鶹ý

Testosterone Tied to Sustained Weight Loss in Men With Hypogonadism and Obesity

— Small data set finds large weight reductions over time

MedpageToday

SAN DIEGO -- Long-term testosterone therapy was associated with sustained reductions in weight for men with hypogonadism and class III obesity, a researcher reported.

In registry data on 76 patients, those who opted to receive testosterone undecanoate experienced a 26% reduction in their body mass index (BMI) over close to a decade of follow-up, reported Farid Saad, DVM, PhD, of Bayer AG in Berlin and Gulf Medical University in the United Arab Emirates.

Mean BMI among the 62 patients who underwent the three injections per month fell from 41.9 to 31.1 over the study period (P<0.0001), he said here at the annual Obesity Week meeting.

In contrast, a control group involving the 14 patients who declined the injections had a non-significant mean BMI decrease of 43.0 to 41.7. Weight decreased by an average 34.6 kg (76.3 lb) in the testosterone group and 11.2 kg (24.7 lb) among controls.

The findings add evidence to the theory that testosterone supplementation can help certain men shed pounds.

"We found men losing weight after analyzing 4-year data, and we keep investigating whether men, at some point, regain weight," said Saad. "So far, this has not happened."

All-cause mortality was significantly lower in the testosterone group as well (9.7% vs 64.3% among the small control group).

Three in four men with class III obesity -- defined by a BMI of 40 or higher -- have testosterone deficiency, said Saad.

"We and others have shown that long-term testosterone therapy, especially when it is done with injections and provided that medication adherence is high, results in sustainable weight loss," he said. " on management of obesity by the American Association of Clinical Endocrinology recommend measuring testosterone levels in men with obesity and, if testosterone levels are low, to consider testosterone therapy."

At baseline, patients' average age was largely similar between the testosterone and control groups (60.3 vs 61.6 years, respectively), as was their mean weight (129.6 vs 141.5 kg) and testosterone levels (265 vs 276 ng/dL). Follow-up was an average 9.4 years for the therapy group and 5.8 years for the controls.

In the testosterone group, seven patients lost at least 30% of their body weight, 34 patients lost at least 20%, and 45 lost at least 10%. All patients on testosterone lost at least 5% of their body weight. By contrast, only one of the 14 patients in the control group lost at least 5%.

Of the six patients who died in the therapy group, none were due to myocardial infarction or stroke. Of the nine deaths among the controls, six were related to cardiovascular events.

Saad said the statistics represent a new update of a larger, real-world, observational study of obese men with hypogonadism that began almost 15 years ago at a urology office in Germany. The study registered men with testosterone levels below 350 ng/dL, or 12.1 nmol/L, who gave consent to have their data analyzed. Men opting for treatment received three monthly injections of testosterone undecanoate following an initial 6-week interval.

Why did some of the men decline therapy? Some consulted their family practitioners and decided against it, Saad said.

"There still are concerns with testosterone therapy potentially causing prostate cancer or an increase cardiovascular risk," he said. "Although these concerns have never been substantiated -- as a matter of fact, the opposite may be true -- the perception is still there."

The new results, 13 years into the trial, focus on the men with extreme obesity. In 2020, researchers on the study as a whole, which includes normal, overweight, and obese men. Earlier this year, they also focusing on study participants with type 2 diabetes.

The new findings mesh with current understanding of the effect of testosterone therapy on weight loss, Saad said.

Saad noted that while bariatric surgery is "a well-proven treatment for excessive obesity," it also "requires life-long nutritional supplementation and has some risks. Bariatric surgery may not be feasible or available for everyone. With long-term testosterone therapy, we have seen comparable results, and long-term testosterone therapy should be considered for men as an alternative for bariatric surgery."

  • author['full_name']

    Randy Dotinga is a freelance medical and science journalist based in San Diego.

Disclosures

The study was initially unfunded and later funded by Bayer AG, which provided the testosterone injections. Saad is a consultant to and former employee of Bayer AG. Two other co-investigators received compensation and travel grants from the company.

Primary Source

ObesityWeek

Saad F "Effects of long-term testosterone therapy in men with functional hypogonadism and obesity" ObesityWeek 2022; Poster 171.