How Fast Does Dementia Progress?

Although it is often spoken of as a single disease, dementia is an umbrella term for a group of different conditions that affect a person’s cognitive abilities, including memory, thinking, and behavior. The tricky part is that each form of dementia progresses along its timeline, which is affected by a person’s genetics, lifestyle, and treatment plan. 

Together, we’ll unpack the differences between a few types of dementia and discuss how quickly they progress. We’ll also talk about what you can do to protect yourself against cognitive decline and slow the progression of dementia if you’ve already been diagnosed. 

Understanding Dementia

There are numerous types of dementia. Dementia refers to a decline in cognitive faculties affecting various parts of the brain. In virtually all types of dementia, the hippocampus (where memories are stored) is compromised. 

Additionally, the frontal lobes and temporal lobes, which are responsible for executive function, personality, and language, may also be affected. Dementia changes how a person thinks, reacts, behaves, learns, and retains memories. Dementia also makes it harder for a person to focus.

It’s important to understand that dementia is not the same thing as age-related cognitive decline that results in a person feeling like they have brain fog, aren’t as sharp as they used to be, or are becoming forgetful. These aspects of cognitive decline are normal and do not impact a person’s life to the degree that dementia does. 

There are several different types of dementia, each affecting a person differently and progressing along a different timeline.

Types of Dementia

There are over 100 different types of dementia, but five are the most common. These five types of dementia affect millions of people worldwide. Understanding these types of dementia can help you care for a loved one who has been diagnosed and look for signs of progression if you have been diagnosed.

Alzheimer’s Disease

The most common form of dementia is Alzheimer’s Disease. It affects approximately 6.7 million Americans. Alzheimer’s is caused by the abnormal buildup of two proteins in the brain: amyloid plaques and tau tangles. The buildup of these proteins causes brain cells to lose their ability to communicate with one another, which eventually leads to cellular death. 

A person may be genetically predisposed to developing Alzheimer’s, but other risk factors include cardiovascular disease and diabetes. Most Alzheimer’s patients are diagnosed after age 65, but early-onset Alzheimer’s can occur in patients as young as 40. 

Alzheimer’s starts with changes in the hippocampus that cause a person to become overly forgetful. As the disease progresses, a person may lose the ability to speak, have a reduction in judgment, and even lose mobility and control of bodily functions. 

Progression speed: When a person is diagnosed with Alzheimer’s disease, they may live an additional three to 11 years, on average. However, lifestyle changes, treatment options, and a person’s genetics may allow them to live longer than this estimate. 

Vascular Dementia

The second most common type of dementia is vascular dementia. This type of dementia is caused by a reduction in blood flow to the brain, which can happen due to a stroke or a series of mini-strokes. It is more common in adults over 65 with cardiovascular problems than in any other sector of the population. 

Symptoms of vascular dementia differ from symptoms associated with Alzheimer’s in that vascular dementia usually impacts a person’s speech and mobility before it causes memory loss. 

A person with vascular dementia may have trouble with movement and balance and may notice differences or changes in processing speed and decision-making before they notice that they’re becoming a bit more forgetful. 

Progression speed: Unlike Alzheimer’s, vascular dementia progresses through dramatic “steps.” This means a person may notice a major change that occurs quickly, not over time. Once a person is diagnosed, their life expectancy is approximately five years.

Lewy Body Dementia

Another form of dementia that affects proteins in the brain is Lewy Body Dementia. This form of dementia is so-named due to the abnormal collection of proteins called Lewy bodies that form inside healthy brain cells. These protein clusters cause symptoms that are similar to Alzheimer’s disease. 

Lewy Body Dementia is primarily diagnosed in people over the age of 70. However, people as young as 50 can have this disease. 

Lewy Body Dementia has side effects that can be severe. Frequent, vivid hallucinations are common with this disease, as are movement problems that mimic Parkinson’s disease. Lewy Body Dementia also impacts a person’s ability to get REM sleep. 

Researchers are not sure what causes the Lewy bodies to cluster together inside healthy brain cells, but genetics and other brain-related disorders are suspected factors. 

Progression speed: Lewy Body Dementia progresses in a similar way to Alzheimer’s, with symptoms worsening over periods. Once a person is diagnosed, they have a life expectancy that ranges between five and eight years. 

Frontotemporal Lobe Dementia

Frontotemporal lobe dementia is diagnosed in younger populations. Unlike other forms of dementia, patients as young as 45 may develop this disease. With this type of dementia, a person’s personality may be affected first. 

Symptoms may not be as easily noticeable. A person may begin to experience personality changes, like acting differently in social situations, or becoming apathetic or uncaring. Memory problems do not usually occur until much later. 

Genetics plays a role in whether or not a person will develop this type of dementia. In addition, factors like head trauma can play a role. 

Progression speed: A person’s life expectancy once symptoms from this type of dementia appear ranges from two to 10 years. 

Mixed Dementia

Many dementia patients, especially older adults who have already been diagnosed with one form of dementia, develop another type of dementia at the same time. When a person has more than one form of dementia, they are said to have Mixed Dementia. Unfortunately, a person’s risk for mixed dementia increases if they are diagnosed with any other form of dementia. 

Most people with mixed dementia are older than 65, but it is possible to have mixed dementia at a younger age. Mixed dementia may have numerous symptoms and may progress faster than Alzheimer’s disease, because the brain is dealing with multiple sources of damage. 

Progression speed : Mixed dementia progresses faster than Alzheimer's, but it is difficult to quantify life expectancy due to the varying forms of dementia a person with Mixed Dementia may have. 

