PCOS in Morbidly Obese May Be Reversible With Bariatric Surgery
News Author: Karla Gale, MS
CME Author: Charles Vega, MD, FAAFP
Dec. 16, 2005 — Weight loss following bariatric surgery in morbidly obese women with polycystic ovary syndrome (PCOS) can normalize the metabolic, hyperandrogenic and reproductive abnormalities that accompany this syndrome, Spanish investigators report.
“Our findings indicate reversibility of PCOS in morbidly obese women in response to normalization of insulin sensitivity after sustained weight loss,” lead investigator Dr. Hector F. Escobar-Morreale told Reuters Health. “This suggests that the mechanism underlying PCOS in obese women is possibly quite different compared to those of lean individuals, in whom insulin resistance may be a much less important factor.”
Dr. Escobar-Morreale and colleagues at Hospital Ramon Y Cajal in Madrid performed bariatric surgery on 36 premenopausal women for whom noninvasive weight loss strategies had failed. Seventeen were diagnosed with PCOS, a frequent finding in morbidly obese women.
After excluding seven patients who had been previously diagnosed with PCOS, the researchers estimate that 35% of the patients had undiagnosed PCOS, a nearly seven-fold increased prevalence compared with that in unselected female blood donors from Madrid.
They report the patients’ outcomes in the December issue of the Journal of Clinical Endocrinology and Metabolism.
Among the 12 women with PCOS who were available for follow-up, the syndrome resolved after the marked weight loss achieved after surgery (mean, 41 kg after a mean of 12 months). Regular menstrual cycles were restored in all 12, and luteal phase serum progesterone concentrations of 4 ng/mL or higher confirmed that they were ovulating.
Elevated fasting insulin levels, observed only in those with PCOS preoperatively, returned to the reference range after weight loss, as did hormone levels.
Dr. Escobar-Morreale recommends that all morbidly obese women be screened for PCOS, thereby preventing “reproductive complications of PCOS (infertility, endometrial hyperplasia/carcinoma) and permitting treatment of cutaneous symptoms.”
He advises that screening include “clinical history, physical examination including hirsutism score, serum total testosterone and sex hormone binding globulin (SHGB) levels to calculate free testosterone concentration, and evaluation of ovulatory dysfunction by using luteal phase progesterone levels or basal body temperature charts.”
“Based on the excellent response in our series, follow-up without specific treatment would be enough,” he added. “Pharmacologic treatment (antiandrogens and/or insulin sensitizers) should only be considered if symptoms of PCOS persist after sustained weight loss.”
J Clin Endocrinol Metab. 2005;90:6364-6369
Reuters Health Information 2005. © 2005 Reuters Ltd.
Learning Objectives for This Educational Activity
Upon completion of this activity, participants will be able to:
List conditions associated with PCOS that can be ameliorated with weight loss.
Identify elements of PCOS improved after bariatric surgery.
The main physiological defect of PCOS is the secretion of inappropriate levels of androgen by the ovaries. Most patients with PCOS have obesity, and nearly half of patients can be diagnosed with the metabolic syndrome. While weight loss through conservative measures can improve the hyperandrogenism, menstrual dysfunction, and insulin resistance associated with PCOS, the authors of the current study note that only approximately 20% of patients with obesity will maintain a 10% weight loss after 12 months of conservative measures.
As sustained weight loss is difficult for many patients, bariatric surgery has an increasing role for obese adults. The authors of the current study examine the prevalence of PCOS among women presenting for bariatric surgery as well as whether this surgery might improve some of the markers of this syndrome.
Premenopausal women undergoing bariatric surgery at 1 Spanish academic center were recruited for study participation. All subjects had a body mass index of 40 kg/m2 or greater or 35 kg/m2 or greater along with significant comorbidity.
PCOS was diagnosed at baseline according to standard criteria for oligoovulation and hyperandrogenism, which was not explained by other endocrine abnormalities.
The authors followed up patients with preoperative PCOS for up to 26 postoperative months. Subjects were evaluated for the degree of hirsutism, free testosterone levels, insulin levels and insulin resistance, and measures of androstenedione, 17-hydroxyprogesterone, and dehydroepiandrosterone.
36 women participated in the trial. All were white, and 17 (47%) had PCOS. Another 5 women had elevated androgen levels at baseline but regular menses. PCOS had been previously undiagnosed in 35% of the patient sample.
Patients with and without PCOS were similar in terms of body mass index, waist circumference, waist-to-hip ratio, blood pressure, and pulse rate. Patients with PCOS were slightly younger than women without PCOS (29.8 vs 33.9 years old, respectively). Insulin resistance was more common among women with PCOS. 2 subjects with PCOS had diabetes, and 2 had hypertension.
Of the 17 women with baseline PCOS, 12 were available for follow-up. These subjects were followed up for a mean of 12 months after surgery. 2 women were disqualified because of use of oral contraceptives, while 1 patient died after surgery and another developed an eating disorder.
The mean weight loss after 12 months of follow-up was 41 kg.
All study parameters were improved following bariatric surgery, including the degree of hirsutism. Regular menstrual cycles were returned in all 12 subjects, and it appeared all of these women were ovulating regularly as evaluated by luteal phase progesterone concentrations. Measures of free testosterone, androstenedione, 17-hydroxyprogesterone, and dehydroepiandrosterone were improved in all but 1 patient.
Mean levels of SHBG increased after bariatric surgery.
Fasting insulin levels and measures of insulin resistance were improved in the 12 months after bariatric surgery.
Diabetes and hypertension resolved in 1 patient each following surgery.
No patient met criteria for PCOS 1 year after bariatric surgery.
Pearls for Practice
Weight loss may improve hyperandrogenism, insulin resistance, and menstrual dysfunction associated with PCOS, but, in general, only a minority of patients can maintain weight loss through conservative measures.
In the current small study, no woman with PCOS undergoing bariatric surgery met criteria for the syndrome 1 year postoperatively. Measures of serum androgens, insulin resistance, and hirsutism were improved following bariatric surgery.
Reuters Health Information 2005. © 2005 Reuters Ltd.