Jun 29, 2015

Can you spot Alzheimer's and dementia 18 years before diagnosis?

A new study is suggesting that early symptoms of Alzheimer’s appear up to 18 years before the disease is officially diagnosed.

My mother, Dotty, would have been 99 years old today.

Can you spot dementia 18 years before diagnosis?
The research summary presented below really caught my attention. Why? Because I have often wished that I knew about my mother's impending Alzheimer's disease sooner.

Why? Because I believe it could be possible to delay the onset of Alzheimer's. The key word is delay, I am not saying prevent.

It really is very simple. If a drug were to come on the market that delayed the onset of Alzheimer's by five years,  the number of persons living with Alzheimer's would be cut in half. How? They would simply die before the disease became full blown.

We already have drugs that delay or prevent heart disease. Blood pressure medications and cholesterol medications. It turns out the there is a Catch 22. These drugs help you to live longer. So, if you live to be 85 years old there is about a 42 percent chance that you will be diagnosed with probable Alzheimer's disease or a related dementia.

It is simple. My mother was officially diagnosed when she was 88 years old. What would have happened if she died at 85? We would never have known the difference.

But what if you knew 18 years in advance that you would likely suffer from Alzheimer's disease if you lived long enough?

My guess is you might try and reorient your life and start doing the kinds of things that might delay the onset of Alzheimer's. Real exercise, Mediterranean diet, more socialization, start singing, and believe it or not, there is some evidence that using Google to do searches might help delay the onset of Alzheimer's.

Dotty would have been 99 years old today. Push back Alzheimer's by 5 years, I would have welcomed that.

Of course, maybe that would have meant Dotty would have lived to be 101 years old. I would take that also as is.

Read the research summary below. What are your thoughts?

Alzheimer's Reading Room

Low Scores on Memory and Thinking Tests May Signal Alzheimer’s Earlier than Thought

A new study suggests that errors on memory and thinking tests may signal Alzheimer’s up to 18 years before the disease can be diagnosed.

The research is published in the June 24, 2015, online issue of Neurology®, the medical journal of the American Academy of Neurology.
 “The changes in thinking and memory that precede obvious symptoms of Alzheimer’s disease begin decades before,” said study author Kumar B. Rajan, PhD, with Rush University Medical Center in Chicago. 
“While we cannot currently detect such changes in individuals at risk, we were able to observe them among a group of individuals who eventually developed dementia due to Alzheimer’s.”
  • For the study, 2,125 European-American and African-American people from Chicago with an average age of 73 without Alzheimer’s disease were given tests of memory and thinking skills every three years for 18 years.
  • Twenty-three percent of African-Americans and 17 percent of European-Americans developed Alzheimer’s disease during the study.
  • Those who scored lower overall on the memory and thinking tests had an increased risk of developing the disease.
  • During the first year of the study, people with lower test scores were about 10 times more likely to be diagnosed with Alzheimer’s disease than people with higher scores, with the odds increasing by 10 for every standard deviation that the score was lower than the average.
  • Based on tests completed 13 to 18 years before the final assessments took place, one unit lower in performance of the standardized cognitive test score was associated with an 85 percent greater risk (relative risk of 1.85) of future dementia.
 “While that risk is lower than the same one unit lower performance when measured in the year before dementia assessment, the observation that lower test scores 13 to 18 years later indicates how subtle declines in cognitive function affect future risk,” said Rajan. “A general current concept is that in development of Alzheimer’s disease, certain physical and biologic changes precede memory and thinking impairment. If this is so, then these underlying processes may have a very long duration.

Objective: To examine the relation of performance on brief cognitive tests to development of clinically diagnosed Alzheimer disease (AD) dementia over the following 18 years in a sample of African Americans and European Americans.

Methods: A composite cognitive test score based on tests of episodic memory, executive function, and global cognition was constructed in a prospective population-based sample of 2,125 participants (55% African American and 61% female) aged 65 years and older residing in 4 Chicago neighborhoods. Time before AD dementia diagnosis was categorized into 6 groups corresponding to data collection periods: 0.1–0.9, 1.0–3.9, 4.0–6.9, 7.0–9.9, 10.0–12.9, and 13.0–17.9 years.

Results: Of  2,125 participants without clinical AD dementia, 442 (21%) developed clinical AD dementia over 18 years of follow-up. Lower composite cognitive test scores were associated with the development of AD dementia over the duration of the study. The magnitude of association between composite cognitive test score and development of AD dementia increased from an odds ratio of 3.39 to 9.84 at 0.1–0.9 years, per SD increment.

These associations were consistently larger among European Americans than among African Americans. Performance on individual cognitive tests of episodic memory, executive function, and global cognition also significantly predicted the development of AD dementia, with associations exhibiting a similar trend over 18 years.

Conclusions: Our findings suggest that cognitive impairment may manifest in the preclinical phase of AD dementia substantially earlier than previously established.

Efforts to successfully prevent the disease may well require a better understanding of these processes near middle age,” Rajan said. The study was supported by the National Institute on Aging and the Alzheimer’s Association.

To learn more about Alzheimer’s disease, please visit www.aan.com/patients.

The American Academy of Neurology, an association of more than 28,000 neurologists and neuroscience professionals, is dedicated to promoting the highest quality patient-centered neurologic care.

Cognitive impairment 18 years before clinical diagnosis of Alzheimer disease dementia - https://www.aan.com/PressRoom/Home/PressRelease/1391

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