Cleveland Clinic researchers found sildenafil, which goes by the name brand Viagra, is associated with a 69 percent reduced likelihood of developing Alzheimer's, according to findings published Dec. 6 in Nature Aging.
The research team used a large gene-mapping network to integrate genetic and other data to evaluate which of over 1,600 FDA-approved drugs may be an effective treatment for the disease. They focused on drugs that target both beta amyloid and tau proteins, two hallmarks of Alzheimer's.
"Sildenafil, which has been shown to significantly improve cognition and memory in preclinical models, presented as the best drug candidate," said Feixiong Cheng, PhD, lead study author and researcher at Cleveland Clinic's Genomic Medicine Institute.
Using a large database of claims from more than 7 million people, they then analyzed the relationship between sildenafil and Alzheimer's disease by comparing those who used the drug to those who did not. Sildenafil users were 69 percent less likely to develop Alzheimer's than non-users after six years of follow-up, findings showed.
Using stem cells, the team also developed an Alzheimer's patient-derived brain cell model and found the drug increased brain cell growth and targeted tau proteins.
Researchers emphasized their findings did not establish a causal relationship between sildenafil and Alzheimer's and that randomized clinical trials are needed to better understand sildenafil's potential clinical benefits for the disease.