In severe obesity, bariatric surgery induces rapid reversal of hypogonadism

Marco Rossato

Men with severe obesity and hypogonadism who underwent sleeve gastrectomy experienced a marked increase in testosterone and prostate-specific antigen and a reduction in serum estradiol during the 1 month following the procedure, according to findings presented at the European Congress on Obesity annual meeting.

“Obese adult males have a high prevalence of hypogonadism leading to infertility, libido decrease and erectile dysfunction,” Marco Rossato, MD, PhD, an endocrinologist and andrologist at the University of Padova School of Medicine in Italy, told Endocrine Today. “We wanted to verify the prevalence of hypogonadism in obese males and the effects of a rapid weight reduction by bariatric surgery to testicular function rescue.”

In an observational study, Rossato and colleagues analyzed data from 29 men with a mean BMI of 43.4 kg/m² in the 1 month before and 1 month after sleeve gastrectomy (mean age, 41 years) and a group of 19 healthy age-matched men (controls). Researchers measured total testosterone, dihydrotestosterone, estradiol, luteinizing hormone, follicle-stimulating hormone, sex hormone-binding globulin, prostate-specific antigen and leptin in both groups of men at baseline and after surgery.

In the surgery group, 51.6% of men had hypogonadism, and 45.2% of those men had metabolic syndrome. Compared with the lean, healthy men, men in the surgery group had reduced mean total testosterone (10.8 nmol/L vs. 15.7 nmol/L; P < .05), higher mean plasma estradiol levels (124.4 pmol/L vs. 78.7 pmol/L; P < .01) and higher mean luteinizing hormone and follicle-stimulating hormone levels (P < .05 for both).

At 1 month after surgery, the men lost a mean 17.2 kg and only 11.6% had hypogonadism, according to researchers. Testosterone levels for the cohort rose to a mean of 18.9 pmol/L, prostate-specific antigen levels rose from a mean of 0.74 µg/L to 1 µg/L and mean estradiol levels fell to 96.1 pmol/L.

The researchers noted that the findings must be confirmed in a larger cohort with longer follow-up, taking weight maintenance into account.

“Body weight reduction, through fat mass reduction, reverses hypogonadism,” Rossato said. “The faster the body weight reduction is, the faster rescue from hypogonadism.”
Rossato said he next plans to verify the effects of testosterone supplementation in hypogonadal adult men on adipose tissue distribution and body weight variations. – by Regina Schaffer

For more information:

Marco Rossato, MD, PhD, can be reached at the University of Padova School of Medicine, Department of Medicine, Via Giustiniani, 2 – 35128, Padova, Italy; email: marco.rossato@unipd.it.

Reference:

Rossato M, et al. Abstract #T4P58. Presented at: European Congress on Obesity; May 23-26, 2018; Vienna.

Disclosure: Rossato reports no relevant financial disclosures.