The Inexpensive Heart Drug That Reduces Hospitalizations By 25%

Firstly, no, it’s not about aspirin, and/but let’s quickly touch on that first:

This is actually a complicated one, and we covered it at length in a dedicated main feature. If you want a one-line summary, it’s “chronic low-dose aspirin use can lower overall CVD risk, but does not reduce CVD mortality or all-cause mortality, and you may pay for it with gastrointestinal bleeding, and increased risk of ulcers“.

For a more nuanced explanation, see: Aspirin, CVD Risk, & Potential Counter-Risks

On the other hand, if you are having a heart attack and are waiting for the ambulance that you already called, and have aspirin to hand that you don’t have to go looking for, then it can be good to take a dose then.

For more on that, see: How To Survive A Heart Attack When You’re Alone

In the case of chronic use of low-dose aspirin, not only does it increase the risks of bleeding, especially gastrointestinal bleeding, and ulcers, but also it increases the risk of anemia. Given that anemia also gives the symptom “dizziness”, this is also a significant threat for increasing the incidence of falls in the older population, too, which can of course lead to serious complications and ultimately death.

For the science about this, see: Low-Dose Aspirin & Anemia

Ok, so it’s definitely not aspirin then. What is it?

An addition to the “fantastic four”

Most heart failure treatment relies on 4 kinds of drugs, which thus have been called “The Fantastic Four” (FF), and without even paying royalties to Marvel Comics.

The four drug classes are:

• Beta-blockers
• ARNI, ACE inhibitors, ARBs
• MRA
• SGLT2 inhibitors

That’s a lot of abbreviations, so rather than take up space explaining them all here, we’ll link you to: Heart failure drug treatment: the fantastic four

Researchers (Dr. Dirk Jan van Veldhuisen et al.) did a study of 1,000 people with heart failure treated at 43 centers in the Netherlands, and four that adding low-dose digoxin to standard FF treatment was associated with a 25% average reduction in heart-failure hospitalizations when combined with results from two earlier studies in a meta-analysis.

Additionally, in the 1,000-person study, cardiovascular deaths and worsening heart failure were reduced by 19% among people taking digoxin, although this individual result did not reach statistical significance (another case of how scientists use the word “significant” to refer to the statistical feature, not the extent of the putative change), so take that one with a pinch of (low-sodium) salt.

You may be wondering how low-dose digoxin works: at low doses, digoxin primarily reduces harmful compensatory responses that occur when the heart is struggling, including suppressing stress hormones such as adrenaline. And no, higher doses aren’t that helpful, as while they increase the force of heart contractions, that doesn’t work so well with weakened heart muscle.

There were some problems with stopping digoxin, though: a follow-up study of about 600 participants found that people who had been taking digoxin and then stopped it experienced significantly more problems during the first six weeks than people who had never taken it.

That said, the studies found low-dose digoxin to be safe and relatively easy to use, despite the fact that its use has declined substantially as newer heart-failure treatments became available.

Counterintuitively, this decline in usage is likely mostly because of the cost (or rather, the relative lack of cost):

• digoxin has been used for centuries and costs less than ten cents per day, making it dramatically less expensive than many newer heart-failure medications
• digoxin costing next to nothing makes it very difficult for companies to profit from, so they don’t like it so much, and thus will be less quick to recommend it
  • for this reason, only about 15% of people with heart failure currently receive digoxin, compared with much wider use in the past, despite it still working!

(the same problem also affects funding for new research into old, cheap drugs, including digoxin)

You can read about this research here: Low-dose digoxin in patients with heart failure with reduced or mildly reduced ejection fraction: a randomized controlled trial

And here: Efficacy and Safety of Digitalis Glycosides in Heart Failure: A Meta-Analysis

Want to learn more?

There’s some interesting research that casts some doubts on some of the usefulness of one of the Fantastic Four:

Beta-Blockers: Useless vs Heart Attacks & Worse For Women?

Take care!