Taking erectile dysfunction (ED) drugs like Sildenafil Accord to help with impotence could help men with stable coronary artery disease live longer and have less risk of having a new heart attack.

This is according to new research carried out by the Karolinska Institute in Sweden, and published in the Journal of the American College of Cardiology, revealing that men who received PDE5 inhibitors lived longer and were less likely to have a new heart attack, balloon dilation, bypass surgery or heart failure than people who took alprostadil.

Impotence can be an early sign of cardiovascular disease in healthy men and erectile dysfunction can be treated with PDE5 inhibitors like Viagra or Cialis, which are taken orally before sex. They work by inhibiting the enzyme phosphodiesterase5 (PDE5), which increases blood flow to the penis.

Because these inhibitors decrease blood pressure, they aren’t recommended for men with coronary heart disease because of the heart attack risk. But in 2017, it was found that men who have already had a heart attack are able to tolerate the drug well, finding that it can even prolong life expectancy, as well as protecting against new infarctions and heart failure.

This new study compared the effect of PDE5 inhibitors and alprostadil in men with stable coronary artery disease. It was found that the protection against heart attack, heart failure and so on was dose dependent, so the more frequent the dose of the inhibitor, the lower the risk.

Lead author of the study Martin Holzmann said: “The risk of a new heart attack is greatest during the first six months, after which we consider the coronary artery disease to be stable.

“This [study] suggests that there’s a causal relationship, but a registry study can’t answer that question. It is possible that those who received PDE5 inhibitors were healthier than those on alprostadil and therefore had a lower risk.

“To ascertain whether it is the drug that reduces the risk, we would need to randomly assign patients to two groups, one that takes PDE5 and one that doesn’t. The results we have now give us very good reason to embark on such a study.”

Interestingly, Viagra initially started off life as a potential drug to treat angina, before it was used as the main way to treat ED. Since then, it has also been used to help treat a variety of heart issues, such as pulmonary hypertension – so it’s a very effective drug, indeed.

This process is known as drug repurposing or repositioning, with advances in medical research making it possible to use existing medications to treat other conditions.

The process involves initial theories and lots of early research to try and treat various medical conditions. Once a candidate is found, the drugs are tested in clinical trial subjects to make sure they’re safe and effective.