Diabetic men at risk of testosterone deficiency
Men with diabetes (either type 1 or 2) commonly also have hypogonadism (a condition characterised by deficiency of the male hormone testosterone), and vice versa. Male hypogonadism is associated with insulin resistance, which typically precedes type 2 diabetes, and men with hypogonadism are more likely to develop type 2 diabetes mellitus than men with sufficient testosterone levels. There is also an association between type 1 diabetes, insulin resistance and testosterone deficiency (TD).
Despite these strong associations, testosterone deficiency remains undiagnosed and untreated in many diabetic men. To improve diabetes control and general health, it is important that all diabetic men undergo screening for testosterone deficiency to enable administration of testosterone replacement therapy (TRT) if required. TRT not only restores testosterone levels in deficient men; in doing so it also optimises diabetes treatment.
Testosterone and type 2 diabetes
It has been shown that up to 42% of men with type 2 diabetes have low or borderline levels of free testosterone, and up to one third have sufficiently low testosterone levels to be classified as hypogonadal. Low testosterone levels can cause a range of symptoms in your body that can have a substantial impact on your health and happiness. These symptoms include reduced sex drive, changes to body composition, mood disturbances, and insulin resistance. Furthermore, the association between testosterone deficiency and diabetes becomes stronger as you get older. In one study, about 30% of diabetic men aged 40–49 had hypogonadism, while nearly 64% of men aged over 69 had the condition.
Research has shown that men undergoing testosterone withdrawal therapy (reducing testosterone levels, for example to treat cancers that grow quickly in the presence of testosterone) experience increasing insulin and glucose levels. The exact mechanisms by which testosterone exerts these effects are not completely understood, but it is well established that untreated insulin resistance can lead to type 2 diabetes.
Low testosterone is also associated with obesity and abdominal obesity, which is an important risk factor for insulin resistance and, in turn, the development of type 2 diabetes. Increasing deposition of fat around the abdomen results in lower levels of testosterone in the body and creates a self-perpetuating cycle of increasing fat and decreasing testosterone. Therefore, it is important to recognise and break this cycle as early as possible.
Testosterone and type 1 diabetes mellitus
Like type 2 diabetes, type 1 diabetic men are likely to have lower testosterone levels and higher insulin resistance than the general male population, and these associations become more pronounced with increasing age. In particular, insulin resistance has been shown to increase the risk of adverse health outcomes for type 1 diabetic men.
A proactive approach to screening needed
It is therefore important for all diabetic men to visit their doctor and undergo screening for testosterone deficiency to ensure that if they have hypogonadism, the condition is diagnosed and treated. However, men may find it difficult to discuss matters such as testosterone deficiency with their doctor, and there are numerous barriers which may prevent doctors from discussing this condition with diabetic men.
There is no recommendation to guide doctors in assessing the testosterone levels of diabetic men, despite screening recommendations existing for other diabetes-related conditions such as diabetic eye disorders. As a result, practitioners may not be fully aware of the importance of assessing testosterone.
According to Dr Neale Cohen, General Manager of Diabetes Services at Baker IDI, the low level of general awareness is compounded by diagnostic difficulties.
“Testosterone deficiency is not a condition that is screened for routinely unless there is symptomatic evidence of erectile or sexual dysfunction, and there is considerable controversy regarding the cut-offs used to identify cases of TD. However, often the symptoms are non-specific, such as tiredness and mood changes, and without the appropriate blood tests, mild forms of TD will go undiagnosed,” Dr Cohen said.
Time constraints may lead doctors to focus on acute complications of diabetes in a short consultation, such as regulating insulin or blood pressure. Your doctor may also lack the confidence to proactively discuss sexual matters. If they do, they may focus on the diagnosis of erectile dysfunction (ED) and its treatment with phosphodiesterase-5 (PDE-5) inhibitors due to high public and professional awareness of this condition.
If you have diabetes, you may also be embarrassed to discuss testosterone deficiency with your doctor because it involves a discussion of sexual matters. It’s possible that you haven’t even noticed that you have symptoms of this condition. Symptoms of testosterone deficiency, such as changes to your sex drive and body shape, may develop slowly since testosterone levels generally decline gradually over many years. If you have noticed changes, you may have thought they were just a normal part of ageing, rather than symptoms of a treatable condition. Dr Cohen believes that physicians need to help promote awareness in their patients.
“In particular, physicians should stress the association of TD with diabetes, obesity and metabolic syndrome,” said Dr Cohen.
Overcoming barriers to screening
If you have diabetes and are considering discussing testosterone deficiency with your doctor, bear in mind that the doctor is a health professional and will treat sexual health problems the same way as other health problems. Be specific when talking to your doctor about the symptoms you’re experiencing. For example, asking general questions such as whether or not diabetes “affects a man’s nature” may not prompt your doctor to consider sexual health issues. If raising the issue is difficult for you, completing a testosterone assessment survey and taking it with you to your next doctor’s appointment may help you to broach the subject.
Overcoming the barriers that prevent you from discussing symptoms with your doctor is important; unless you undergo screening for hypogonadism, the condition cannot be diagnosed and treated. However, these is also some debate about what level of TD should be eligible for TRT.Testosterone replacement improves markers of diabetes
“TRT is approved for treatment of testosterone deficiency in Australia and available on the PBS, but only in quite significant cases where the testosterone levels of the patient are below 8.0 nmol/L. There is ongoing debate regarding how to set this cut-off,” said Dr Cohen.
Treatment is necessary not only to restore your testosterone levels, but also to ensure your diabetes treatment is optimally effective.
Historically, there has been reluctance amongst doctors to use TRT in diabetic men for fear of inducing adverse cardiovascular events like heart attacks. However, studies have now shown that TRT is not associated with increased cardiovascular risk in diabetics. On the contrary, there is considerable evidence that TRT for diabetic men has numerous health benefits. This position is supported by Dr Cohen, although he suggests more research is needed in some areas.
“There is considerable evidence showing that TRT can have benefits for lean body mass, fat mass, bone density, insulin resistance and general wellbeing/psychosocial effects. However, there is still quite a bit of controversy regarding the benefits for cardiovascular health and blood glucose control. Further studies are needed in these areas,” Dr Cohen said.
Treating hypogonadism is important in its own right and has been associated with improved sexual function, body composition and quality of life. In diabetic men it also optimises the effect of diabetes treatment. Studies examining the effect of TRT on markers of diabetes have reported the following benefits compared to other diabetes treatments:
- Reduced waist circumference/abdominal obesity;
- Improve waist–hip ratio (a measure of obesity);
- Improved insulin and glucose levels;
- Improved cholesterol levels;
- Reduced body mass;
- Reduced body weight; and
- Reduced body mass index (BMI).
Evidence that cannot be ignored
Evidence supporting the use of TRT in testosterone deficient men is compelling. As type 2 diabetes mellitus is now highly prevalent in Australia and other developed countries, improving diabetes treatment is of increasing public health importance. TRT restores testosterone levels in diabetic men without increasing the risk of cardiovascular events. Furthermore, treating testosterone deficiency is important in its own right and can improve quality of life through correcting low libido and erectile dysfunction, improving body composition, and alleviating testosterone deficiency-related mood disorders.
If you have diabetes and symptoms of testosterone deficiency, be proactive about discussing these symptoms with your doctor and don’t be reluctant to ask to be screened for hypogonadism. This will ensure your testosterone deficiency is diagnose and treated, which will to improve your diabetes control and general health.
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