What is Dementia?
In this post, I want to talk about Dementia. The word Dementia basically means loss of cognitive function. Cognitive function means impaired ability to remember, think, reason, solve problems, recognize date or time, difficulty with speech, and carry out routine day-to-day tasks.
I often have patients ask me, "do I have dementia or do I have Alzheimer's?" As a doctor who evaluates, diagnoses, and treats patients for Dementia, I describe it as an umbrella term. In fact, most medical professionals think of Dementia as an Umbrella term. There are different types of Dementia, and Alzheimer's disease is just one type.
Now that we know what Dementia means let us review some of the most common types of Dementia.
To keep this post concise, I will briefly describe the most common types of Dementia. At this time, there is no cure for Dementia. It is a progressive terminal disease. Patients with very severe Dementia can qualify for hospice services based on their dementia stage. Keep in mind that every person is different. They may not present the same way even if diagnosed with the same type of Dementia. Sometimes people can present with a mixed type of Dementia which is a combination of Dementias.
Alzheimer's Dementia is the most common type of Dementia impacting over 5 million people 65 years and older. The onset of Alzheimer's disease is gradual over 8 to 10 years on average. Symptoms include memory loss, difficulty learning new information, language, and visuospatial problems. Disease progression leads to more memory loss, difficulty managing life, finances, repeating questions, taking longer to complete tasks, and sometimes developing personality problems. The disease progresses until there is no function left to preserve. In the latest stages, people may lose the ability to speak, feed themselves, or walk.
Vascular Dementia is a type of Dementia causing memory loss and loss of cognitive function due to vascular injury to the brain. The severity of the disease depends on the size and location of the brain injury. Sometimes it is hard to distinguish this type of Dementia from Alzheimer's type. This type of Dementia can be seen in patients who have had strokes, uncontrolled blood pressures, diabetes with uncontrolled blood sugars, and high cholesterol. Other risk factors include smoking, an unhealthy diet, obesity, and little to no physical exercise. This type of Dementia usually takes a step-wise approach. For example, a person may have a stroke followed by loss of function. They may remain stable for a while, but they experience more cognitive decline. For younger adults, managing chronic vascular diseases may sometimes prevent Vascular Dementia.
Lewy Body Dementia
Lewy body Dementia, also referred to as LBD, is another common type of Dementia. Usually begins after the age of 50, but in rare instances earlier. It is caused by abnormal protein deposits in the brain called Lewy Bodies. Symptoms can vary but generally include memory loss, other cognitive loss, behavioral issues such as agitation, hyperactivity or depressed mood, and sleep-related symptoms. More commonly, patients with LBD experience hallucinations. This disease can sometimes be confused with Parkinson's disease because people with LBD also experience tremors, posture changes, and a shuffling walk. This disease can also be mistaken for Alzheimer's disease depending on symptoms presentation. Ultimately, it progresses until there is no function left.
Frontotemporal Dementia is a disease often seen in younger patients, generally 60 years and younger. Patients develop cognitive function loss such as planning out tasks, memory issues. Additionally, they experience behavioral problems. Due to the areas affected by this disease some people may experience difficulty understanding words, recognizing objects, emotional instability, and impulsive behaviors. The disease progresses differently for everyone, some more rapid than others. Therefore on average people with frontotemporal Dementia can live 2-10 years.
Other Dementias have been identified that cause cognitive decline not related to the above more common conditions. I will review two of the more rare forms of neurodegenerative dementias.
Creutzfeldt-Jakob Disease- This type of Dementia is believed to be related to infection. The infection is believed to be caused by prions, which are misshaped particles (we refer to this as proteins). Prions are not viruses or bacteria. Patients rapidly decline, usually live 1-2 years after diagnosis.
Chronic traumatic encephalopathy (CTE)- This type of Dementia is caused by repeated traumatic brain injury. Generally occurs in individuals who have experienced multiple concussions, such as football players. Symptoms can include memory loss, mood and behavioral changes, balance issues, tremors similar to Parkinson's disease. Generally, those with CTE start to present with symptoms 20 or more years after repeat injury. This disease is terminal; progression and decline vary depending on trauma history.
Other diseases can cause dementia including Huntington's disease, HIV, Wilson's disease, multiple sclerosis, meningitis, encephalitis and others.
I hope that you found this blog post informative. My goal was to briefly identify Dementia and clarify some of the differences between the most common types of Dementia. Please consider reading the our blog post on normal and abnormal cognitive changes that occur with aging. I did not cover rare types of Dementia. As you can see, it is Crucial to consider an evaluation by a dementia specialist if you or a loved one are experiencing cognitive decline symptoms. The best place to start is by contacting your primary care provider.