Frontotemporal Dementia (FTD) and ALS

It is important to understand that frontotemporal dementia is different from the type of dementia associated with diseases like Alzheimer’s. FTD does not affect a person’s memory in this way. Instead, it can result in changes in personality and behavior due to a loss of nerve cells in the frontal and temporal lobes of the brain.

Subtle behavioral changes can be hard to detect. Loved ones may be the only ones who notice things like increased irritability, poor judgment, decreased motivation, and out-of-character behavior. People with FTD symptoms may still be able to function normally in some parts of their lives.

FTD is progressive, which means that after symptoms begin, they will typically continue to become more pronounced. The specific symptoms and rate at which they progress differ from person to person.

Symptoms of frontotemporal dementia include:

• Behavior that is inappropriate, inconsiderate, or out of character
• Anger or irritability
• Apathy
• Impulsivity
• Self-centeredness
• Mental rigidity
• Poor judgment
• Impaired social skills
• Distractibility
• Repetitive behaviors
• Changes in language ability

In some cases, there is a genetic association with ALS and FTD. There are multiple genetic variants (sometimes called mutations) in certain genes that can cause ALS and FTD in the same person or in the same family. The most common ALS-associated gene, C9orf72 (often referred to as C9), has a strong correlation with FTD. Family members with a variant in the C9 gene may develop ALS, FTD, or both.

An estimated 40% or more of all FTD cases are considered familial, meaning that a parent passes down a genetic variant to a child. Children of parents with a genetic variant typically have a 50% chance of inheriting that same variant.

The only way to find out if you have a genetic variant associated with ALS or FTD is to have genetic testing. If you consider testing, meeting with a genetic counselor first is strongly recommended. A genetic counselor can provide support and guidance, assess your risk, provide information about testing, and more.

Who should get tested for genetic ALS?

Current guidelines state that anyone diagnosed with ALS should be offered genetic testing for at least the most common genetic variants. Deciding whether or not to get tested is a highly individual decision.

Unfortunately, frontotemporal dementia can be missed and misdiagnosed. There is no one test that can diagnose FTD. A doctor must look at a person’s family history, symptoms, and the results of a comprehensive neuropsychological evaluation in order to determine whether a person has FTD.

If you suspect that your loved one may be showing signs of FTD, you can schedule an appointment with a neurologist who is knowledgeable in both ALS and FTD. A behavioral neurologist or neuropsychologist may also be able to conduct the evaluation. You may want to call or email ahead of time to share your concerns because your loved one may be unaware that they are acting differently.

It is common for a person with FTD to be unaware of their disease and how it affects others. This lack of awareness is not due to denial. It is due to physical changes in the brain. Trying to convince your loved one or explain that they have FTD can be difficult and may not be understood.

Remember that these challenging new behaviors are likely due to changes to the brain—not because your loved one is trying to be difficult or because you are doing something wrong.

​Unfortunately, there is no cure or treatment for FTD. A confirmed diagnosis, though, can help you plan ahead, develop interventions, and seek support.

If your loved one is not thinking as clearly as before but is open to your assistance, you can help by scheduling ALS clinic visits, taking notes, communicating with the medical team, and trying to help your loved one comply with medical recommendations.

You may also want to take a greater role in helping your loved one make important medical and end-of-life decisions, ideally sooner rather than later. People with FTD are often less likely to follow guidance on medical recommendations like noninvasive ventilation (NIV) and feeding tubes, which means they can have a shorter life expectancy.

When possible, it may be helpful to find ways to avoid situations where challenging behaviors can be triggered. For example, if impulsive financial decision-making is a concern, you could set up a separate bank account with a lower balance.

Caring for people living with FTD can be very challenging. Caregivers can strategize with their ALS clinic team or other medical professionals, seek respite care, practice self-care, join an FTD support group, and explore the following resources for additional information and guidance.