Neurodegenerative Diseases

What are neurodegenerative diseases?

Neurodegenerative diseases are conditions that gradually damage and destroy parts of your nervous system, especially areas of your brain. These conditions usually develop slowly, and the effects and symptoms tend to appear later in life.

This term doesn’t just refer to a single type of condition. Instead, it’s an umbrella term that applies to several types of conditions.

Types of this condition

Some of the main types of degenerative brain diseases include (but aren’t limited to):

• Dementia-type diseases: These cause progressive damage to various areas of your brain, causing neurons in several areas of your brain, to die. That can then cause a wide range of symptoms depending on brain areas affected. These include many conditions, such as Alzheimer’s disease, frontotemporal dementia, chronic traumatic encephalopathy (CTE), Lewy body dementia and limbic predominant age-related TDP-43 encephalopathy (LATE).
• Demyelinating diseases: These involve myelin damage or loss, which affects sending and relaying of nerve signals. Examples include multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD).
• Parkinsonism-type diseases: These happen because of damage to specific neurons in your brain that help manage coordination and precise control of muscle movements. This includes Parkinson’s disease and other forms of parkinsonism (the general term for conditions that look similar to Parkinson’s).
• Motor neuron diseases: These happen when neurons that control movement die off. Examples include amyotrophic lateral sclerosis (ALS, often known as “Lou Gehrig's disease”) and progressive supranuclear palsy (PSP).
• Prion diseases: These are a type of protein misfolding disease that cause serious brain damage in a relatively short time (most people don’t survive more than a year). Creutzfeldt-Jakob disease is the most common, and most cases happen for unknown reasons. It can also be genetic (survival time for these cases is between one and 10 years).

It’s important to remember that there are many areas of overlap between the various degenerative brain diseases. Many of them share symptoms and have causes that work similarly.

How common are degenerative brain diseases?

Degenerative brain diseases are uncommon, but happen often enough to be common knowledge. Researchers estimate they affect more than 50 million people worldwide.

Most of these conditions are strongly connected to age and are much more likely to happen in people over 65 (but some conditions like Huntington’s disease and ALS often appear earlier). The World Health Organization (WHO) projects that the number of people over 65 will at least double in the next 30 years. That means the number of people with neurodegenerative conditions will also climb at a similar rate.

What are the symptoms of neurodegenerative diseases?

The symptoms of neurodegenerative diseases vary widely. Some may have obvious connections to a degenerative brain disease. Other symptoms might seem completely unconnected without specific medical testing.

In general, the different types of conditions cause the following symptoms:

• Dementia-type diseases: These cause confusion, memory loss, trouble thinking or concentrating, and behavior changes.
• Demyelinating diseases: Common symptoms include tingling or numbness, pain, muscle spasms, weakness and paralysis, coordination issues and fatigue.
• Parkinsonism-type diseases: These often involve slowed movements, shaking and tremors, balance problems, shuffling steps and hunched posture.
• Motor neuron diseases: These affect parts of your brain and nervous system responsible for muscle control. As the neurons in those areas die, you lose muscle control. That causes weakness and eventually paralysis.

Why can the symptoms vary so much?

The symptoms of neurodegenerative diseases can vary widely, even among people with the same condition. There are a few reasons for this:

• Each person’s brain is unique. No two brains form or work in exactly the same way. That means the same condition can still affect two people differently.
• Neurodegenerative diseases happen for many different reasons. The possible causes can vary widely for these conditions, even among conditions of the same type.
• The symptoms depend on what’s affected.The parts of your brain or nervous system affected determine the symptoms of these conditions.

What causes neurodegenerative diseases?

Some neurodegenerative diseases have a single cause that healthcare providers can identify. But in many cases, there isn’t a single cause. Instead, research shows multiple factors probably contribute to neurodegenerative diseases. And there are times when providers might not be able to find a cause — which can be frustrating for someone with one of these conditions or their loved ones.

So far, experts have identified dozens of possible causes or risk factors. These tend to fall into a few specific categories, including:

• Age: This is generally the most important factor in developing neurodegenerative diseases. These conditions have strong ties to age. The older you are, the greater your chances of developing one. Some degenerative brain diseases can start earlier in life, but this is less common.
• Genetics: Many neurodegenerative diseases have strong ties to family history. That’s often because of specific mutations you can inherit that increase your risk. Spontaneous mutations can also happen, and sometimes a combination of genes plays a role.
• Environment: Your environment can be a major factor in developing these conditions. Exposure to pollution, chemicals and toxins, certain types of infections and even where you live may all play a role (for example, lower vitamin D levels, which are more common the farther you live from the Earth’s equator, have links to dementia-type diseases).
• Medical history: Your medical history and past health events can all play a role in developing neurodegenerative diseases. Some neurodegenerative conditions can either happen because of specific medical events or can get worse because of them. Some examples include cancer, certain types of infections, if you've had head injuries and more.
• Habits, routine and choices: Examples include what you eat, how active you are, whether or not you use tobacco products, how much alcohol you consume and many more.

