Testosterone & Hypogonadism

Sitting down with Dr Channa Jayasena


Joe McLean, BSc, MRes
March 17, 2024

Dr Channa Jayasena is an internationally recognised specialist in the field of reproductive endocrinology and leads a research group at Imperial College that aims to develop new treatments for men and women with reproductive disorders.  

A particular area of focus for Dr Jayasena is the study of hypogonadism and testosterone, and Joe McLean, the Scientific Editor for TRTed, sat down with Dr Jayasena to discuss his work and thoughts on testosterone and hypogonadism.  

For those who aren’t familiar with you or your work, can you please introduce yourself?  

My name is Channa Jayasena, I’m an endocrinologist based at Imperial College London. I do two things – half the week I treat patients with reproductive disorders such as hypogonadism and the other half of the week I run a research group to try and develop new treatments to help patients everywhere who are affected by these conditions.  

What made you interested in studying endocrinology?  

Pure accident actually! I started in general endocrine training and my research happened to be in something called kisspeptin, which is a regulator in the brain, a peptide which is needed for puberty, and one thing led to another and I discovered that men’s health, things like testosterone, are relatively under prioritised compared to how patients view them. So, I thought that would be a growth area and something worth focusing on.  

Testosterone is a relatively well-known hormone in the general population, but is it a well-understood hormone?  

It’s deeply associated with masculinity and therefore perhaps aggression. It’s really interesting that almost the reverse is true in that people who take testosterone can often feel calmer and more optimistic, and conversely, if you have very low testosterone, you can feel very anxious and low in mood. But it also has other bodily functions such as helping bone marrow make enough red blood cells so you’re not anaemic, and helping the bones stay healthy, otherwise, you can get things like osteoporosis if testosterone is too low.  

A condition characterised by low levels of testosterone is hypogonadism. Can you tell us what hypogonadism is and what are the symptoms?

It’s a state of not having enough testosterone to live healthily. It’s a combination of symptoms and blood tests revealing low testosterone levels that will be sufficient to make the diagnosis.  

Some of the symptoms are very non-specific so a man can be tired or feeling a bit low, but more specific symptoms are things like losing the ability to have erections, particularly first thing in the morning, or having low libido. Then, of course, some men may have problems such as loss of body hair on the face or armpits, feeling weaker, or getting anaemic (having low levels of red blood cells) so they may also feel a bit breathless when walking around. And in extreme cases, they may have a fracture after a fall because their bones have become thin.  

What causes hypogonadism?

I’ll highlight three causes; one is the form we’ve been talking about and some might call it functional hypogonadism – it has so many terms – some call it late onset some call it functional – and this is a really deteriorating health-related low testosterone. The other one is called classic primary hypogonadism which I also talked about before which is where young men might lose a testis because of cancer or because they have a condition such as Klinefelter syndrome. And the third one is uncommon but very important to spot properly because it affects their management – and that is secondary hypogonadism where the pituitary or the hypothalamus which are needed to make the testes work, don’t work. That can either happen during birth in which case you won’t go through puberty, we call that congenital or it can be acquired after puberty such as a pituitary tumour or head trauma, these three are all treated with testosterone but there are differences in the way that other treatments would be planned.  

So differentiating between the cause of hypogonadism is important?

We mentioned this in our society for Endocrinology Guidelines – it’s critical. Saying someone is hypogonadal is not enough, you really want to pinpoint what caused it so you can then properly manage your patients.  

In the diagnosis of hypogonadism, does a patient need to have clinical symptoms of hypogonadism as well as a blood test confirming low testosterone?  

There have been many efforts to find a binary one-size fits all test that can magically tell you ‘’right, I have hypogonadism’’. Unfortunately, that’s never been possible and there’s significant overlap and you need to put the results in the context of your patients. Clinical clues and specific symptoms are equally important.  

Ultimately there is a case by case but there are also strong indicators, for example, let’s say someone has not gone through puberty and has very small testis, then of course the dice are loaded very much in favour of interpreting low testosterone levels being highly likely to be consistent with hypogonadism. But then there are other symptoms which may push you into thinking we’re confusing hypogonadism with another condition, so it’s all about corroborating the blood tests with a clinical history.  

Should we consider hypogonadism a serious condition? Does it negatively impact the quality of life in an affected patient?

It does indeed. So we know it negatively impacts quality of life, it obviously causes severe sexual dysfunction, it can cause anaemia, osteoporosis and some degree of muscle wasting – it’s certainly something not to take likely if it’s diagnosed approximately.  

A widely debated topic is the role of ageing on testosterone levels. Does ageing independently cause a decline in testosterone levels?

