More evidence that certain prescription medications can increase a person's risk for dementia.
This newest study from Group Health and the UW also shows that risk applies to some common over-the-counter drugs and it may not go away, even after a person stops taking the medications.
These include older antidepressants, bladder control drugs, but also mainstream medications like Benadryl, Dramamine and night-time sleep aids. The medications are all part of a class called anticholinergics.
"They have the long term effect if you take a lot of them over and over again of increasing your chances of getting dementia later on in life," according to Dr. Eric Larson, study co-author with Group Health.
He said side effects like confusion and lethargy used to be considered temporary. This study is the first to show otherwise. Another concern?
"Older adults may be more than one anticholinergic medication," said UW Professor and Vice Chair of Pharmacy, Shelly Gray, the first author of the study.
The higher the total dose, the longer the time, the greater the risk.
How to reduce that risk?
"For most conditions there are alternatives available," she said.
Prozac- type (SSRI) antidepressants are a better choice, so is Claritin for allergies.
However, there is no substitute drug to control overactive bladder.
"So our advice is just to use the lowest effective dose, to monitor to make sure it's working and if it's not working to discontinue the therapy," she said.
Dr.Larson says it's all about controlling what you can to avoid dementia.
"Our research is to say can we take this disease which seems so inevitable, if you are 90,95,100 and simply move it later and later in life so if you live that long, it's closer to when you die or if you don't live that long, you die without it."
Study authors say elderly patients should stop taking these over-the-counter drugs, but talk to your healthcare provider first before discontinuing any prescription medications.
Occasional use of these medications did not pose a problem. Researchers only looked at patients over the age of 65. Dr. Larson says younger brains are not as vulnerable.
Here is a list of those medications.
The study, which appears in the current issue of JAMA Internal Medicine, was a collaboration between Group Health, UW School of Pharmacy and UW Medicine.
Researchers tracked nearly 3,500 Group Health patients for more than seven years. None had dementia when they entered the study, but 797 of them went on to develop it.