‘Positive’ Hormone Changes Found With Weight Loss in Obesity

TOPLINE:

In middle-aged patients with severe obesity, changes in endogenous sex hormones may be proportional to the amount of weight loss after bariatric surgery and dietary intervention, leading to an improved hormonal balance, with more pronounced androgen changes in women.

METHODOLOGY:

• Obesity-related hormonal imbalances are common among those seeking weight loss treatment.
• This prospective observational study evaluated the incremental effect of weight loss by three bariatric procedures and a dietary intervention on endogenous sex hormones in men and women over 3 years.
• The study included 61 adults (median age, 50.9 years; baseline mean body mass index, 40.2; 72% women) from obesity clinics and private bariatric services in Sydney, Australia, between 2009 and 2012, who underwent bariatric surgery or received dietary interventions based on their probability of diabetes remission.
• The researchers evaluated weight loss and hormone levels at baseline and at 6, 12, 24, and 36 months.
• Changes in hormones were also compared among patients who received dietary intervention and those who underwent bariatric procedures such as Roux-en-Y gastric bypass, sleeve gastrectomy, and laparoscopic gastric banding.

TAKEAWAY:

• For each kilogram of weight lost over 36 months, the total testosterone levels increased by 0.6% (95% CI, 0.2%-1.0%) in men and decreased by 0.8% (95% CI, −1.4% to −0.3%) in women.
• In women, testosterone levels decreased and sex hormone–binding globulin (SHBG) levels increased at 6 months; these changes were maintained at 24 and 36 months and remained statistically significant when controlled for age and menopausal status.
• In men, testosterone levels were significantly higher at 12, 24, and 36 months, and SHBG levels increased at 12 and 24 months. There were no differences in the estradiol levels among men and women.
• Women who underwent Roux-en-Y gastric bypass surgery experienced the greatest weight loss and the largest reduction (54%) in testosterone levels (P = .004), and sleeve gastrectomy led to an increase of 51% in SHBG levels (P = .0001), all compared with dietary interventions. In men, there were no differences in testosterone and SHBG levels between the diet and surgical groups.

IN PRACTICE:

“Ongoing monitoring of hormone levels and metabolic parameters is crucial for patients undergoing bariatric procedures to ensure long-term optimal health outcomes,” the authors wrote.

SOURCE:

This study was led by Malgorzata M. Brzozowska, MD, PhD, University of New South Wales Sydney, Sydney, Australia, and was published online in the International Journal of Obesity.

LIMITATIONS:

The main limitations were a small sample size, lack of randomization, and absence of data on clinical outcomes related to hormone changes. Additionally, the researchers did not evaluate women for polycystic ovary syndrome or menstrual irregularities, and the clinical significance of testosterone reductions within the normal range remains unknown.

DISCLOSURES:

The study was funded by the National Health and Medical Research Council. Some authors have received honoraria and consulting and research support from various pharmaceutical companies.