I have many healthy discussions and debates with colleagues of mine. My take on it is, that we know from a large-scale population study called the European Male Ageing Study that testosterone does indeed decline with age in a small amount around 1% a year. Factors that encourage or increase that decline are factors such as general health, how many medications you are on, how obese you are, and whether you have diabetes. So, it’s the combination that can overlay to make the condition right for hypogonadism. But, just being old per se is not enough to be hypogonadal.  

With diseases such as diabetes and obesity rising, should we expect to see a concomitant increase in hypogonadism?

I expect so. And I think it’s really important to take a holistic view in these patients. In general, hypogonadism particularly for older and middle-aged men is a sign of not being well and not being fit, so we need to take a multifaceted approach. Testosterone is one answer in terms of treatment, but other things such as lifestyle intervention and weight loss are, some would argue, more important.  

For patients with obesity (or other reversible comorbidities) who also have hypogonadism, is lifestyle intervention the first step in treatment or should they be prescribed testosterone?  

There are lots of different guidelines, ours and the American guidelines would say in such a scenario that we should really be encouraging patients to do lifestyle intervention. However, we live in a society where we know it is very difficult. And we wouldn’t need bariatric services and weight loss services if it was easy for people to do that. So I also take a pragmatic approach, and I say that let’s say someone has a BMI of 40 and they have no immediate hope of losing weight sufficiently but they have tried then I am okay with giving them testosterone as long as we don’t lose sight of the fact of what would be ideal and cannot be given – so I’m a pragmatist, we have to help our patient as well and we can’t be purists and say ‘’you’re still obese, well we’re just not going to treat you and you should suffer’’.  

For patients with hypogonadism, what is the treatment goal? What should patients expect to see after the initiation of treatment?  

I teach other colleagues about this in meetings and conferences - don’t forget to ask patients how they feel. The number one thing is they should be symptomatically better; the most obvious endpoint is sexual function, things like erections, libido, and also mood and their general quality of life. So they should be feeling better and if you have got someone who isn’t, then you really got to think are they on the right dose? And that’s why we check blood levels and see whether they’ve had adequate exposure, but we also question diagnosis as well. We also for example in the longer term might look at things like bone density if they have osteoporosis and if they’re anaemic then we’ll look at their hematocrit to check that their blood cell count is going up.  

What treatments are available for hypogonadal patients?  

Testosterone can be broadly given as a gel, and there are various preparations for that – it can also be given as injections and there are longer-acting and shorter-acting injections available.  

In modern society, we see people looking up their symptoms online and receiving their google diagnosis. Some patients may even self-medicate with testosterone supplements. Is this safe?

I am really glad that you brought this up. We think that this is a worrying and growing trend, particularly amongst younger men, and often the reasons are wanting to improve one's body image and maybe feeling low. The problem with taking these supplements and taking them non-medically is, first of all, there are no benefits to your health and in fact, they are harmful to your health. Everything I said before about not having an association with heart problems is not true if you’re taking it and you don’t need it. If you’re taking it too much it’s undoubtedly going to cause problems with blood clots, maybe increase blood pressure and cause strokes – so it’s not safe. Secondly, when you take supplements particularly online outside of traditional prescribing behaviour, you may be taking preparations that are pure and also are completely the wrong dose. So I would urge people to always seek medical care and get a proper diagnosis. 

In terms of future research, what would you like to know?

I think tailoring treatment is always good, and I think trying to find for different subgroups; the young men who may have lost a testicle, the men with hypothalamic-pituitary problems, the men with obesity, etc., how to tailor treatment for these men, how much testosterone they need? What levels of testosterone in their bloodstream should we be achieving? And trying to do more about what the benefits are and how we can better predict the benefits so that we can hopefully translate to better practice, which we call personalized medicine.  

If there’s one key message you would like to get out to the public about testosterone, what would it be?  

I would say, that for most people in the public, for most men, getting hypogonadism is not an inevitability, the best thing you can do is to stay in good shape, watch weight, watch what you’re eating and exercise healthily – the best means of treatment is prevention. That’s the best thing I can say.  

We have one question from a member of the general public! ''A lot of young people in bodybuilding are using testosterone products to enhance their performance and physique, is it safe?''  

What we call proverbially, steroids, are really unsafe. They can cause long-term infertility, they actually can cause psychosis, psychiatric disease and normal men to be violent and actually get put into prison, and can cause awful withdrawal symptoms including suicide, so please please please, absolutely not!  

Thank you to Dr Channa Jayasena for joining us here at TRTed! We hope you found this interview helpful, and keep an eye-out for more featured interviews with leading experts in men's health.

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