Heart Failure - Could testosterone hold the key?

As healthy men age, there is a fall in testosterone and alongside this there is a decrease in muscle mass, muscle strength and lower extremity strength. When we give testosterone to healthy men with testosterone deficiency, we see an increase in lean body mass and muscle mass.

Now when we look at heart failure patients, we find that up to 26-37% of patients have testosterone deficiency. Low testosterone levels are associated with increased systemic vascular resistance (this means it is even harder for the heart to pump blood to the vital organs) and reduced heart rate variability. In addition, testosterone is recognised to have ant-inflammatory properties and therefore patients with low testosterone may have higher levels of inflammation. Clinically patients who have heart failure and are deficient in testosterone will have more muscle wasting, reduced exercise capacity and worse quality of life.
When testosterone is given intravenously , we see that the systemic vascular resistance decreases and the output of the heart improves. When testosterone is given over a period of time, we see that inflammation as measured by inflammatory blood markers (TNF alpha and interleukin 1-beta) is seen to fall.

There have been a few studies looking at testosterone replacement in men with heart failure and although the studies are very small, the results are certainly very interesting.

There was meta-analysis in the journal of American College of Cardiology in 2016 which looked at all the studies regarding had been done until then and concluded that replacement with transdermal or intramuscular testosterone resulted in a significant improvement in exercise capacity. 6 minute walk test distances increased by 54meters, incremental shuttle walk tests increased by 46.7 meters. These improvements were comparable to some of the most effective licenced medications for heart failure. In addition, quality of life markedly improved in 35% of patients in TRT group.
More importantly there was no increase in adverse event in the TRT group compared to placebo.
One of the very important observations to mention is that the benefits of testosterone supplementation in heart failure may not just be limited to male patients.There was an interesting small study published in the journal of the American college of cardiology which showed that testosterone supplementation in women also improved functional capacity and muscle strength in women with advanced heart failure.

Whilst these are promising data, unfortunately not many people look for or treat testosterone deficiency in patients with heart failure and this is because most doctors tend to be protocol-centred rather than patient-centered and at present checking for testosterone levels routinely and treating testosterone deficiency has not made it into protocols. We will need bigger studies to understand the benefits and cost-effectiveness of testosterone replacement before our learned ‘experts’ who author these protocols will decide to change the status quo.