Did you know that some people can develop amyloidosis as they age — even without an inherited mutation (change) in their genes? Wild-type amyloidosis (also known as senile amyloidosis) typically affects people as they get older. In this condition, a protein called transthyretin (TTR) changes shape, or misfolds, and builds up in the heart and sometimes other organs.

Symptoms of wild-type amyloidosis often resemble those of other heart conditions, which can make it hard to diagnose. That’s why it’s important to see a specialist who is familiar with amyloidosis.

This article explains what wild-type amyloidosis is, how it develops, and what symptoms to watch for. We’ll also cover available treatments and what to expect when living with this condition.

What Causes Wild-Type Amyloidosis?

Normally, cells make proteins that carry out a variety of important tasks. In people with amyloidosis, some of these proteins don’t fold into the right shape. Instead, they misfold and stick together, forming clumps called amyloid deposits or amyloid fibrils. These deposits can build up in different parts of the body and interfere with how organs and tissues work.

There are several types of amyloidosis. Each one is caused by a different misfolded protein and tends to affect specific organs and tissues — for example, the heart, kidneys, nerves, or tendons.

Wild-type amyloidosis is caused by a protein called transthyretin. As some people get older, their TTR proteins can become unstable, misfold, and form amyloid deposits in the heart.

Wild-Type vs. Hereditary Amyloidosis

Wild-type amyloidosis is closely related to another type called hereditary ATTR amyloidosis, also known as familial ATTR amyloidosis.

Hereditary ATTR amyloidosis is caused by a mutation in a gene that’s passed down in families. This mutation causes the liver to make abnormal TTR proteins that tend to build up in the nerves, kidneys, and heart.

Wild-type ATTR amyloidosis, on the other hand, isn’t caused by a gene mutation and doesn’t run in families. The term “wild-type” means the TTR protein is not mutated — it’s considered normal. However, with age, the normal protein may still become unstable and misfold, leading to amyloid deposits, especially in the heart.

Who Develops Wild-Type Amyloidosis?

Wild-type amyloidosis mostly affects men who are at least 60 years old, according to the Amyloid Research Consortium. In fact, health researchers estimate that at least 1 percent of males over the age of 80 have wild-type amyloidosis, according to Amyloidosis Foundation.

However, some researchers think that wild-type amyloidosis may be more common than we realize — but it’s underdiagnosed. This is because many of its symptoms overlap with other heart conditions. Another challenge is that only one-quarter of older people with wild-type amyloidosis experience noticeable symptoms.

Wild-Type Amyloidosis and Dementia

Wild-type amyloidosis has many other names, including:

• Wild-type ATTR amyloidosis
• ATTRwt amyloidosis
• Wild-type transthyretin amyloidosis

You may also come across older names like senile systemic amyloidosis or senile cardiac amyloidosis. These terms are now considered outdated.

Despite what the word “senile” might suggest, wild-type amyloidosis is not a known direct cause of dementia. However, some newer studies suggest there may be a connection between transthyretin proteins and Alzheimer’s disease. More research is needed to better understand the link between these two conditions.

Wild-Type Amyloidosis Symptoms

Wild-type amyloidosis often leads to a heart condition called cardiomyopathy, which makes it harder for the heart to pump blood. This happens when amyloid proteins build up in the heart, causing the muscle to become thick and stiff.

Many symptoms of wild-type amyloidosis resemble those of congestive heart failure. They can include:

• Dizziness or lightheadedness
• Fatigue (extreme tiredness that doesn’t improve with rest)
• Unintentional weight loss
• Shortness of breath, especially during activity
• Swelling in the legs or ankles
• Atrial fibrillation or other arrhythmias (irregular heartbeats)
• A heartbeat that’s abnormally fast or slow

Amyloid deposits can also form in the nerves, compressing the median nerve in the wrist. This can lead to carpal tunnel syndrome — which may be one of the first symptoms people notice. Carpal tunnel syndrome causes numbness, weakness, tingling, or pain in the hand or wrist.

In some cases, wild-type amyloidosis also leads to peripheral neuropathy, a type of nerve damage. Symptoms may include numbness, pain, and extreme sensitivity to touch, often starting in the feet and legs and possibly spreading to the hands.

Another possible sign of wild-type amyloidosis is a tear in the biceps tendon. This tendon connects the upper arm muscle to the shoulder and elbow bones. A tear may cause a visible bulge in the upper arm or lead to pain in the elbow or shoulder.

Symptoms outside the heart may show up as much as 10 years before heart-related symptoms appear.

Diagnosing Wild-Type Amyloidosis

Getting an accurate diagnosis of wild-type amyloidosis is essential. This condition can look a lot like other heart diseases — but the treatments are not the same. In fact, some of the medications that help manage other heart conditions may be harmful to people with wild-type amyloidosis.

Physical Exam

During a physical exam, your doctor will ask about your symptoms and check for signs of cardiac amyloidosis or other conditions. Make sure to tell them about any new or worsening symptoms — even ones that seem minor. The more specific you are, the easier it is for your doctor to understand what’s going on.

Imaging Tests

Doctors often use heart imaging to check how well the heart is working.