Although these diseases are serious and can shorten a person’s longevity and healthspan, there are steps you can take to protect your brain health. Even if you are genetically predisposed to cognitive disease, you can take steps to delay the onset of cognitive issues and slow their progression. 

Supporting Cognitive Health

There’s no cure for dementia (yet), but there are ways to support your cognitive health: 

• Keep moving.  Exercise boosts blood flow to the brain and helps maintain brain volume.
  
• Stay socially active. Isolation accelerates cognitive decline. Staying socially engaged helps keep your brain circuits active.
  
• Make sleep a priority. Deep sleep is when your brain actively cleans house. During deep sleep, excess proteins (like the ones associated with dementia) are cleared away.
  
• Eat a balanced diet. Whole foods like fruits, vegetables, and whole grains are the best options for keeping your brain healthy.
  
• Stay mentally engaged.  Puzzles, brain-teasers, and learning new skills can be great ways to keep your brain sharp.
  
• Manage stress. Stress can shrink parts of the brain associated with cognitive decline. If you are chronically stressed, finding methods of managing your stress can be helpful. 

In addition, there’s a supplement you can take once a day to support your cognitive health and longevity. It’s fatty15. 

Fatty15 and Brain Health

Fatty15 is a pure C15:0 supplement. C15:0 is a simple fatty acid that is essential to our bodies (which means we need it to thrive but cannot readily make it on our own), but difficult to come by in our diets. 

Recently, researchers studying bottlenose dolphins discovered that the presence of amyloid plaques and inflammation in the dolphins’ brains mirrors the conditions in the human brain when dementia is diagnosed. 

Interestingly, dolphins with higher levels of C15:0 had fewer occurrences of these factors, suggesting that C15:0 has a neuroprotective effect.

How Does C15:0 Support Cognitive Function?

A recent study funded by the Office of Naval Research examined the potential of fatty15 (C15:0) to directly support brain health. The research aimed to identify compounds with neuroprotective properties.

Published in the International Journal of Molecular Sciences, the study found that C15:0 demonstrated two dose-dependent actions that may promote cognitive wellness:

FAAH Inhibition

C15:0 was shown to inhibit the enzyme fatty acid amide hydrolase (FAAH). To understand why this matters, it helps to start with endocannabinoids. These naturally occurring compounds in the body help regulate immune balance in the brain and support emotional and cognitive well-being.

As we age, FAAH activity tends to increase, which leads to a faster breakdown of these “feel-good” molecules. This process has been linked to declines in mood and cognitive performance over time. By blocking FAAH, C15:0 may help preserve these helpful compounds, potentially supporting brain health, restful sleep, joint comfort, and emotional balance.

MAO-B Inhibition

C15:0 also appears to inhibit monoamine oxidase B (MAO-B), an enzyme responsible for breaking down dopamine, a neurotransmitter crucial for memory, mood, and overall cognitive function. With age, MAO-B levels tend to rise, leading to reduced dopamine availability.

By limiting MAO-B activity, C15:0 may help maintain healthy dopamine levels, contributing to clearer thinking, a calmer mood, and better sleep. Research by Knoll and Ruehl, among others, has also shown that MAO-B inhibitors can extend the lifespan of animals, further highlighting their potential role in healthy aging.

Due to the many anti-aging benefits of MAO-B inhibitors (aka fatty15), these molecules have been proposed as a means to slow biological aging and protect against age-related cognitive decline. Well, that’s pretty exciting.

These findings align with earlier human studies suggesting that individuals with higher C15:0 levels tend to perform better on cognitive assessments, with reported improvements in memory and emotional well-being.

FAQs

What is the life expectancy of a person with dementia?

Life expectancy for individuals with dementia varies significantly based on several factors, most notably the type of dementia and the age at diagnosis. Generally, after symptoms appear, life expectancy ranges between eight and 10 years. 

What is the first symptom most likely to be seen in vascular dementia?

Early signs of vascular dementia can be trouble with movement and slowness of thought. Decision-making may become harder. Vascular dementia tends to deteriorate in broad, step-like changes instead of gradually over time. 

How do you know what stage of dementia someone is in?

The Global Deterioration Scaled(GDS) is used to provide a framework for assessing a person’s cognitive decline. These stages are categorized as pre-dementia, moderate dementia, and late-stage dementia. Each stage has different symptoms that physicians use to assess a person’s current physical and cognitive abilities. 

Knowledge Is Power

Knowing how dementia progresses and how to reduce your risk of developing it can keep your cognitive health in check. If you or a loved one has already been diagnosed, treatments can help. 

Taking precautions like caring for your body, prioritizing sleep, and managing stress are useful tools in helping keep your brain sharp. Adding in fatty15 is one of the easiest and smartest ways you can support your brain health at any age. 

Sources:

Types of dementia | Alzheimer's Disease International (ADI)

About Dementia | Alzheimer's Disease and Dementia | CDC

Alzheimer's stages: How the disease progresses | Mayo Clinic

Vascular dementia | NHS

Aging-Associated Amyloid-β Plaques and Neuroinflammation in Bottlenose Dolphins (Tursiops truncatus) and Novel Cognitive Health-Supporting Roles of Pentadecanoic Acid (C15:0)

Efficacy of dietary odd-chain saturated fatty acid pentadecanoic acid parallels broad associated health benefits in humans: could it be essential? | Scientific Reports

A review of odd-chain fatty acid metabolism and the role of pentadecanoic Acid (c15:0) and heptadecanoic Acid (c17:0) in health and disease | PubMed