Anticholinergic drugs have been found to be associated with an increased risk of cognitive decline, according to a new study published in Neurology. This class of drugs is commonly prescribed for many conditions, including allergies, colds, urinary incontinence, overactive bladder, high blood pressure, Parkinson’s disease, and depression.
Researchers found a risk of cognitive decline, particularly in people who have genetic risk factors for Alzheimer’s disease or markers of this condition. This type of drug has approximately 100 variations that are in widespread use across the United States. Some require a prescription, but others may be purchased over the counter.
The study included 688 people with an average age of 74 who had no cognitive difficulties at the start of the study. All participants were required to report if any anticholinergic drugs were taken within three months of the beginning of the research or at least once a week for more than six months. Cognitive tests were given to each participant once a year for ten years.
Over the 10 years, one-third of the participants reported taking anticholinergic drugs, with an average of 4.7 anticholinergic drugs taken per person. This included variations of the drugs called metoprolol, atenolol, loratadine, and bupropion, which were the most common.
It was found that of the 230 people who were taking anticholinergic drugs, 117 people later developed mild cognitive impairment. This was compared to 192 people who were not taking any variation of the drug. After adjusting for a history of cardiac problems, medications, and depression, it was concluded that individuals taking at least one anticholinergic drug had a 47% increased risk for developing mild cognitive impairment. For individuals taking a higher dose of anticholinergic drugs, the risk increased.
Prevent Negative Consequences
“Our findings suggest that reducing the use of anticholinergic drugs before people develop any cognitive problems may be an important way to prevent the negative consequences of these drugs on thinking skills, especially for people who have an elevated risk of developing Alzheimer’s disease,” said study author Lisa Delano-Wood. “Future studies are needed to see if indeed stopping the use of these drugs could lead to a reduction in mild cognitive impairment and Alzheimer’s disease down the road.”
Researchers also examined patients to find a relationship between participants with cognitive decline and those who had biomarkers for Alzheimer’s disease in their cerebrospinal fluid or those who had a genetic risk for Alzheimer’s disease. It was found that participants with biomarkers for Alzheimer’s disease in their cerebrospinal fluid who were taking anticholinergic drugs were four times more likely to later develop mild cognitive impairment compared to people who were not taking the drugs and did not have the biomarkers. Similarly, participants who showed a genetic risk for Alzheimer’s disease and took anticholinergic drugs were about 2.5 times as likely to develop mild cognitive impairment later.
People who are taking anticholinergic medications are encouraged to speak to their doctors about the risk factors for memory problems. These findings offer a possible change in the precision medicine approach as physicians can more carefully consider and prescribe medications for people depending on their risk profile for neurodegenerative disorders like Alzheimer’s disease.