CLEVELAND — The study in the journal Neurology, the medical journal for the American Academy of Neurology, does not prove that erectile dysfunction drugs actually reduce the risk of Alzheimer's. Rather, it only shows an association.
ED drugs are vasodilators, which dilate blood vessels to help blood flow more easily. They were originally created to treat hypertension (or high blood pressure), but were later found to help men dealing with erectile dysfunction.
The recent study involved 269,725 male participants with an average age of 59 who were newly diagnosed with erectile dysfunction. None had memory issues at study start and they were followed on average for five years.
The study was based on prescription records, and researchers did not know whether participants actually filled the prescriptions and used the drugs. Once researchers adjusted for other factors that could affect, the rate of Alzheimer's disease — such as age, smoking status and alcohol consumption — they found that people who took erectile dysfunction drugs were 18% less likely to develop Alzheimer's than people who did not take the drugs.
The association was strongest in those who were issued the most prescriptions over the study period. However, Dr. Charles Duffy — director of the Brain and Memory Center at University Hospitals Cleveland Medical Center — advises caution regarding preliminary findings.
"Aging is the No. 1 risk factor for Alzheimer's, so it would be very hard to demonstrate a causal relationship between ED drugs and the development of Alzheimer's disease," Duffy said. "So we have to understand that's going to be a hard thing to prove or disprove."
Duffy added that ED drugs could alter brain blood flow, which could increase or decrease the risk of developing Alzheimer's. He notes this was not a randomized control study and there are so many other factors than the ED drugs that may have helped prevent Alzheimer's.
"If the FDA approves ED drugs for Alzheimer's, then we'll have credible evidence," he stated.
Meanwhile, metabolic syndrome — which is the combination of obesity, diabetes, hypertension, and high cholesterol — is a known risk factor for triggering the development of Alzheimer's. Getting those things under control is a good start to preventing the disease.