Hypogonadal men receiving testosterone therapy may experience significant and sustained weight loss, researchers reported online in Clinical Obesity.
In a study, men lost an average of 10.5% of their baseline body weight after five years of treatment. Over the same period, their mean body mass index (BMI) fell from 31.6 to 29.4 kg/m2.
The study involved 261 men with a mean age of 59.5 years who presented to a single urologist complaining of erectile dysfunction. They also had a range of common comorbidities, including benign prostatic hyperplasia/lower urinary tract symptoms (57%), hypertension (45%), dyslipidemia (33%), and type 2 diabetes (31%).
All subjects received parenteral testosterone undecanoate 1,000 mg at baseline, again six weeks later, and then every 12 weeks for up to five years.
The two investigators, Aksam Yassin, MD, of the Segeberger Kliniken, Norderstedt, Germany, and Gheorghe Doros, PhD, of the Boston University School of Public Health, found that the men’s average testosterone levels rose from 7.72 nmol/L at baseline to 16.2 nmol/L within the first year of therapy, and plateaued at 18-19 nmol/L
At the start of treatment, 162 men (62%) had a BMI of 30 kg/m2 or higher and 88 (34%) had a BMI of 25-25.9 kg/m2. In addition, 179 (69%) had a waist circumference (WC) greater than 102 cm and 74 (28%) had a WC of 94-101.9 cm.
The men experienced a mean weight loss of 11.1 kg or 10.5% of their initial weight, and the loss occurred linearly over five years. Results showed that 14% of patients lost 20 kg more, 31% lost 15 kg or more, 51% lost 10 kg or more, and 80% lost 5 kg or more. Four percent gained weight.
Concomitantly, WC declined in 97.5% of men. The mean reduction was 9.4 cm and occurred in a linear fashion during the study period. In addition, 84% had a WC decrease of 5 cm or more, 48% had at least a 10 cm drop, and 15% had at least a 15 cm reduction. WC increased in 2% of the men.
Furthermore, subjects’ mean BMI dropped from 31.7 kg/m2 at baseline to 30.6 kg/m2 after one year, 29.9 kg/m2 at two years, 29.5 kg/m2 at three years, and 29.4 kg/m2 at both four and five years.
The men who were obese at the start of the study period experienced the greatest reductions in body weight, waist circumference and BMI.
“We may have found at least a partial solution for obese hypogonadal men,” said Farid Saad, MD, of Global Medical Affairs-Andrology at Bayer Pharma, Berlin, which funded the study. “While one would usually prefer a controlled study, here we have very robust data in an unselected group of patients who did not even have the intention to lose weight.”