In December, the University of Texas Health Science Center, in Houston, reported a study that found people who live in areas with high rates of Alzheimer’s disease (AD) are more likely to develop dementia over time.
More than two-thirds of the participants were found to be suffering from the disorder and nearly half were under 65.
As the National Institutes of Health (NIH) reports in its Alzheimer’s Disease Facts and Figures report, more than 70% of AD patients are older than 65, with nearly 90% of them being found to have the disease.
“In the United States, the incidence of AD has increased by over 1,100% since 1965, and we know from previous research that older people are at greater risk for developing AD, because they have less genetic material and a smaller genetic burden,” Dr. Richard A. Czuba, the lead author of the report, told The Atlantic.
A study from the National Institute of Neurological Disorders and Stroke found that about a quarter of adults who developed AD had experienced a mental health problem at some point during their lifetime.
A second study found that nearly a third of people diagnosed with AD had had a mental illness at some time in their lives, including depression, anxiety, alcohol abuse, substance abuse, and drug abuse.
As the number of people with AD increases, the number and severity of the mental health problems and illnesses associated with the condition continue to rise.
What does the new report say?
As the study notes, there is evidence that dementia in older adults is associated with increased risk for mental health conditions, including anxiety, depression, and alcohol and drug use.
More specifically, the researchers found that those with AD were more likely than people without the disease to report symptoms of anxiety, anxiety-related symptoms, depression or alcohol or drug use, and less likely to have had an episode of anxiety-like symptoms, such as crying or shaking, during the past year.
The study also found that the incidence rate of dementia in people with dementia was higher in the United Kingdom than in the U.S. In fact, the study found more people in the UK had been diagnosed with dementia compared to people in other countries.
There are some important caveats to the findings, however.
One is that people with some forms of dementia are more prone to developing other mental health issues.
For instance, the people in Czubas study who had AD had an elevated risk of having had a diagnosis of depression or anxiety in the past 12 months.
Another study found a higher prevalence of dementia among people with ADHD in people who had never had ADHD, and a higher risk of dementia and depression in people over 65 years of age.
Still, the results are encouraging, and the research suggests that the number one risk factor for dementia in the older population is an elevated incidence of stress.
How do we prevent dementia?
The authors of the study say that a better understanding of the mechanisms of Alzheimer and AD may provide a more effective way to prevent the onset of dementia.
For instance, a recent study in the journal Nature Neuroscience found that an increased number of connections between brain cells in the hippocampus—a structure associated with memory—are linked to the risk of developing Alzheimer’s.
This study also suggests that neurogenesis is an important step in the development of memory, with increased levels of neurogenes in the brain in people under age 35, and people who have never had Alzheimer’s being more likely, or at greater risks, of developing dementia.
The study suggests that it may be possible to alter the levels of neurotransmitters that promote neurogenetic processes, such that certain chemicals may enhance or suppress the formation of these neural connections.
In particular, a study published in the Journal of Alzheimer Disease Research found that increasing the levels in the prefrontal cortex, a region of the brain linked to emotion, could decrease the risk for dementia.
Another possibility is to develop drugs that block the production of certain neurotransmitter chemicals, such with serotonin and dopamine, which have been linked to Alzheimer’s and depression.
Other studies are also suggesting that neurodegeneration in the elderly is a factor in Alzheimer’s development.
In a study from Harvard Medical School, researchers found a link between brain aging and an increase in a protein known as the APP gene, which is linked to increased risk of Alzheimer-like disease.
In addition, in a study in PLOS Genetics, a team of scientists found that a person’s risk of experiencing cognitive decline was related to their risk of AD.
“These findings may provide clues about how brain aging contributes to Alzheimer disease and other neurodegenative diseases,” the researchers wrote in their study.
“However, more work is needed to understand the molecular mechanisms of these relationships and to identify mechanisms of protective effects of cognitive training on cognitive decline.”
What do we know about cognitive training?
In a previous study published this month in the Proceedings of