Men who take Viagra may reduce their risk of Alzheimer's disease, a study suggests. In a study of more than 260,000 men, those who took these drugs were 18 percent less likely to develop the disease that causes dementia.
Men who take Viagra may have a lower risk of developing Alzheimer's PHOTO Shutterstock
By attacking a substance called beta-amyloid, which accumulates in the brains of people with Alzheimer's, they have the potential to change the way the disease is treated, reports the BBC.
But scientists are still looking for existing drugs that could prevent or delay the onset of the disease.
Drugs like Viagra were originally designed to treat high blood pressure and angina pectoris. They act on a cellular signaling messenger that may also be linked to memory.
They are also known to affect the activity of brain cells, and animal research suggests that they have some protective effect on the brain.
Regular use of the drug could have a greater impact
In the new study in Neurology, researchers at University College London analyzed the prescription records of thousands of men with erectile dysfunction, comparing those who were given the drugs and those who were not.
Over the next five years they found 8.1 cases of Alzheimer's per 10,000 people in the group prescribed the drugs and 9.7 cases in the group not taking them.
Men who received the most prescriptions for erectile dysfunction drugs were the least likely to develop Alzheimer's, suggesting that regular use of the drug may have a greater impact on the disease.
The researchers say their study doesn't show that the drugs themselves reduce Alzheimer's risk, but it could point to a new direction for research.
The study's lead author, Dr. Ruth Brauer, said: “More research is needed to confirm these results, to learn more about the potential benefits and mechanisms of these drugs, and to analyze the optimal dose.”
The researchers also want to conduct a study in both women and men to see if the drug has any impact.
It's “an excellent study”
There are many factors that could cause the disease. The study adjusted its results for some of them, including age, underlying health conditions, other medications taken, and whether the participant was a smoker or not.
“This study does not conclusively prove that erectile dysfunction drugs reduce the risk of Alzheimer's, but it does provide good evidence that this type of drug deserves further study in the future.”said Professor Tara Spiers-Jones, from the University of Edinburgh and president of the British Neuroscience Association.
Dr Francesco Tamagnini, a neurophysiologist at the University of Reading, said it was an “excellent study” but that more hard evidence was needed on how the drug affects the brain.
“It may be that it exerts a therapeutic effect by directly affecting neurons (if the drug is able to cross the blood-brain barrier) and/or by increasing blood flow, but both hypotheses need to be tested“, he said.