Nearly 80 percent of the study participants took one or more of a class of drugs called anticholinergics, including drugs for high blood pressure, asthma, Parkinson's disease and incontinence drugs such as Detrol and Ditropan.
The people who took the drugs had a 50 percent faster rate of cognitive decline compared to those who didn't take any. The researchers considered other risk factors for memory loss, such as age, and still found the link. The researchers found no increased risk for the memory-robbing disorder Alzheimer's in people taking the drugs.
The incontinence drugs were among the most potent and were the most frequently taken of all the anticholinergics in the study. That's why the researchers believe they are driving the memory problems, Tsao said.