I Don't Want to Do This to My Children

Worries of a Caregiver About Alzheimer's Disease

I’m guessing that I’m not alone in having a fear that, as a caregiver, my children will someday have to deal with my dementia.

The problem has many underlying worries:

• Will someone have room to take me in?

• Will the expenses of my care be excessive?

• How will I be as someone with dementia? Kind and easy, or grumpy and mean?

• Will I forget them?

So, today, I’m setting out to learn about whether dementia has a genetic component to it. I’ve touched on it in other articles briefly, but I don’t have a definitive answer.

Yet.

The best way to go about it is by looking at the different types of dementia. I’m ready if you are…

Edit: After writing the part about Alzheimer’s and discovering how much there is on the subject, I’ve decided to break this down into a few articles. Otherwise, it’s likely to take you about 30 minutes to read it 📖 I’ll write these over the next few weeks.

Photo by National Cancer Institute on Unsplash

Alzheimer’s Disease

Familial Alzheimer’s Disease

There is a rare form of Alzheimer’s Disease called Familial Alzheimer’s Disease (FAD). By it’s name, you might guess that it’s genetically passed down, and it is. Lucky for me, age is in my favor this time.

FAD usually shows itself by age sixty-five, so I guess I’m not quite out of the woods yet as I’ll turn sixty-two in about ten days.

However, one of the characteristics of FAD is that it’s a form of early-onset Alzheimers, usually appearing in some cases as early as the thirties or forties.

FAD only represents about five percent of all Alzheimer’s cases, which means that approximately 350,000 people worldwide may have it.

To inherit FAD, you only need to have one parent who had it previously, and if you do, you have a fifty-percent chance of developing it yourself.

I don’t want to get into the genetics here, but there are three genes associated with FAD, sometimes called EOFAD (Early Onset FAD). You only need to have a mutation of one of those genes to give you that fifty-percent chance.

Since my grandmother had Alzheimer’s Disease, but not FAD, I feel pretty confident that I won’t develop FAD in the future.

Alzheimer’s Disease

So far, science can tell us that multiple genes, combined with how you live your life can influence whether you get Alzheimer’s disease. It’s possible that someone in your family has had Alzheimer’s disease without you ever developing it yourself.

There are people who have Alzheimer’s disease who have no family history of it, at least for as long as we’ve been tracking such things.

Then there are people who have parents or siblings with Alzheimer’s who are indeed at higher risk of developing it themselves.

Since my mother’s mother had Alzheimer’s and her sister has unspecified dementia, the likelihood of her getting it seems to be pretty high. Should Mom get Alzheimer’s, that would increase my risk as well.

Science has, as of the writing of the report I read, identified no fewer than eighty genetic areas associated with Alzheimer’s. This number increased from the ten that were identified in 2013.

The Apolipoprotein E (APOE) Gene

This gene is responsible for carting cholesterol and some types of fat around your bloodstream. When problems develop in this transportation system, your risk for Alzheimer’s goes up.

Now, here’s the tricky part. Some forms of APOE, called alleles, can actually reduce your risk. Go figure!

APOE ε2 may provide protection against Alzheimer’s.

Gimme some of that!

Roughly five to ten percent of people carry this gene. Should someone with this allele develop Alzheimer’s, it will be later in life.

APOE ε3 is the most common allele and seems to have no bearing on Alzheimer’s. It doesn’t increase or decrease your risk. It just is.

I’ll take two of these please.

APOE ε4 is the allele you don’t want. This one increases your risk and also seems to be related to earlier onset Alzheimer’s in certain populations.

About fifteen to twenty-five percent of the population carries one copy of this allele with two to five percent having two copies.

Now, here’s where it gets fun. I always loved this part of science when I was a kid. Everyone has two of these APOE alleles, so there are six possible combinations, each increasing or decreasing your risk (I’ll just be using the ε2 number, so 2, 3, or 4):

• 2/2

• 2/3

• 2/4

• 3/3

• 3/4

• 4/4

It doesn’t take a genius to determine that if you have 3/3, you have a lower risk of developing Alzheimer’s while having 4/4 would increase your risk.

One Saving Grace

Some people have APOE ε4 and do not ever develop Alzheimer’s, so having this allele isn’t an Alzheimer’s sentence. It just increases your risk. This is important to understand!

Another Possible Component

Studies conducted by the NIH (National Institute of Health) are looking into whether other genetic factors, such as what region of the world you’re from, can play a role.

For example, it’s believed that people with European ancestry may have a higher risk of developing Alzheimer’s than people with African ancestry.

But here’s the fun part. Let’s say someone from a European ancestry has a child with someone with an African ancestry.

The risk for the child will depend on which parent the ε4 gene comes from. If it comes from the African parent, the risk is reduced. If it comes from the European parent, the risk is increased.

So far, just small sample sizes of autopsy studies have been performed, but those small samples are showing some definite differences in the genetic transcripts relating to ancestry. Transcripts are RNA copies of the gene which tell the gene how much protein to make…

Now, we’re getting somewhere.

The number of cells containing APOE ε4 in persons of European ancestry had forty-percent more of these transcripts - meaning forty-percent more incidents when the order to make protein is being given.

I know I got sciency on you but bear with me just a bit more…

Along with APOE ε4, the brains studied in the research showed an increased number of a brain cell called A1 astrocytes. Those little cells are the real cause - believed to be responsible for brain cell degeneration.

Gotcha!

So, what researchers believe is that people from different ancestries who carry this APOE ε4 gene have different genes surrounding APOE ε4, which is what’s making the difference in prevalence.

Wrapping Up

I think anyone who is a caregiver for a loved one with Alzheimer’s Disease, or any form of dementia, secretly worries about needing this same care in the future. And the fear of doing this to someone else stems from knowing how challenging and difficult it is, day-to-day, to provide the care required.

Caregiving is absolutely a labor of love. Some of us are asked to help while others volunteer. I was asked, but I said yes without hesitation.

I already know that one of my daughters has expressed absolutely no desire to care for me when I’m old. She and I are the least alike, so this isn’t a surprise I suppose.

She resents being raised by a single mother who barely got by while going to college and working full-time to raise her and her three siblings. She’s much more like her father than she is like me. That isn’t good or bad, it just is.

Thankfully, I have three other children to choose from, and I suspect I know which one I would be able to rely upon for my care. Still, I hope I don’t do this to her someday…😞