Table 2

Prevalence of Hypogonadism in Men with Erectile Dysfunction (serum total testosterone).

The prevalence of hypogonadism ranged from 1.72 to 47.7 percent. In one study conducted in Japan, hypogonadism was found in 47.7 percent of the patients. Note that all participants in this study had been diagnosed with partial androgen deficiency of the aging male (PADAM) before entry in the study.⁶⁸ In one study, ³⁸ which reported a prevalence of 6.6 percent, patients had been receiving androgen therapy. In Zohdy et al. 2007⁷⁵ all participants presented with obesity and other signs of metabolic syndrome.

In several studies, patients with ED and hypogonadism, who had been referred to urology clinics, were found more likely to have decreased libido, ^{20, 38, 67, 72} testicular damage/abnormality, ^{20, 38, 70} psychological problems with their partner, ⁷⁰ arterial disease, ^{70, 72} obesity, ^{67, 75} hyperlipidemia, ⁶² diabetes, ^{62, 72} or hyperprolactinemia.⁷²

In other studies, patients with hypogonadism did not differ (p-value > 0.05) from eugonadal patients either with respect to age, ^{60, 64, 67} ED severity, ^{60, 62, 67} ED duration, ^{60, 67} the presence of chronic disease, ⁶⁰ smoking, ⁶⁰ loss of libido, ⁶⁴ or premature ejaculation.⁶⁷ In contrast, one study⁷² demonstrated that age, ED severity, and longer duration of ED were statistically significant predictors of having hypogonadism in patients with ED.

In two primary care clinic based studies, ^{57, 65} hypogonadal patients were more likely to have higher levels of prolactin⁶⁵ or hypothalamic abnormalities than those with normal levels of testosterone (21.2 versus 2.9 percent).⁵⁷

Prevalence of Hypogonadism (Free Serum Testosterone Levels)

Two studies reported the prevalence of hypogonadism measured by FT (radioimmunoassay, analog method)^{66, 74} and two studies reported calculated FT levels based on the TT serum levels (Table 3).^{59, 73}