Like depression, anxiety increases the risk of developing Alzheimer’s disease, due to its symptoms and impact on the brain. Here’s what you need to know.
Sure, your run-of-the-mill, every day stress and worry may be associated with dementia. But just as depression bears a well-known link to dementia, including Alzheimer’s disease, so too does a clinically diagnosable anxiety disorder.
Anxiety disorders are characterized by excessive fear and anxiety that disrupt people’s daily lives, including Generalized Anxiety Disorder (GAD), PTSD, panic disorder, agoraphobia, and social anxiety disorder. These are very common. In fact, they affect 30 percent of adults at some point in their lives. In addition, women are more than twice as likely than men to develop an anxiety disorder at some point. Meanwhile, of the 30 million people living with Alzheimer’s disease worldwide, two thirds of those diagnoses are women.
For those with a high risk of Alzheimer’s and with neuropsychiatric disorders like anxiety, it helps to know the facts of your overall risk.
Why is anxiety considered a risk factor for Alzheimer’s disease?
Anxiety is considered a risk for Alzheimer’s disease in particular because of its impact on the brain. Research has found associations between anxiety and the aggregation of various harmful proteins in the brain — not to mention brain shrinkage, which can lead to cognitive deterioration. In fact, scientists at Brigham and Women’s Hospital found that increased anxiety comes with higher levels of beta-amyloid — a toxic protein that forms plaques in the brains of people with Alzheimer’s disease.
“Rather than just looking at depression as a total score, we looked at specific symptoms such as anxiety,” explains a primary author of the study Nancy Donovan, M.D. “When compared to other symptoms of depression such as sadness or loss of interest, anxiety symptoms increased over time in those with higher amyloid beta levels in the brain.”
The repetitive negative thinking associated with anxiety also contributes to Alzheimer’s risk. A 2020 study by researchers at University College London found repetitive negative thinking (RNT) can lead to cognitive decline and more deposits of amyloid and tau proteins.
Lead author of the study, Dr. Natalie Marchant at UCL Psychiatry, explains: “We propose that repetitive negative thinking may be a new risk factor for dementia as it could contribute to dementia in a unique way.” While depression and anxiety in midlife are already risk factors for dementia, Marchant also notes: “Certain thinking patterns implicated in depression and anxiety could be an underlying reason why people with those disorders are more likely to develop dementia.”
As Dr. Richard Isaacson, a neurologist, and director of Weill Cornell University’s Alzheimer’s Prevention Clinic, told Being Patient in a Live Talk, this repetitive negative thinking can “fast forward amyloid and tau deposition, which fast forwards shrinkage of the memory center of the brain.”
Is anxiety a symptom of cognitive impairment — or a cause?
Personality changes are often reasons people seek out a cognitive assessment, including increased anxiety. As Dr. Rebecca Chopp recalls in a Live Talk, it wasn’t the early signs of cognitive decline that she noticed but increased social anxiety. She recalls that as she and her husband looked back, “there were signs developing, not cognitive so much, in my case, but social anxiety, not wanting to go to events, and being more tired.” Chopp explains that at events, she would find excuses not to go because it was “too loud” or there would be “swarms of people,” and “I would find excuses not to go… and that was happening two or three times a week.”
While anxiety may lead to potentially developing Alzheimer’s, the stress of mild cognitive impairment could also cause the symptoms to manifest. As Dr. Maria Vittoria Spampinato explains regarding a Medical University of South Carolina study linking anxiety to cognitive impairment, whether anxiety was a cause of a faster progression of Alzheimer’s or a consequence. She notes, “We don’t know yet if the anxiety is a symptom — in other words, their memory is getting worse, and they become anxious — or if anxiety contributes to cognitive decline.”
This particular study studied the progression of developing Alzheimer’s in participants with Alzheimer’s. As another author of the study, Jenny L. Ulber, explains, “Mild cognitive impairment patients with anxiety symptoms developed Alzheimer’s disease faster than individuals without anxiety, independently of whether they had a genetic risk factor for Alzheimer’s disease or brain volume loss,”
However, screening anxiety in older adults could be helpful for screening for cognitive impairment and help slow down the process. Spampinato notes, “Middle-aged and elderly individuals with high levels of anxiety may benefit from intervention…whether it be pharmacological or cognitive behavioral therapy, with the goal of slowing cognitive decline.”
What if you have depression and anxiety?
Many people worldwide suffer from both depression and anxiety. Estimates show that 60% of those with anxiety also have symptoms of depression. When you are dealing with both of these symptoms, it can actually increase your risk of developing dementia. A study with the American Academy of Neurology finds that among people who develop Alzheimer’s disease, anxiety can speed the onset of dementia symptoms by three years and depression by two years. For people with anxiety and depression, the onset can happen even faster.
“We hypothesize that the presentation of depression in some people could possibly reflect a greater burden of neuroinflammation,” lead author Dr. Zachary A. Miller of the University of California, San Francisco, explains. This is because study participants with depression were more likely also to have an autoimmune disease, and those with anxiety were more likely to have a history of seizures. Both of these could cause neuroinflammation, which can also increase the possibility of Alzheimer’s.
In the past, researchers have also investigated anxiety’s link to reduced brain volume. Miller’s team, however, predicts that anxiety might lead to greater “neuronal hyperexcitability,” which is when the brain’s networks are overstimulated.
Whether it’s related to brain shrinkage or your brain’s overstimulation, having both depression and anxiety can boost your risk overall.
Do anxiety meds cause cognitive decline?
While taking medication for anxiety can benefit people dealing with negative symptoms like excessive worry, some medicines for anxiety and insomnia may increase Alzheimer’s risk. Research from the New England Journal of Medicine finds that Xanax, Ativan, Valium, and other benzodiazepines could increase Alzheimer’s risk. While people can use these types of medicine as needed or once a month, taking them more frequently can lead to cognitive decline.
“Just as with opioids, some patients benefit from long-term use of benzodiazepines,” experts from the study noted, “But even in low-risk patients, it is best to avoid daily dosing to mitigate the development of tolerance, dependence, and withdrawal.”
In addition, anticholinergic drugs may also lead to increased dementia risk. Researchers at the University of East Anglia in the U.K. found that these drugs increased a person’s risk of developing dementia by up to 30 percent. People typically use these medications for depression, Parkinson’s, and loss of bladder control. However, since depression and anxiety drugs do have some overlap, it’s a good idea to check with your doctor about the risks of these drugs.
Of course, if medications help reduce the anxiety symptoms that lead to Alzheimer’s, they could still be beneficial. What’s important is to evaluate your level of risk and speak to your doctor about the best option for you.
Does management of anxiety symptoms help reduce dementia risk?
In general, managing anxiety symptoms, whether medications, lifestyle changes, or a combination of the two, can be helpful. Reducing your stress level could lower your risk for cognitive decline and Alzheimer’s. In addition, tackling the feelings of loneliness and isolation that come with anxiety provides good outcomes for your overall health.
Research finds that social isolation has a dramatically increased risk of developing dementia. In addition, studies have found this risk increases by as much as 40 percent. Treating your anxiety and reducing your overall loneliness could lead to more significant health benefits and slow the risk of dementia.
Researchers have found that treating depression and anxiety can improve cognitive functioning. Robert Stern, Ph.D., of the BU Alzheimer’s Disease Center behind the study, explains, “The implication is that successfully identifying and providing effective treatment for these neuropsychiatric symptoms, including depression, may potentially improve or maintain cognitive functioning in many older adults.”
While anxiety symptoms can impact your Alzheimer’s risk, treating these symptoms can improve your overall brain health.