Especially in the elderly who are at high risk of developing Alzheimer’s disease.
Anxiety, urinary incontinence, allergies: the drugs that are prescribed are the most dangerous
Anticholinergic drugs block the action of acetylcholine, a chemical messenger that controls many automatic body functions and plays an important role in memory and attention. Doctors prescribe these drugs for different conditions. With urinary incontinence, overactive bladder, chronic obstructive pulmonary disease (COPD), seasonal allergies and depression.
However, in the last decade there is growing evidence that anticholinergics may increase the risk of dementia in older adults. Researchers at the University of California, San Diego have linked anticholinergics to mild cognitive impairment, which can lead to dementia, including Alzheimer’s disease.
The risk is particularly increased in people who have symptoms of Alzheimer’s disease in their cerebrospinal fluid and in those who have an increased genetic risk of developing the disease. The interaction between anticholinergic drugs and Alzheimer’s risk factors is doubly effective. In the first case, the markers for Alzheimer’s disease show that the damage begins in a small area of the brain called the basal forebrain, which produces acetylcholine. Then, in the second case, anticholinergic drugs further reduce the brain’s acetylcholine stores. This combined effect has a very important effect on human thinking and memory.
47% increase in the risk of cognitive impairment
The study included 688 people who participated in the Alzheimer’s Disease Neuroimaging Initiative. The participants had an average age of 74, and none showed signs of cognitive or memory problems at the start of the study. Three-quarters of them were taking at least one type of drug, with an average of 4.7 anticholinergic drugs per person. There were no differences in genetic risk factors between people who took anticholinergics and those who did not.
However, symptoms, the total number of medications and heart problems are greater in people taking anticholinergics. We therefore considered these variables in all subsequent analyses. From the start of the study, participants took annual cognitive tests for 10 years.
Among those taking at least one anticholinergic, there was an overall 47% increased risk of mild cognitive impairment compared to those who did not take it. Those who take these drugs and who are at genetic risk of developing Alzheimer’s disease are more than 2.5 times more likely to have mild cognitive impairment than those who do not take the drug and have no genetic risk. Participants who had Alzheimer’s antibodies in their cerebrospinal fluid at the start of the study and who took anticholinergics were almost 5 times more likely to show signs of mild cognitive impairment.
The results of the study were published in the journal Neurology.