New research from University College London suggests that men who take erectile dysfunction pills may have a reduced risk of developing Alzheimer’s disease.
Although it does not prove that erectile dysfunction drugs, such as Viagra, reduce Alzheimer’s risk, the study of over 250,000 men does show an association that warrants further research and could help develop novel treatments.
The leader of the study, Ruth Brauer, PhD, of the University College London, explained: “Although we’re making progress with the new treatments for Alzheimer’s disease that work to clear amyloid plaques in the brain for people with early stages of the disease, we desperately need treatments that can prevent or delay the development of Alzheimer’s disease.
“These results are encouraging and warrant further research.”
How do erectile dysfunction pills work?
Erectile dysfunction medications were initially developed to treat high blood pressure. The most common type of erectile dysfunction pills belongs to a class of drugs called phosphodiesterase type 5 (PDE5) inhibitors.
These include well-known brand names like Viagra (sildenafil), Cialis (tadalafil), Levitra (vardenafil), and Stendra (avanafil).
Erectile dysfunction pills work by increasing blood flow. During sexual arousal, the body releases a chemical called nitric oxide, which signals the relaxation of smooth muscles in the penis.
This allows increased blood flow into the spongy tissues of the penis, causing an erection. PDE5 is an enzyme that breaks down nitric oxide. By inhibiting PDE5, these medications effectively amplify the effects of nitric oxide, leading to improved blood flow.
Now, research suggests these drugs can potentially be leveraged to reduce the risk of Alzheimer’s disease among men.
Effects of Alzheimer’s risk
The research included 269,725 male participants, averaging 59 years old and newly diagnosed with erectile dysfunction.
The participants, initially free of memory or thinking issues, were tracked for about five years. The study compared the 55% of participants prescribed erectile dysfunction drugs to the 45% without prescriptions.
Alzheimer’s development rates
Throughout the study, 1,119 individuals developed Alzheimer’s disease. Among those taking erectile dysfunction drugs, 749 developed Alzheimer’s, indicating a rate of 8.1 cases per 10,000 person-years.
Person-years encompass both the number of participants and the duration each person remained in the study. Conversely, among non-users, 370 developed Alzheimer’s, yielding a rate of 9.7 cases per 10,000 person-years.
After adjusting for various factors such as age, smoking, and alcohol consumption, researchers found that erectile dysfunction drug users were 18% less likely to develop Alzheimer’s compared to non-users.
The study highlighted a more robust association between erectile dysfunction drug usage and reduced Alzheimer’s risk among those receiving the most prescriptions over the study period.
Despite positive findings, Brauer emphasised the need for further research: “More research is needed to confirm these findings, learn more about the potential benefits and mechanisms of these drugs and look into the optimal dosage.
“A randomised, controlled trial with both male and female participants is warranted to determine whether these findings would apply to women as well.”
