Viagra, the “little blue pill” used to treat erectile dysfunction (ED), may soon be used to help reduce the risk of developing vascular dementia by boosting blood flow to the brain. 

The vasodilator, whose generic name is sildenafil, has been used to treat ED for decades, although it was first designed to treat angina due to its relative safety. Now the medication has shown that it may eventually be repurposed to conditions in the brain.

The Research and Results

A team of researchers from Imperial College London recruited 75 people with neurological signs of cerebral small vessel disease (CSVD), a risk factor for vascular dementia. CSVD, a common factor driving age-dependent diseases, is an umbrella term used to encompass a variety of conditions that affect the brain’s small blood vessels.

“Small vessel disease is chronic damage to small blood vessels deep inside the brain, resulting in them becoming narrow, blocked, and leaky,” explained Alastair Webb, MSc, one of the study’s authors who serves as a consulting neurologist at Imperial College London. “This damage occurs to some extent in most people as they get older, but it is much more severe in some, often due to having high blood pressure for a long time. The resulting damage may further reduce blood flow to the deep part of the brain resulting in strokes and dementia.”

The participants were given 3 weeks of sildenafil, cilostazol (a treatment for vascular disease), and a placebo, with at least one week between each course. The crossover trial (i.e., every participant is tested on all three pills) allows each person to serve as their own control in order to achieve statistically meaningful results.

The researchers measured four results:

1. Cerebral blood flow (blood supply to the brain)
2. Cerebral pulsatility (stronger pulsations of blood flow to the brain with each heartbeat)
3. Cerebrovascular resistance (resistance to blood flow in the vessels)
4. Cerebrovascular reactivity (reduce responsiveness of blood vessels)

Although the cerebral pulsatility didn’t improve (compared to a placebo) with Viagra, blood flow, cerebrovascular resistance, and cerebrovascular reactivity DID improve (compared to a placebo).

Additionally, Viagra performed similar to cilostazol, but with fewer side effects (e.g., diarrhea).

The study was published in the June 4, 2024 edition of the journal Circulation Research.

Similar findings in previous studies

Although more research is needed, including long-term studies to assess whether Viagra and similar vasodilators can truly reduce an individual’s risk for vascular dementia, previous studies have found similar promising results, including:

• A 2018 published study on aged rats found that Viagra improved cognitive ability and memory.

• A 2020 published study on rats that found that sildenafil could be a key factor in recovering cognitive dysfunction in Alzheimer’s disease.

• A 2021 published study found that sildenafil reduces the incidence of Alzheimer’s disease in humans.

• A 2021 discovery based on insurance claim data for 7.23 million people found that sildenafil was associated with a 69% reduction in the risk of developing Alzheimer’s disease.

MBJ

Wendy Burt-Thomas writes about the brain, mental health and parenting.

Check out the original research:

https://www.ahajournals.org/doi/10.1161/STROKEAHA.122.038265