Current retrospective analysis of real-life data from a cohort of consecutive white-European heterosexual sexually-active men at a single outpatient centre over the last 11 years depicted that one out of three patients (30.8%) seeking first medical help for new-onset ED as their primary and only self-complaint also suffered from concomitant uLSD/I. Patients with ED and uLSD/I were older, had more comorbid conditions, showed a worse hormonal profile and had more severe ED than those with only ED. As such, lower levels of tT, lower IIEF-EF scores and BDI scores ≥ 11 at baseline emerged to be independently associated with uLSD/I in men self-presenting for ED only. As a whole, these observations emerged to be clinically relevant since they should lead to a significant rethinking of any tailored management work-up of ED patients, especially of those who could conceal other concomitant SDs (thus making patient management significantly more complex in the everyday clinical practice). This emerges to be of particular importance since the combination of embarrassment also linked to desire makes men even more fragile, with different expectations and probably less prone to follow physicians’ suggestions (29, 30).
The prevalence of ED in the general population has been largely explored in several studies with a steep age-related increase from 2.3–53.4% (3). Conversely, only few data exist concerning the actual prevalence of a broader concept and even more delicate concept such as LSD/I in men. Meissner et al. reported a 4.7% prevalence of LSD/I in the general population by using an online survey directed to 12,646 German middle-aged men (31). Similarly, an Italian cross-sectional study with data from 2,013 at a single tertiary academic centre reported a prevalence of LSD/I of approximately 10% (4). Moreover, previous studies showed that the coexistence of ED and LSD/I varies between 4 and 40% (11, 13, 32). Noteworthy, data from existing literature investigated LSD/I presence in men as self-reporting with online survey or as primary reason for office evaluation; on the contrary, we deliberately excluded men who have declared LSD/I at entrance to specifically capture uLSD/I (as defined by using IIEF-SD sub domain). In this context, our results depicted that almost 30% of men seeking first medical investigation for new onset ED had concomitant uLSD/I. Therefore, our results depicted the lack of awareness of a common disorder in patients seeking first medical help only for ED and warn sexual medicine experts to more comprehensively investigate other SD in every patient.
Older patients have higher risk of ED (33) and age is commonly used to guide treatment decision making in men with poor erectile function (29). Moreover, data from the European Male Ageing Study (EMAS), showed that aging impact directly on sexual desire (34). Furthermore, many comorbidities are listed in the pathogenic pathways of both ED and LSD/I (3, 35–37). Accordingly, Laumann et al., in the Global Study of Sexual Attitudes and Behaviours, showed that in a cohort of 13.618 men aged 40–80 years from 29 countries a decreased sexual interest was associated with older age and an overall poor health (2). Considering the impact of both age and comorbidities on the coexistence of ED and LSD/I, Salonia et al. conducted a cross-sectional study involving 790 patients and showed that severe CCI scores were independently associated with the coexistence of both self-reported ED and LSD/I (11). Conversely, Corona et al. found that in men presenting for new-onset ED, a decreased sexual desire was more frequently associated with a healthier status (32). Here we confirm that the prevalence of uLSD/I in men seeking medical for new onset ED only was higher in older men and in those with more comorbidities at the time of first investigation.
The coexistence of low sexual desire, decreased morning erections and ED has been recognized as the strongest predictor of testosterone deficiency, with circulating T being the most clinically relevant factor influencing men’s sexual desire (38, 39). Of clinical importance, current findings depicted that men with ED + uLSD/I have significantly lower values of tT than men with ED-only and lower tT values emerged to be associated with uLSD/I, although groups were comparable in terms of prevalence of T deficiency (as for tT ≤ 3 ng/mL (28)). To this regard, data from existing literature declares that in men with ED the loss of sexual interest was not associated to a defined hypogonadism status, although patients with decreased libido had lower levels of tT with respect to men complaining of ED without LSD/I (13). Furthermore, Corona et al. reported that the hormonal balance orchestrates an important role in defining sexual health, and endocrine abnormalities are common in men with the impairment of both sexual desire and erectile function (40). In this context, our results revealed that men with ED and uLSD/I had higher serum levels of TSH and FSH, even if both were within the range of normality. Noteworthy, in the consideration of the open debate on the actual importance of T/E2 ratio in determining the coexistence of both ED and LSD/I (12), our analysis did not depict any significant difference between groups.
Lastly, the loss of sexual desire could be considered as an acquired and psychological consequence of ED status (13). Decreased sexual function may have detrimental impact toward both partners quality of life (41), and men with ED are at higher risk of depressive moods (42). Our findings substantiate this previous observation; indeed, ED + uLSD/I patients had worse scores for depression than ED-only patients.
A first strength of our study is that all patients were enrolled at a same outpatient clinic thus representing a typical real-life scenario. Second, our analyses were limited to a large cohort of same-race, sexually active patients thus eliminating potential ethnic difference. Third, we have assessed only patients not self-reporting LSD/I by means of validated questionnaires (i.e., IIEF-SD domain score, with the median value as an instrument to highlight the presence of uLSD/I).
Our study is certainly not devoid of limitations. First, it is a cross-sectional retrospective analysis at a single, tertiary referral academic centre thus raising the possibility of selection biases. Second, our data may not reflect an actual change of disease incidence, defined as the number of cases observed over one year, but rather a change in the prevalence of each condition among patients seeking help for ED. Thereof, larger cohort studies across different centres and populations are needed to validate our findings. Yet, all patients have been consistently analysed over time by a single expert physician, thus limiting at least potential heterogeneity associated with differences in diagnostic work-up methodology. Third, although every patient has been comprehensively and homogeneously investigated we have arbitrarily considered the median value of the IIEF-SD domain as a valid threshold below which patients had been defined as having uLSD/I. In contrast, more adequate validated questionnaires to assess LSD/I (e.g., Male Sexual Health Questionnaire (MSHQ) (43)) are actually available. Therefore, the methodology we adopted for this specific analysis is probably not the best available in terms of psychometric tools and questionnaires, and it may only indicate to physicians the need to better investigate patients’ needs and sexual satisfaction with a more appropriate multimodal approach. However, despite this may be a major bias of the analysis, we consider that it could even be eventually considered a major strength, as IIEF-SD can be easily used in daily clinical practice, and even more useful for better tailoring the management work-up.
In conclusion, one out of three men seeking first medical help for ED only had criteria for an unreported LSD/I, according to the IIEF-SD domain score. Compared to those with normal sexual desire, men with both conditions were older, had higher rates of severe ED, more prevalent depressive symptoms, and lower serum tT levels, even if not suggestive for hypogonadism. A detailed investigation of sexual desire should be always included in the diagnostic work-up of men with ED, in order to better tailoring patient therapeutic management.