• An echocardiogram uses ultrasound to show how well your heart pumps blood. It can also detect signs of damage caused by amyloid deposits.
• Cardiac MRI uses magnets and radio waves to take detailed images of the heart. This test helps your doctor see changes in the heart’s structure and function.

Your doctor might also use a test called a cardiac pyrophosphate (PYP) scan, which is noninvasive in nature compared to traditional biopsies for cardiac diagnosis. It uses a radioactive form of PYP that collects in areas with abnormal ATTR proteins. A special camera and scanner take pictures that light up from the radioactive PYP. The scan helps your doctor determine whether you have wild-type amyloidosis affecting your heart.

Biopsies

In the past, biopsies were a common part of diagnosing amyloidosis. Today, doctors often rely on noninvasive tools like the PYP scan first. However, a biopsy may still be needed in some cases.

Your doctor may take a small sample of fat from your belly (a fat pad biopsy) to check for amyloid deposits. Amyloid can spread throughout the body, and sometimes it shows up in fat tissue. If needed, doctors may also biopsy other organs to see how much they’ve been affected.

Laboratory Tests

Doctors may need to run other tests to determine the type of amyloidosis. Hereditary ATTR amyloidosis and light chain amyloidosis (AL amyloidosis) also affect the heart — so these other conditions need to be ruled out. Your doctor will likely take a small blood sample to look for other abnormal proteins. People with AL amyloidosis have light chain proteins. If you have a positive PYP scan and no light chains, you likely have wild-type amyloidosis.

Hereditary ATTR amyloidosis develops from specific gene changes. Your doctor can perform genetic testing to rule out the hereditary form and diagnose wild-type amyloidosis.

Other laboratory tests — like blood or urine tests — check to make sure your organs are working correctly. Additionally, certain blood tests may be used to track amyloidosis over time. These tests look for biomarkers or molecules that measure how advanced your disease is. They also help determine how much amyloidosis-related heart damage you have.

Treatment Options for Wild-Type Amyloidosis

Wild-type amyloidosis generally affects the heart, so most people with this condition will be treated by a cardiologist (heart specialist). You may also meet with other specialists trained to treat amyloidosis.

Treatments may have different goals. Some therapies help slow down the disease and keep the amyloidosis under control. Others help relieve symptoms and improve quality of life.

Controlling Amyloidosis

In recent years, the U.S. Food and Drug Administration (FDA) has approved a few drugs to treat wild-type amyloidosis.

Some of these medications are TTR stabilizers. They help the transthyretin protein keep its correct shape, which prevents misfolding and reduces the buildup of amyloid in the heart.

FDA-approved TTR stabilizers include:

• Acoramidis (Attruby)
• Tafamidis (Vyndamax)
• Tafamidis meglumine (Vyndaqel)

Another medication, diflunisal, is a nonsteroidal anti-inflammatory drug (NSAID) that stops amyloid formation. Although it’s not officially FDA-approved for amyloidosis, doctors sometimes use it “off-label” based on how it works in the body.

Researchers have developed other drugs that act as gene silencers. They reduce production of transthyretin protein in the liver to help prevent amyloid buildup and organ damage. Vutrisiran (Amvuttra) is a gene silencer approved to treat people with cardiomyopathy caused by wild-type amyloidosis.

Treating the Symptoms of Wild-Type Amyloidosis

People with wild-type amyloidosis may take some of the same medications that are prescribed to people with heart failure. Your doctor may prescribe diuretics (water pills) to get rid of extra fluid in the body. They help treat shortness of breath and swelling. Eating a diet low in sodium (salt) also helps remove extra fluid and may relieve symptoms.

Medications like beta-blockers, calcium channel blockers, and ACE inhibitors are sometimes used to treat heart problems. However, most people with wild-type amyloidosis shouldn’t take these medications, because they can cause additional damage. For example, they can sometimes lower blood pressure excessively or not be effective in the context of a stiff, thickened heart muscle.

Some people with severe wild-type amyloidosis develop lasting heart damage. In this case, doctors may recommend a heart transplant. During this surgery, a person’s heart is replaced with a healthy heart from a donor.

Outlook With Wild-Type Amyloidosis

Thanks to new treatments, people with wild-type amyloidosis are living longer, healthier lives. One study followed people with heart disease from amyloidosis who took tafamidis. The authors found that after almost 5.5 years, 52.4 percent of those with wild-type amyloidosis were still alive.

Other studies show that nearly 80 percent of people diagnosed at age 80 or older live more than 18 months. Certain factors play a role in the outlook with wild-type amyloidosis, including:

• Older age
• Certain proteins or biomarkers related to how well your heart works
• How well a person is able to take care of themselves and perform daily activities

Wild-type amyloidosis is a disease that develops relatively slowly. Although amyloid deposits continue to build up within organs over time, this is a slow process. As a result, people with wild-type amyloidosis often have a better prognosis than those with other types of amyloidosis. While amyloidosis is a serious condition, advancements in treatment are offering hope for a better quality of life and longer survival.

Talk With Others Who Understand

MyAmyloidosisTeam is the social network for people with amyloidosis and their loved ones. On MyAmyloidosisTeam, members come together to ask questions, give advice, and share their stories with others who understand life with amyloidosis.

Are you living with wild-type amyloidosis? Share your experiences in the comments below, or start a conversation by posting on your Activities page.