Beste apotheek van Nederland

clinics (urology, andrology, and endocrinology). 20,38,58,61,67,72 The mean age of participants
ranged from 47 to 59 years. Only five studies reported important comorbidities, such as
hypertension, diabetes mellitus, and ischemic vascular disease. Further details on these studies
are provided in Table 5.
Prevalence of Hyperprolactinemia (Serum Levels of Prolactin)
The information on prevalence of hyperprolactinemia using the total level of serum prolactin
was reported in 10 studies (Table 6). Erectile dysfunction was diagnosed using a combination of
clinical examination and a validated questionnaire (IIEF–5 was reported in only four of the 10
included studies). Information on the cut-off used to define a positive test result was provided in
all studies and ranged from 18 to 20 ng/mL. In these studies, except for one conducted in
Egypt, 72 the prevalence of hyperprolactinemia ranged from 1.42 to 14.3 percent.
The prevalence rate of hyperprolactinemia reported in the Egyptian study was 32 percent. 72
The high prevalence observed in this study is not readily explained. Study participants were
aging, obese men with ED. Of a total of 877 enrolled patients, 305 completed the study. The
mean age was 53.9 (range 26–86) years; 77 percent of the patients were older than 50 years, 86
percent were overweight or obese, and 30 percent were current or former smokers. 72
In two other studies, the prevalence rates of hyperprolactinemia were compared between men
with and without ED. 60,73 These studies used similar cut-off points to define a positive or
negative test result (Table 7). The prevalence rate of hyperprolactinemia among men with ED in
the two studies ranged from 2.89 to 9.54 percent.
Prevalence of Abnormal Levels of LH/FSH
Information on the prevalence of abnormal levels of LH/FSH in men with ED was provided
for eight studies. 20,61,63-65,67,69,73 The studies were divided according to whether they measured
secondary hypogonadism (low levels of LH and/or FSH) or primary hypogonadism (high levels
of LH and/or FSH). All studies included men with a previous diagnosis of ED. In two studies
levels of LH were measured only in patients with low levels of total testosterone. 61,63 The
diagnosis of ED was done by a combination of clinical examination and validated questionnaire
(IIEF–5 or SAQ; reported in three included studies). The cut-off values used to define a
positive/negative test result were provided for two studies only (Tables 8 and 9).
Secondary hypogonadism (low levels of LH and/or FSH). In Bunch et al. 2002, 66
patients with hypogonadism were screened for LH levels. Of these, 44 percent had low levels of
LH (<13 IU/mL) and were diagnosed with secondary hypogonadism. Further screening with
magnetic resonance imaging (MRI) or computer tomography (CT) imaging led to the
identification of hypothalamic-pituitary abnormalities in 10 percent of these men. 63
El-Sakka 2005 67 assessed the prevalence of endocrine abnormalities in obese men with
sexual dysfunction. Low levels of LH and FSH were identified only in 1.7 percent of men (Table
9).
Primary hypogonadism (high levels of LH and/or FSH). In three studies, the proportion of
men with ED who had abnormally high levels of LH ranged from 1.03 to 5.79 percent. 20,65,73
There was a prevalence of 21.7 percent in a study in which all men had been previously
diagnosed with hypogonadism (i.e., low testosterone levels). 61 Another study 69 investigated
possible hypothalamic impotence in 21 ED patients (median age 54 years) with low testosterone
and normal levels of LH or FSH by undergoing gonadotropin-releasing hormone (GnRH)
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