Sustained weight loss with testosterone therapy in obese men with hypogonadism

Long-term testosterone therapy in obese men with hypogonadism led to sustained weight loss and improvements in multiple anthropometric parameters, according to an observational study presented at ENDO 2019.

“Our study found long-term testosterone therapy in men with hypogonadism and obesity resulted in significant improvement in measures of body size and composition,” said study lead author Dr Karim Haider from a private urology practice in Bremerhaven, Germany.

Haider and colleagues assessed data of 805 men who presented with hypogonadism at a single urological practice, of whom 57.4 percent (n=462) were obese. A total of 273 men received testosterone undecanoate injections (1,000 mg every 12 weeks; mean age 59.8 years), while the remaining 189 who chose not to receive the injections formed the control group (mean age, 63.5 years). Men who received testosterone and those in the control group were followed up for a mean 8 and 7.5 years, respectively, with a total observation time of 3,588 patient-years. Adherence to testosterone therapy was 100 percent.

Over the 10-year study, men who received testosterone experienced a progressive decrease in weight of 22.9 kg, while those in the control group gained 3.2 kg, with an estimated adjusted* difference of 26.1 kg between groups (p<0.001). [ENDO 2019, abstract MON-091]

This was equivalent to a 20.3 percent weight loss from baseline among testosterone recipients compared with a 3.9 percent weight gain among men in the control group (between-group difference, 24.3 percent; p<0.0001).

Men who received testosterone also experienced a reduction in waist circumference (-12.5 cm), while waist circumference of those in the control group increased by 4.6 cm (between-group difference, 17.1 cm; p<0.0001). BMI also decreased in testosterone recipients and increased in controls (-7.3 and +0.9 kg/m², respectively, between-group difference, 8.2 kg/m²; p<0.0001), as did waist-to-height ratio (-0.07 vs +0.03, between-group difference, 0.1; p<0.0001).

There were fewer deaths among testosterone recipients compared with the control group (n=12 vs 57; 4.4 percent vs 30.2 percent). Forty-seven myocardial infarctions and 44 strokes occurred in the control group.

“Men with hypogonadism and obesity receiving long-term testosterone therapy achieved progressive and sustained weight loss, while untreated controls gained [weight]. In addition, testosterone therapy was associated with a reduced risk of death, heart attack, and stroke,” said Haider, who suggested that the reductions in weight and waist circumference among testosterone recipients may have played a role in the reduced incidence of cardiovascular events and mortality.

“[T]estosterone levels should be measured in men with obesity, and testosterone therapy … offered if indicated,” he added.