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Concept: Hypogonadism


Testosterone is essential for the regulation of erectile physiology, but the relationship between low testosterone and erectile dysfunction (ED) has not been firmly established.

Concepts: Cross-sectional study, Testosterone, Erectile dysfunction, Hypogonadism


Reduced libido is widely considered the most prominent symptomatic reflection of low testosterone (T) levels in men. Testosterone deficiency (TD) afflicts approximately 30% of men aged 40-79 years. This study seeks to evaluate the effect of a new natural compound “tradamixina "in order to improve male sexual function in elderly men, particularly libido and possible erectile dysfunction, versus administration of tadalafil 5 mg daily.

Concepts: Sociology, Testosterone, Group, Ageing, Erectile dysfunction, Hypogonadism, Sexual function, Sexual dysfunction


Aim: To determine the effect of a 12-month intent-to-treat tesosterone replacement therapy (TRT) trial on QTa interval variability (QTaVI) in hypogonadal (HG) men with spinal cord injury (SCI). Method: A prospective, controlled, 12-month TRT trial was completed in twenty-two healthy, chronic, non-ambulatory men with SCI. Based on serum T concentration, subjects were designated as HG (≤11.3 nmol/l) or eugonadal (EG, ≥11.4 nmol/l). Digital 3-lead electrocardiograms were performed. Heart rate (RR), heart rate variability [(HRV), including total power (TP(RR)), low frequency (LF(RR)) and high freguency (HF(RR))], QTa, QTe, and RT intervals, QTC (Bazett), QTVN, and QTaVI were calculated and evaluated at baseline and 12 months. Lipoprotein profiles (triglycerides, total cholesterol, low density and high-density lipoproteins) were obtained at the respective time points. Results: Based on serum T concentration, 13 subjects were designated as HG and 11 EG. During the trial, there were no group differences for RR, QTa, QTe or RT intervals, QTC, TP(RR), HF(RR), or lipoproteins. The HG was older (p < 0.05) and LF(RR) was lower (p < 0.05) at baseline. At baseline, QTaVI was significantly greater in HG compared to EG [-0.17 (0.92) vs. -1.07 (0.90); p < 0.05]. After TRT, this group difference was no longer present [-0.44 (0.87) vs. -0.65 (0.85)] and the change in HG was significant (p < 0.05). Conclusion: Hypogonadism in men with SCI was associated with elevated QTaVI at baseline. After 12 months of physiological TRT, the QTaVI improved in association with raising T into the normal range. These findings occurred independently from the prolongation of the QT interval.

Concepts: Cholesterol, Cardiology, Lipoprotein, Lipoproteins, Cardiac electrophysiology, Testosterone, QT interval, Hypogonadism


This study examines the physiological impact of a glucose load on serum testosterone (T) levels in men with varying glucose tolerance (GT).

Concepts: Osteoporosis, Testosterone, Hypogonadism


Determining the etiology of delayed puberty during initial evaluation can be challenging. Specifically, clinicians often cannot distinguish constitutional delay of growth and puberty (CDGP) from isolated hypogonadotropic hypogonadism (IHH), with definitive diagnosis of IHH awaiting lack of spontaneous puberty by age 18 yr. However, the ability to make a timely, correct diagnosis has important clinical implications.

Concepts: Evaluation methods, Testosterone, Law, Hypogonadism, Anabolic steroid, Delayed puberty


Late-onset hypogonadism (LOH) is defined as the condition caused by the decline of testosterone by aging, along with various symptoms, including physical, psychological and sexual disturbance. Thus the principle of treatment for LOH is Androgen replacement therapy (ART) , and ART has been applied primarily in order to alleviate the various symptoms in LOH patients. The indication of ART for LOH is determined based on LOH symptoms assessed by aging males' symptoms (AMS) score and serum free testosterone levels. In abroad, several routes are available for the administration of testosterone, such as injection, patch, oral administration, etc. In Japan, intramuscular injection of testosterone enanthate every 2 to 4 weeks is widely indicated for treatment of LOH. It has also reported that ART using testosterone ointment once or twice a day appeared to improve those LOH symptoms. ART is a significant and safe procedure for anti-aging in male.

Concepts: Osteoporosis, Testosterone, Androgen, Hypogonadism, Anabolic steroid, Intramuscular injection, Andropause, Androgen replacement therapy


Clomiphene citrate (CC) and anastrozole (AZ) have been used off label to increase testosterone (T) in hypogonadal infertile men (HIM). Both medications have been shown to increase T with different effects on estradiol (E2) and T-to-E2 ratios. There are no reported randomized trials comparing CC and AZ to improve T levels in HIM. We aimed to establish equivalence of CC vs. AZ with respect to improvement in T levels in HIM.

Concepts: Comparison, Improve, Testosterone, Estradiol, Comparisons, Hypogonadism, Citrates, Clomifene


There has been a recent increase in the number of Operators presenting to clinics for evaluation of possible low testosterone. In response, USASOC recently released an Androgen Deficiency Clinical Practice Guideline (CPG) to help guide providers through the initial evaluation and treatment of patients. The diagnosis of hypogonadism is based on consistent signs and symptoms of androgen deficiency and unequivocally low serum testosterone (below 300ng/dL). Testosterone levels can change for a variety of reasons and an adequate evaluation requires multiple laboratory tests over a period of time. If a diagnosis of hypogonadism is confirmed, differentiating between primary and secondary hypogonadism can help guide further care. Testosterone replacement therapy options are available, but careful monitoring for side-effects is required. Controversy still exists surrounding the safety of testosterone replacement therapy, and referral to endocrinology should strongly be considered before initiating treatment.

Concepts: Time, Osteoporosis, Medical terms, Endocrinology, Testosterone, Medical sign, Hypogonadism, Anabolic steroid


Delayed puberty (DP) in boys is the lack of sexual maturation at a chronological age of 14 years. Several conditions induce DP and they can be classified into reversible and irreversible causes. The most common cause of DP is constitutional delay of puberty (CDP; 63%), followed by DPs due to functional hypogonadotropic hypogonadism (HH; 20%), congenital isolated HH (9%) and hypergonadotropic hypogonadism (7%). A correct diagnosis, although often difficult, is pivotal for choosing the most adequate therapy. In CDP boys, expectant management can be an option. However, patient’s psychological distress can be attenuated by short-term low-dose testosterone therapy, which can induce male secondary sexual characteristics. When therapy is discontinued in CDP, pubertal development continues similarly to normal boys. Long-term testosterone therapy is the only option in boys with DP due to hypergonadotropic hypogonadism, whereas in subjects with HH, besides long-term testosterone, also gonadotropins and gonadotropin-releasing hormone (GnRH) can be used. Gonadotropins and GnRH, besides inducing secondary sexual characteristics, can also induce testicular maturation and spermatogenesis. Other molecules, such as kisspeptin and neurokinin B agonists, are now under evaluation as new therapeutic options for treating DP.

Concepts: Testosterone, Puberty, Hypogonadism, Kallmann syndrome, Anabolic steroid, Kisspeptin, Precocious puberty, Delayed puberty


Atrial fibrillation (AF) is the most common cardiac dysrhythmia associated with significant morbidity and mortality. Several small studies have reported that low serum total testosterone (TT) levels were associated with a higher incidence of AF. In contrast, it is also reported that anabolic steroid use is associated with an increase in the risk of AF. To date, no study has explored the effect of testosterone normalization on new incidence of AF after testosterone replacement therapy (TRT) in patients with low testosterone.

Concepts: Heart, Atrial fibrillation, Testosterone, Androgen, Steroid, Hypogonadism, Anabolic steroid, Anabolism