Testosterone therapy in classical vs. functional hypogonadism - INTERVIEW
We have been using intramuscular testosterone undecanoate for treatment of hypogonadism in Munster for more than 20 years. We started using it in 1997 and have very good experiences with this kind of treatment. Our patients are satisfied with the treatment concerning relief of symptoms. Those who are obese and/or have type 2 diabetes also see a marked weight loss and improvement in metabolic parameters.
We see several types of patients with hypogonadism. We have those with classical forms of testosterone deficiency, which could be primary hypogonadism – that means originating from the testes - or secondary hypogonadism that originates in the pituitary or hypothalamus area. And of course, we see men with so-called late onset, or functional hypogonadism. That means it comes later in life and is usually related to a chronic disease. It could be an inflammatory disease, but mostly it is obesity or type 2 diabetes.
We do not see differences in the effects of testosterone treatment between the classical and functional forms of hypogonadism. The exception is obese men with functional hypogonadism who start testosterone therapy with a higher weight (they are also usually older), so the effects may be even stronger in these patients because they have more weight (body fat) to lose.
Testosterone treatment improves body composition by causing loss of fat mass and increase in muscle (lean) mass. This has important metabolic implications. The increase in muscle mass is particularly important as it is associated with increased insulin-sensitivity in men who have type 2 diabetes. We are currently working on a long-term trial investigating the effects of testosterone therapy on fat loss, muscle gain and metabolic effects.
I think regarding adherence to testosterone therapy, I have the experience that patients really stick to it because they feel and see the benefits, such as improvements in sexual symptoms and mood, and later, weight loss. Doctors who treat hypogonadal men with injectable testosterone undecanoate have more control over the treatment as patients have to come back every three months to get their injection. Compliance is less clear with self-applied preparations, such as gels that need to be rubbed onto the skin daily by the patient.
When would I recommend measuring testosterone? I think you should measure testosterone if the patients come to you with symptoms. They wouldn’t come if they don’t have symptoms. Usually these symptoms are of sexual nature, or they have depressive mood or lack of vigor. I also think that obesity or type 2 diabetes are symptoms, or at least signs of hypogonadism. This has been acknowledged by the American Association of Clinical Endocrinologists; in their guidelines they state that patients who are obese or have type 2 diabetes should be screened for hypogonadism, because it is so frequent in these people.
Prof. Dr. med. Marija Pfeifer Medical Faculty University of Ljubljana, Slovenia
Prof. Dr. Michael Zitzmann
Andrologist, Endocrinologist, Diabetologist Sexual Medicine (FECSM) Clinical Andrology / Centre for Reproductive Medicine and Andrology, University Clinics Muenster Germany