Are There Subtypes of Dementia?

As Alzheimer’s disease and related dementias reach epidemic proportions with no cure on the horizon, researchers, people living with the disease and their families are struggling to find an explanation for the lack of treatment options.Are There Subtypes of Dementia?

A new study suggests that it may be because Alzheimer’s is actually not one single disease but exists in three separate subtypes, which would mean separate treatment options tailored for each subtype. Learn more about the new study and the implications of dementia existing in three different forms.

Are There Subtypes of Dementia? A Rising Suspicion Among Researchers

It’s no secret that Alzheimer’s drug trials have been troubled. Last year, it was reported that over 99% of all potential drugs for the disease have failed over the last 10 years with only one medication available to alleviate some symptoms of the disease since 2004.

Most drug trials revolved around drugs targeting beta amyloid build up in the brain. In fact, more than 65% of all trials from 2002-2012 involved drugs targeting beta amyloid. More recently, drug developers have also been testing medications targeting another protein in the brain, tau, which is also a crucial protein in the development of dementia.

The unfortunate truth behind the high percentage of failed drugs and failed experimental studies lies the fact that researchers do not know exactly what causes Alzheimer’s. Dr. Dale Bredesen, professor of neurology at the University of California, Los Angeles believes this may be because there are subtypes to Alzheimer’s stating:

“Because the presentation varies from person to person, there has been suspicion for years that Alzheimer’s represents more than one illness.”

Bredesen, who is also the founding president of the Buck Institute for Research on Aging, recently conducted a study suggesting that Alzheimer’s is actually not one single disease, but instead exists in three different subtypes that he calls inflammatory, noninflammatory and cortical.

Study Suggests Three Different Subtypes of Alzheimer’s

Bredesen and his team performed regular metabolic testing on 50 people living with Alzheimer’s  and dementia over the course of two years. Researchers used metabolic testing to search for biomarkers (or indicators of Alzheimer’s) in those participants exhibiting symptoms.

The study revealed three separate types of biomarkers, which could mean three subtypes of the disease. Participants with the inflammatory subtype had high levels of C-reactive proteins, produced by the liver, which increase when the body experiences inflammation. In the noninflammatory subtype there are other metabolic abnormalities but no inflammation. The third type ,which Bredesen calls cortical, is actually correlated with a substantial zinc deficiency.

Because Alzheimer’s is classified as a neurodegenerative condition, doctors don’t conduct thorough metabolic testing on patients even though metabolic conditions, like obesity, inflammation, hypertension and high glucose levels have been linked to the disease. Bredesen is careful to note in his study that this merely shows a correlation and not causation since many of the metabolic conditions linked to Alzheimer’s are increasing in developed countries.

Bredesen noted the importance of the subtypes stating:

“The important implications of this are that the optimal treatment may be different for each group, there may be different causes, and, for future clinical trials, it may be helpful to study specific groups separately.”

Do you believe that our difficulty in finding a cure  or treatment for dementia could be because there are separate types of the disease? Share your thoughts with us in the comments below.

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Please leave your thoughts and comments

  • Lonna Whiting

    My mother was diagnosed with early-onset dementia at age 61. We were told by a nurse educator at Mayo Clinic in Rochester, Minn., that there are likely a hundred or more “types” of dementia. We have no family history of the disease.

    • Esther

      My mother at 83 has slowly been losing her memory for 12 years .. lack of sleep through life , diet, overweight, type2 diabetes and loves salt.
      Improved diet seems to have slowed the decline .. with insulin half previous levels .

  • Sarala Balachandran

    My husband 76 years showing impairment of memory. He talks ok. If he says something after two minutes he forgets. He keeps things and he cannot find. Talking has become very less. He is on Cogmentin 5 for the last six months. No family history of this disease.

  • Ali Sa

    Could you please cite the claims on your article? This can help researchers to get more benefits, save more times and your report gets more hits.

    • caitlinburm

      Hi Ali,

      Which study are you referring to? The studies that we cite on are always linked within the blog content, and the specific study that we are reffering to when discussing the three subtypes of Alzheimer’s disease in this blog can be found above. Here it is again:

      Thank you for your inquiry.

  • Diane

    I don’t know if there is so much of sub types but also the fact that they are all different.. I have found that when I read comment from people that Alzhimiers get opposites mixed up cats r dogs dogs r cats. Boys r girls girls boys etc.. Some have a common that if they have been mild mannered throughout life they are now aggressive. I took care of my Mom one on one for four years .. In talking to others also I was going to try hepa as I agree w the brain build up.. But my Mom had fallen and had a tasty rest home rehab night mare before I brought her home on hospice.. “I am My Parent Keeper ” diane headley sellers

  • Cher

    I would like to add my thoughts to the conversation. My husband was diagnosed with Dementia after an MRI scan nearly three years ago. As time goes on and he does not exhibit the normal deterioration associated with the disease I wonder if in fact the diagnosis was correct.

  • sal

    My mother started to sound “old” when she was around age 75. It would be a good idea to discuss how changes in the voice occur as a symptom of Alzheimer’s. We do not have a diagnosis for my mother, she has refused to go to a neurologist and changes the subject when I suggest she go see one. Also she has good days and bad days, however she also has Crohn’s disease and has lost over 30 lbs of body weight in the last year and a half, she was also losing blood from her bowel disorder and became anemic. She was hospitalized several times in the past 2 years for bowel obstructions so perhaps malnutrition has something to do with her mental confusion (which comes and goes). Doctors are at a loss about how to treat her intestinal disorders. She previously was diagnosed with diverticulosis. She will be 80 on her next birthday. She went from a healthy 140-150 lbs down to 120 lbs. She looks frail and unhealthy.

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