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Aromatase Inhibitors – No More, No Less

Introduction

The modern medical model is broken.  It’s curative rather than preventative, it’s under the influence and control of the big pharmaceutical companies that have a significant investment in maintaining the status quo.  A progressive healthcare system would appreciate that the cornerstones of health are lifestyle, nutrition and exercise, and that most diseases are man-made.  We tend to forget that we are made in nature, not a factory.  We are a very peculiar species, our intellect is as much a curse as it is a blessing.  Most other species live in perfect harmony with their environment, humans on the other hand seem determined to work against nature, not with it.  The lure of the destination is great, the journey is merely an inconvenience.  We follow the path of least resistance and yearn for definitive answers to questions that have no absolutes.  There are no straight lines or absolutes in nature because there is a fluidity and majestic complexity that enables harmony.  A harmony that we seem determined to disrupt and attempt to manipulate to our advantage.  We are foolish.

A progressive healthcare model would first look to lifestyle, nutrition and exercise, then hormonal health, then modern medicine.  I’m not talking about rejecting modern medicine, I’m talking about using modern medicine as the adjuvant and applying common sense to health.  The premise behind Testosterone Replacement Therapy is helping facilitate your body in achieving homeostasis and optimal function, no more, no less.  I’m tired of saying it and Lydia is even more tired of me saying it, but damn, some of you just aren’t listening!  I’ll continue to say it ’til the message is ingrained in even the most ignorant and stubborn of minds.  A good scientist appreciates the fluidity of nature and a progressive clinician understands that they are treating the individual in front of them, providing a personalised, holistic approach that is necessary to work in your patient’s best interests.  They need to appreciate that physiology changes or adapts, and that there are no constants or absolutes.

 

“Science is not the affirmation of a set of beliefs, but a process of inquiry aimed at building a testable body of knowledge constantly open to rejection or confirmation. In science, knowledge is fluid and certainty fleeting.  That is at the heart of its limitations. It is also its greatest strength.”  —  Michael Shermer.

 

If you apply a puritanical approach to TRT, it should only consist of Testosterone and Human Chorionic Gonadotrophin (HCG).  Testosterone to replace the testosterone and HCG to replace the Lutenising Hormone.  It’s common sense.  I have discussed the importance of a personalised approach to TRT in previous blogs.  I have been applying this principle and ideology since day one and have tried to instil the same philosophy in my guys so that they appreciate that I am always working with their best interests at heart.

 

The Aromatase Enzyme

Testosterone is the precursor to the bioavailable androgens – free testosterone, oestradiol and dihydrotestosterone.  Testosterone is converted to oestrogen by the aromatase enzyme that is produced by the liver.  It is predominantly expressed in the adipose tissue, skin and brain.  The aromatase enzyme converts the enone ring on the testosterone molecule to a phenol ring, thereby producing oestrogen.  Oestrogen is important for several reasons – cardiovascular health, bone strength, libido and mood to name just a few.  Whilst the absolute number is relevant, it appears that the ratio of oestrogen to the other bioavailable androgens is just as important.  For example, it is understood that the risk of prostate cancer increases with the relative increase in oestrogen to the decrease in testosterone that primarily occurs with age.  It’s not the quantitative number that’s important, it’s the ratio.  I’ve spoken before about the complexities and intricacies of homeostasis and the need to appreciate the importance of cause and effect.

 

Gold Standard Care is Testosterone & HCG

‘You shouldn’t need to add an aromatase inhibitor to your protocol to achieve stable, healthy, optimised androgen levels if you carefully titrate the dose and frequency of your testosterone and HCG injections’.  This is a principle that we should all aspire to uphold.

The reality is, some guys need an aromatase inhibitor to achieve hormonal balance.  Emphasis on some.  The decision to prescribe an aromatase inhibitor should be based on actual need, not lazy clinical practice.  It should be viewed as a temporary solution to the problem of excess oestrogen, not an integral component of gold standard TRT.  If you “Think of your male testosterone therapy as a 3-legged stool.  A missing leg causes the stool to fall over.”, then you will never achieve true optimisation.

I’ve spoken about How to Control Oestrogen before, there are numerous human and environmental factors that can increase your propensity for aromatisation.  The dangers of exposure to plastics and environmental pollutants are almost impossible to avoid, they are becoming more and more obvious as the world slowly wakes up to the devastation they are causing on our being and the planet we live on.

Health is always a work in progress and we should all strive to optimise every aspect of it.  If you can identify an area that needs improvement, address it.  It’s not about setting unrealistic goals, it’s about setting achievable goals.  If losing 10kg or packing up the booze will mean that you can stop your aromatase inhibitor, then you owe it to yourself to achieve that goal.  Less is more.

 

Aromatase Inhibitors

Aromatase inhibitors are a class of medication that prevent conversion of testosterone to oestradiol.  Historically, aromatase inhibitors have been over-prescribed by ignorant, lazy clinicians who have either subscribed to the ‘more is better’ philosophy, or have falsely believed that you don’t need to carefully titrate your dose according to the response that testosterone and HCG have on your physiology.  It’s rather tiresome arguing with these fools, but suffice to say, we have a growing movement that appreciate the importance of personalised care and the need to adopt a logical approach to TRT to reach true optimisation.

If I need to use an aromatase inhibitor, I use Exemestane.  It is a steroidal ‘suicidal’ inhibitor, meaning it inactivates the aromatase enzyme produced by the liver by binding to it so that it cannot exert its effect on the receptor.  It has a short half-life which means that you can effectively titrate the dose according to effect, thereby minimising the risk and negative effects of low oestrogen from too aggressive a dose.

The other commonly prescribed aromatase inhibitor is Anastrozole, which competitively bids for the aromatase cell receptor.  This mechanism of action means cessation can theoretically cause an oestrogen rebound.  One of the other issues with Anastrozole is that it has a longer half-life than Exemestane.  If oestrogen levels fall too low, it takes longer for the drug to be excreted.  It’s difficult to predict how a patient will respond to a fixed dose of Anastrozole, so if the dose hasn’t been carefully titrated, you run the risk of crashing your oestrogen.  It’s not that it’s an ineffective method of reducing oestrogen, but much like the longer acting testosterone esters, its effects are hard to manage due to its pharmacodynamics and longer, more unpredictable washout periods.

Symptoms of low oestrogen include:

  • Bone / joint pain
  • Fatigue / lethargy
  • Erectile dysfunction / low libido
  • Anxiety / depression / mood disturbance
  • Water retention
  • Increase fat distribution

Unfortunately, there is no effective method of raising oestrogen apart from increasing your testosterone level.  A fixed, one-size-fits-all approach to excess oestradiol, yet again, shows a basic lack of understanding of how to effectively manage your patient.  You need an individualised approach to TRT, not a sledgehammer approach.

 

“You can fool all the people some of the time, and some of the people all the time, but you cannot fool all the people all the time.” – Abraham Lincoln

 

Before you jump on the bandwagon of “NO ONE needs an AI” or “EVERYONE needs an AI”, just take a moment to appreciate that a good scientist tries not to talk in absolutes or make closed statements.  A good clinician should always question current practice and be open to new information to see if they can improve the service that they offer you.  We pride ourselves in offering personalised care that is specifically tailored to meet your individual needs and requirements.

 

Dr Robert Stevens MBChB MRCGP Dip.FIPT