What are the complications of neurodegenerative diseases?

Complications are common with neurodegenerative diseases because these diseases damage parts of your brain and nervous system. As the damage worsens, you lose the abilities that the damaged areas once controlled. Some examples of this include:

• Movement disorders affect your strength, flexibility, agility and reflexes. When those decrease, your risk of falls and fractures increases.
• Motor neuron disorders cause gradual paralysis. When this affects muscles that control breathing, it increases the risk of pneumonia and other respiratory conditions.
• Dementia-type diseases affect memory, judgment and thinking. As these worsen, people typically can’t live independently anymore because of risks to their health and safety.

How is it diagnosed?

Diagnosing a neurodegenerative disease varies depending on the condition you have. Healthcare providers can start with a simple neurological exam and by asking you or your loved ones questions about your symptoms and medical history.

Other conditions are diagnosable with specific tests. Some of these include:

• Laboratory testing: Blood tests and genetic testing are sometimes all it takes to diagnose certain neurodegenerative conditions.
• Imaging scans: Computed tomography (CT) scans, magnetic resonance imaging (MRI scans) and other imaging tests are often very important in diagnosing these conditions. They allow healthcare providers to “see” your brain and determine if there’s damage or changes that indicate you have a neurodegenerative condition, or to rule out other causes.
• Histopathology (microscopic tissue analysis) after death: Some neurodegenerative conditions, such as Pick’s disease or chronic traumatic encephalopathy, aren’t diagnosable while you’re alive. Healthcare providers can suspect this condition while you’re alive, but the only way to confirm the diagnosis for certain is to look at samples of your brain under a microscope after an autopsy.

Other tests are also possible depending on the condition you have or the symptoms you show. These can vary widely because they depend on what area of your brain they affect. Your healthcare provider is the best person to tell you what tests they recommend in your situation and why.

How are neurodegenerative diseases treated, and is there a cure?

Unfortunately, all neurodegenerative diseases are incurable. These diseases destroy brain cells, which is impossible to reverse.

Some neurodegenerative diseases are treatable, depending on why they happen. Some of these conditions are treatable directly, so you may be able to manage, limit or slow their effects. Other conditions aren’t treatable directly, but it might be possible to treat the symptoms and improve your quality of life.

Because the treatments can vary so widely, your healthcare provider is the best person to tell you what treatments are possible and which they recommend. The information they provide will be the most relevant and accurate because it also considers the details of your situation, your medical history and more. They can also tell you about the side effects and complications you might experience, what to watch for and any other considerations.

Can this be prevented?

Neurodegenerative diseases happen unpredictably. Most of them happen for reasons that aren’t fully understood. Because of both those facts, they aren’t preventable.

How can I lower my risk?

While neurodegenerative diseases aren’t preventable, there are things you can do to lower your risk of developing one. Because these diseases are often due to a combination of factors, reducing the number of factors may help lower your risk.

Steps you can take to reduce your risk include:

• Eat a balanced diet. Your diet affects your brain health. A poor diet can make your brain more vulnerable to developing a neurodegenerative disorder. It can also make other conditions that could contribute (such as stroke) more likely to happen.
• Stay physically active and maintain a healthy weight. Your weight and activity level also affect your brain. Weight-related conditions and concerns, especially circulatory problems like high blood pressure and metabolic conditions like Type 2 diabetes, can also contribute.
• Wear safety equipment as needed.Head injuries, especially concussions and traumatic brain injuries, can strongly increase your risk of a neurodegenerative disorder. That makes safety equipment invaluable to preventing injury and protecting your brain health in the long run.
• See your primary care provider annually. This can help avoid or delay chronic medical conditions that might later contribute to neurodegenerative diseases. These visits may also help detect neurodegenerative diseases earlier. That’s helpful because many of these conditions are much more treatable in their earlier stages.

What can I expect if I have a neurodegenerative disease?

Because there are so many different neurodegenerative diseases, what you can expect will vary depending on many factors. Some conditions progress at different rates and may take years or even decades to become severe. Others can worsen faster. As a result, your healthcare provider is the best person to tell you what you can expect.

The longer you have a neurodegenerative disease, the more likely complications become. Unfortunately, these conditions can lead to a decrease in quality of life, and eventually cause death (or contribute to something else that causes it).

How long do neurodegenerative diseases last?

Once they develop, neurodegenerative diseases are permanent, lifelong conditions.

What’s the outlook for neurodegenerative diseases?

