Can taking certain drugs increase your risk for dementia? That's a question that has dogged anticholinergic medications, which are commonly used to treat an array of conditions, including asthma, depression, heart problems and urinary incontinence. And for some people, the answer is yes, says Dr. Suzanne Schindler, an assistant professor of neurology at the Knight Alzheimer Disease Research Center, which is part of the Washington University School of Medicine in St. Louis.
Many medications, both over-the-counter and prescription, can cause cognitive problems that increase the risk for dementia, Schindler says. "For example, people who take anticholinergic medications may notice that they become confused or groggy," she says. Some patients take these medications, which can impair memory and thinking, for years, and the drugs may lead to more severe, chronic problems like dementia.
"These patients may not even realize the medications are causing cognitive problems," Schindler explains. "When an individual's cognitive abilities decline and they are unable to maintain their typical daily activities, the medical term for this is dementia."
Dementia describes a set of symptoms that can include memory loss and difficulties with thinking, problem-solving, planning or organizing or using language. The most common cause of dementia in older people is Alzheimer's disease, which causes specific brain changes.
Overall, about 5.8 million people in the U.S. have Alzheimer's disease, most of them age 65 or older, according to the Alzheimer's Association.
Common signs and symptoms of dementia caused by Alzheimer's disease include:
-- Memory loss that disrupts daily life.
-- Challenges in planning or solving problems.
-- Difficulty completing familiar tasks.
-- Confusion with time or place.
-- Trouble understanding visual images and spatial relationships.
-- New problems finding the right words when speaking or writing.
-- Misplacing things and losing the ability to retrace steps.
-- Decreased or poor judgment.
-- Withdrawal from work or social activities.
-- Changes in mood and personality.
Research suggests that taking various types of commonly used drugs, including anticholinergic medications, could raise a person's risk for developing dementia. For example, a large study published in JAMA Internal Medicine in June 2019 found taking these drugs was associated with an risk for developing dementia:
-- Anti-Parkinson's disease medication.
-- Anti-psychotic drugs.
-- Medication for an overactive bladder.
-- Anti-epileptic drugs.
The study involved 58,769 patients with a diagnosis of dementia in England and 225,574 control individuals age 55 or older. "These findings highlight the importance of reducing exposure to anticholinergic drugs in middle-aged and older people," the researchers wrote.
It's important to note that anticholinergics probably don't cause the brain changes associated with Alzheimer's disease, Schindler says.
"Anticholinergics change brain chemistry, but they probably don't change the structure of the brain," she says. However, she adds that anticholergenic medications may make the symptoms of Alzheimer's disease worse.
The most common anticholinergic drugs fall into three types, says Kajua B. Lor, an associate professor in the clinical sciences department at the Medical College of Wisconsin in Milwaukee.
These types of anticholinergic drugs are:
-- Certain types of antihistamines.
-- Some medications used to treat an overactive bladder.
The greater the amount of anticholinergic drugs you take and the longer you take them, the greater risk they pose for dementia, says Dr. Babak Tousi, who heads the clinical trials program at Cleveland Clinic's Lou Ruvo Center for Brain Health.
If you're taking or considering an anticholinergic drug, experts recommend that you:
-- Talk to your primary care physician and pharmacist.
-- Review your medication annually.
-- Discuss ways to minimize use of anticholinergic drugs that can cause cognitive symptoms.
-- Stop taking medications that are no longer useful.
-- Don't dismiss all anticholinergic medications.
Talk to your primary care physician and pharmacist. Ask your primary care doctor and your pharmacist whether any anticholinergic medications you've been prescribed could increase your risk for dementia, Tousi suggests. Talk through the potential risks and ask about alternative, safer medications. When your doctor prescribes a new medication, ask if it can affect your thinking.
Review your medication annually. Tousi advises patients to review what medications they're taking each year with their doctor, a pharmacist or a geriatrician, especially if there are any concerns about cognition or thinking. If an anticholinergic medication you're taking isn't as beneficial as before, ask your doctor whether it can be discontinued or if the dose can be reduced.
Stop taking medications that are no longer useful. It's not unusual for some patients to still take anticholinergic medication for, say, an overactive bladder even after they've become fully incontinent, Tousi says. There's no need to keep taking a medication that's no longer beneficial.
Discuss ways to minimize use of anticholinergic drugs that can cause cognitive symptoms. "If possible, use medications that don't cause cognitive side effects," Schindler says. For example, instead of taking Benadryl, an anticholinergic, for allergies, Schindler typically recommends other, non-anticholinergic medictions like Claritin. To treat pain, also consider non-pharmacological treatments, like physical therapy or massage.
Don't dismiss all anticholinergic medications. It's important to keep in mind that all medications have potential benefits and side effects, Schindler says. "Anticholingergics are used because they can be very helpful to patients with a variety of problems," she says. "Some patients may have no major side effects from the anticholinergics, while other patients may have major problems. Therefore, it's important for patients to talk to their physicians about the benefits and side effects they've noticed from anticholinergics and other medications, so that their physician can find the treatment plan that's best for them."