The chance of men developing erectile function disorders increases as they get older. Diabetes mellitus can increase the risk of erectile dysfunction further. In a study of 351 men who had recently received a diagnosis of diabetes mellitus, scientists from the German Diabetes Center (DDZ) in Düsseldorf found that erectile dysfunction also occurs in men who have just developed diabetes and that the prevalence of erectile dysfunction varies between the diabetes subtypes. Medscape spoke with the study author, Haifa Maalmi, MD, research associate at DDZ, about the results of the study and what they mean for clinical practice.
Medscape: Erectile dysfunction commonly affects older men who have suffered from diabetes for many years, whose blood sugar is poorly managed, or who have additional conditions, such as high blood pressure or high cholesterol levels. However, diabetes was newly diagnosed in the men in your study. Is the high proportion of erectile dysfunction surprising, considering the short duration of the disease? And do the results mean that the onset of erectile dysfunction is independent of how long someone suffers from diabetes?
Maalmi: The relatively high prevalence (23%) of erectile dysfunction in men within a year of their diabetes diagnosis that was observed in our study did not surprise us.
Firstly, a diabetic metabolism is often present months or years before the actual diagnosis; and although the German diabetes study includes people with a known diabetes duration of less than a year, the exact diabetes duration is unknown.
Secondly, most diabetes complications (including erectile dysfunction) develop during the prediabetic stage, when hyperglycemia is above the normal value but still below the diabetes threshold value. Early damage to the arteries in the penis may have even developed during the prediabetes phase and led to erectile dysfunction shortly after the diagnosis.
Thirdly, the erectile dysfunction prevalence determined in our study corresponded to the prevalence determined in earlier studies with men in whom diabetes had only recently developed (20% to 37%).
In this context, it should also be noted that the erectile dysfunction prevalence in newly diagnosed diabetes, as in our study, is much lower than in men with a longer diabetes duration (prevalence between 35% and 90%). However, if you consider that our study subjects are relatively young (average age, 49 years), a prevalence of 23% can still be seen as high.
Medscape: Men between the ages of 18 and 69 years were included in the study. Were there age-related differences in the severity of the erectile dysfunction? That is, were older men affected more frequently, and if so, was the erectile dysfunction more severe?
Maalmi: Yes, there was a correlation between age and a worse erectility (recognizable through lower values in the International Index of Erection Function). This correlation is known and was confirmed in our study.
Medscape: What do you think: is the extent of erectile dysfunction with type 2 diabetes generally underestimated?
Maalmi: We believe that erectile dysfunction in men with type 2 diabetes and type 1 diabetes is rather underestimated. In clinical practice, the subject of sexual performance can be perceived to be too personal and sensitive. Therefore, many men (particularly older men who are not very sexually active) do not go to the doctor and remain undetected.
In epidemiological studies in which erectile dysfunction is determined using a questionnaire, most men feel that their sexual performance is a very intimate subject and prefer not to answer some questions. Consequently, the erectile dysfunction status cannot be determined in subjects with incomplete information regarding their erectile function.
Medscape: Science is increasingly united around the fact that there is not just type 1 and type 2 diabetes but rather the following five subtypes:
- Severe autoimmune diabetes, corresponding to the classic type 1 diabetes
- Severe insulin-deficient diabetes (SIDD)
- Severe insulin-resistant diabetes (SIRD)
- Mild obesity-related diabetes
- Mild age-related diabetes
Do these five subtypes now play a role in medical practice?
Maalmi: The five subtypes are fairly new (the first publication of them is from 2019) and were only used for scientific purposes. To date, it is still too early to use the diabetes subtypes in clinical practice.
One reason for this is that the clustering algorithm is very sophisticated. Another reason is that C-peptide (which is used to calculate HOMA2-B and HOMA2-IR, two variables required for the clustering) is not a routine measurement.
Even more important is that we still do not have sufficient evidence for whether therapy tailored to the individual diabetes subgroups would actually be beneficial, compared with the current guidelines. The subgroup-specific approach to treatment must be investigated in randomized, controlled studies.
Medscape: One conclusion from the study is that patients with SIRD and SIDD should be investigated specifically for erectile dysfunction. In terms of clinical practice, does this mean that the physician should pose targeted questions to the diabetes patients about erectile problems?
Maalmi: Yes. Because although we are yet not able to use this new diabetes classification in clinical practice, men with a form of diabetes that is characterized by obesity and insulin resistance and who demonstrate high fasting insulin levels (similar to subjects in the SIRD subgroup) and diabetics with severe insulin deficiency (similar to subjects in the SIDD subgroup) should be asked explicitly about their erectile function.
Medscape: Thank you very much for the discussion.