In general, neurodegenerative diseases will continue to worsen and cause some degree of disability. People with these conditions may be unable to move around without using assistive devices. Others may have trouble thinking or remembering, which eventually means they can’t live independently. It’s common for people with these conditions to need some level of medical care 24/7, such as in a long-term care facility (informally known as a nursing home) or a similar setting.

How do I take care of myself if I have a neurodegenerative disease?

If you have a neurodegenerative disease, taking care of yourself may be possible early on, but eventually, you’ll need help taking care of yourself. Being able to take care of yourself and how long you can do so depend on many factors, especially the condition you have and if you have any other health issues.

Making choices for when you can’t choose for yourself

If you learn you have a neurodegenerative disease of any kind, it’s important to have conversations with people you trust about what you want if you can’t make choices for yourself. These conversations, while difficult, can ensure they know and follow your wishes. This is a good idea no matter what neurodegenerative condition you have (and a good idea for everyone in general).

The people you should talk about this with include:

• Your primary healthcare provider and/or any specialists who help manage your condition.
• Your immediate family.
• Your attorney (if you have one already).
• Other extended family, friends or loved ones you trust to make life-or-death decisions for you.

The topics you should talk about with them include:

• Who you want to speak or make decisions for you, if necessary.
• Financial concerns related to paying for your care.
• Your wishes regarding end-of-life care, a will (living or otherwise), power of attorney, etc.
• What you want for yourself regarding lifesaving or life-prolonging care, etc.

These conversations might feel unpleasant or difficult, but having them sooner rather than later can ensure your loved ones know what you want if you can’t tell them or choose for yourself.

In addition to those conversations, you should also put your wishes and decisions in writing. Consider preparing documents related to legal issues and what happens if you can’t take care of yourself or make decisions for your own care or well-being. You can consult an attorney for help preparing these documents, but many of them you can prepare on your own (you may need a notary or other official to endorse them, depending on the laws in your area).

How do I care for a loved one with a neurodegenerative disease?

If you have a loved one with a neurodegenerative disease, what you can do depends on the condition they have, how advanced it is, other health concerns and more. Your loved one and/or their healthcare provider are the best people to tell you what they might need.

It can be hard for many people with these conditions to talk about what they’re facing. Many people with these conditions fear what’s happening or what might happen in the future. That can make it difficult for them to ask for help. Many feel embarrassed about asking for help or the thought that they might need to rely on others.

If you have a loved one with a neurodegenerative disease, here are some things you can do or keep in mind:

• Don’t treat them like an invalid or burden. Degenerative brain conditions make it hard to do things you used to do easily. Eventually, these conditions can make it hard to do even simple things like bathe, get dressed or go to the bathroom. Treat them with as much dignity and respect as you would anyone. Remember that they’re a person you care about, not the condition they have.
• Ask what they need. Sometimes, people facing a difficult situation just want to vent. If a loved one opens up to you, it may be helpful to ask if they want a listening ear or if they want feedback, suggestions or assistance.
• Offer to help. Your loved one may have trouble asking for help. They might not want to ask for help, or might not feel like they need it. Sometimes, helping them with little things can make it easier for them to rely on you for bigger needs. Going with them to medical appointments, assisting with errands or helping with household chores are all ways you can pitch in.
• Take care of yourself. Caregivers can experience burnout, too. It’s much harder to care for others when you aren’t taking care of yourself. It’s also important to acknowledge when your loved one needs a higher level of care than you can provide. Trying to care for them when you don’t have the training or resources can do more harm than good.

When should I see my healthcare provider, or when should I seek care?

You should see a healthcare provider anytime you have brain-related symptoms or issues that affect your routine and activities. Early detection of neurodegenerative diseases can make a big difference in delaying how fast the disease worsens.

If you know you have a neurodegenerative disease, you should also seek care when:

• Your provider has you scheduled for an appointment. Making these appointments helps your provider monitor your condition and recommend adjustments to treatment or lifestyle that might help.
• You notice changes in your symptoms. These kinds of changes can be important information for your provider to consider as they work to monitor and care for you.
• You notice side effects or changes in treatment effectiveness. Treatments like medication may become less effective with time. Tell your provider if you notice differences in treatment effectiveness. That can also help them adjust your treatment to be more effective and monitor your condition.

Your healthcare provider can also tell you about other things to watch for that mean you need to see them soon or that you need medical care right away.

A note from Cleveland Clinic

Finding out you have a neurodegenerative disease can make you feel shocked, scared or angry. It can also be troubling to face the idea that you might not be able to take care of yourself and live independently because you have one of these conditions. You may also feel that way if you have a loved one with one of these conditions.

While neurodegenerative diseases are permanent and incurable, experts and researchers are continuing to uncover new ways to diagnose and treat these conditions. That means healthcare providers can do even more to treat these conditions, give you a chance to live longer and keep your quality of life as high as possible. That way, you can limit how much these conditions affect your life and focus on what matters most to you.