Testosterone therapy in diabetes and pre-diabetes.

Patients with impaired fasting glucose had significantly lower total testosterone levels compared to controls.

• Impaired fasting glucose was associated with a 3 nmol/L lower level of total testosterone when compared to controls.
• Data were derived from a meta-analytic approach using a systematic analysis focused on the relationship between testosterone and pre-diabetes condition.
• Clinical data from a consecutive series of 4682 patients seeking medical care for sexual dysfunction at the University of Florence were also considered.

Impaired fasting glucose was associated with a significantly increased risk of hypogonadism compared to subjects with normal glucose levels.

• Impaired fasting glucose was associated with a 1.8-fold increased risk of hypogonadism when compared to subjects with normal glucose levels.
• Secondary hypogonadism was two times higher in subjects with impaired fasting glucose when compared to rates observed in the general population.
• These findings were derived from a comprehensive systematic review with meta-analytic data where available.

Waist circumference and body mass index were identified as the best predictors of reduced total testosterone levels.

• Among the variables examined, waist circumference and body mass index resulted as being the best predictors of reduced total testosterone levels.
• This finding suggests that adiposity-related measures are more strongly linked to testosterone reduction than glycemic status alone.

Testosterone replacement therapy improved body composition, insulin resistance, and glucose profile in men with impaired fasting glucose and type 2 diabetes mellitus.

• Testosterone replacement therapy was able to improve body composition, insulin resistance, and glucose profile both in impaired fasting glucose and type 2 diabetes mellitus.
• The role of testosterone replacement therapy on body weight, lipid profile, and sexual function was described as 'less evident.'
• These conclusions were based on meta-analytic data from the comprehensive systematic review.

Weight loss and physical activity improved both metabolic profile and testosterone levels.

• Weight loss and physical activities are able to improve both metabolic profile and testosterone levels.
• A combined approach of testosterone replacement therapy and lifestyle modifications was suggested in symptomatic hypogonadal men.
• The rationale for combination therapy was to better motivate patients to perform physical activity, which can eventually result in weight loss as well as metabolic profile and sexual function improvement.

Whether testosterone replacement therapy or lifestyle modifications can prevent progression from pre-diabetes to type 2 diabetes mellitus remains uncertain.

• The authors stated that 'whether or not these approaches can prevent the development of type 2 diabetes mellitus from pre-clinical conditions requires more studies.'
• This conclusion was based on the current body of evidence reviewed in the comprehensive systematic review.