most prominent type of dementia the doctor notices. It's frequently difficult to diagnose mixed dementia. It's often after the person passes away and an autopsy is performed that mixed dementia becomes evident.
Regardless of the type of dementia you or a loved one develops, the memory care and assisted living communities under the Bethesda Senior Living Communities umbrella offer compassionate care in a safe, secure environment.
