It is truly helpful to understand there are multiple different types of dementia, all of which may present with different symptoms, and may have vastly different prognoses and treatment options. In general, there are 5 major groups; Primary, Secondary, Progressive, Cortical, and Subcortical Dementia. Classification in one of these groups is not exclusive of another group either, i.e. some dementia can be primary, progressive, and subcortical, because this classification system tends to group disorders based on shared features, such as cause, and location of the brain affected.

Better definitions of these dementia groups are the following:

  • Cortical dementia: dementia where the brain damage primarily affects the brain’s cortex, or outer layer. Cortical dementias tend to cause problems with memory, language, thinking, and social behavior.
  • Subcortical dementia: dementia that affects parts of the brain below the cortex. Subcortical dementia tends to cause changes in emotions and movement in addition to problems with memory.
  • Progressive dementia: dementia that gets worse over time, gradually interfering with more and more cognitive abilities.
  • Primary dementia: dementia such as Alzheimer’s disease that does not result from any other disease.
  • Secondary dementia: dementia that occurs as a result of a physical disease or injury.

As previously mentioned, some of the more commonly known and diagnosed dementing disorders, such as Alzheimer’s disease, and Vascular dementia, fit into multiple groups. Below we will try to expand on some of the more commonly diagnosed dementing illnesses.

Alzheimer’s disease (AD) is the most common cause of dementia in individuals 65 and older, and there are nearly 4 million adults currently living with the disease in the United States alone, with between 300,000 and 400,000 new diagnoses each year. The cost of treatment and care for these individuals in the United States is estimated to reach $150 billion this year, and double to nearly $300 billion by 2040. To date, there is no cure for the disease although much research into cause and treatments is underway.

In general, symptoms of AD occur after the age of 60; however there is an early-onset form of AD which can appear as early as age 30. Mild cognitive deficits tend to gradually progress over the course of 7-10 years, with some patients progressing slower, or more rapidly, affecting nearly all brain functions (memory, movement, language, behavior, emotions, and autonomic systems) throughout the progression of the disease.

The root cause of the disease remains unclear, although there are some genetic correlations and environmental and behavior risk factors associated with the disease. The disease is characterized by two main abnormalities in the brain, amyloid plaques, and neurofibrillary tangles, which result in the death of neurons and other cells in the brain. More information on AD causes, pathophysiology, and ongoing research will be covered in an upcoming blog article.

Although, much is still unclear with AD, current research shows some measures can help slow the progression of the disease, such as physical and cognitive exercise, and social stimulation. Current research is focusing on targeting the abnormalities in the brain to help alleviate the symptoms as well as slow the progression of the disease. Significant advances in treatment and possibly prevention are on the horizon.

Vascular dementia is the second most common form of dementia after AD and is the result of death of neurons (brain damage) following problems in blood flow to areas of the brain, most often a stroke (cerebrovascular attack).

Symptoms often begin suddenly, such as following a stroke, and are often stable for years, sometimes even resolving themselves over time. Symptoms vary widely depending on the area and extent of the brain damage, but are more often singular cognitive deficits, such as memory, language, vision, depression, or incontinence issues. There are multiple different subsets of vascular dementia which will also be addressed in a future blog article.

Lewy-body dementia (LBD) is the most common form of progressive dementia, and is a result of a storage disorder in the cortex of the brain. LBD is diagnosed by the detection of Lewy bodies in the brain’s cortex. The symptoms of LBD are often similar to those of AD as well as sharing many symptoms with Parkinson’s disease such as visual hallucinations and shuffled gait.

There is currently no cure, but symptoms are often treated similar to Parkinson’s disease with cholinesterase inhibitors and neuroleptic drugs, both of which require close monitoring.

Frontotemporal dementia (FTD) is a set of dementias characterized by death of brain cells primarily in the frontal or temporal lobes of the brain. These lobes of the brain generally control judgment and social interactions, therefore many patients have problems in social situations. One of the more common types of FTD in called Pick’s disease where neurons die as a result of lack of clearing of cholesterol, but is independent of an individual’s diet. Patients with Pick’s disease may show similar symptoms to LBD and Parkinson’s disease as both are other storage disorders. Primary progressive aphasia is another form of FTD where younger individuals show difficulties understanding and expressing words and eventually show other signs of dementia. There are also some genetically associated FTD’s that present with psychiatric symptoms such as hallucinations and delusions, but are quite rare.

Huntington’s disease is a genetically inherited disorder which results in the degeneration of the neurons in the spine and brain, usually beginning in fourth decade of life. Cognitive symptoms generally tend to occur in the first five years of disease onset.

Creutzfeldt-Jakob disease is a member of a group of disease known as encephalopathies, where in the case of CJD an abnormal protein called a prion causes the death of neurons in the brain results in cognitive deficits and is a progressive disorder. Other progressive dementias include fatal familial insomnia, Corticobasal degeneration, dementia pugillistica, and Gerstmann-Straussler-Scheinker disease among others.

Secondary dementias are typically the result of injuries or neuronal death from other conditions. More often than not, the relationship between the underlying condition and the secondary dementia is unclear, think the chicken and egg situation. Some disorders which often lead to secondary dementias include but are not limited to ALS, Parkinson’s disease, Pick’s disease, Wilson’s disease, motor neuron disease, and normal pressure hydrocephalus.

Lastly there must be made the distinction between delirium and dementia. Quite often a patient may present with a cognitive deficit of psychiatric symptom, as a result of an underlying condition, known as delirium. Many of these presentations are transient, and can sometimes be a result of a condition, or an adverse drug interaction, and be self-resolving.

In summary, the term dementia is a well-known, yet mis-understood umbrella term which includes a plethora of conditions, all of which require the affected individual to need assistance with daily activities to some degree. It is imperative to better understand the underlying causes of a situation, and work with trained professionals to assist in caring for someone with dementia. More often than not, dementias are progressive and incurable, but daily physical, mental, and social stimulation combined with a healthy diet in a safe and secure environment can ease the process and slow the progression of some diseases.

For more than 24 years, Centennial Adultcare Center has cared for persons with all of the above conditions, among many others. Please contact us today and see how we can help in caring for your beloved.