WASHINGTON — A combination of metformin and the oral contraceptive Ortho Tri-Cyclen improves lipid profiles more than does an oral contraceptive alone in patients with polycystic ovary syndrome, according to preliminary data from a small pilot study.
“Insulin resistance with compensatory hyperinsulinemia plays a critical role in PCOS,” Dr. Paulina Essah said at the annual meeting of the Androgen Excess and PCOS Society. “Traditionally, oral contraceptives have been the treatment for PCOS, but oral contraceptives may worsen or have no effect on insulin sensitivity. There are also very little data on the effects of the combination of metformin and oral contraceptives on insulin resistance and cardiovascular risk,” said Dr. Essah of the division of endocrinology and metabolism at Virginia Commonwealth University, Richmond.
In this randomized, double-blind, placebo-controlled study, Dr. Essah and colleagues assigned 17 women with PCOS to an oral contraceptive plus 500 mg of metformin three times daily or an oral contraceptive plus a placebo three times daily. Ortho Tri-Cyclen (ethinyl estradiol 35 mcg/norgestimate 0.25 mg) was chosen because it is commonly used in the United States, Dr. Essah said.
All subjects underwent 2-hour oral glucose tolerance testing, frequently sampled intravenous glucose tolerance testing, and brachial artery flow-mediated dilatation at baseline and after 3 months. The subjects' mean age was 24.9, and their mean body mass index was 33.7.
After 3 months, the researchers found no difference between the two groups in weight, BMI, fasting insulin, or fasting glucose measurements. However, the combination oral contraceptive-metformin group experienced a trend toward higher HDL cholesterol (55.6 vs. 47.6 mg/dL) and lower triglyceride levels (86.8 vs. 152.7 mg/dL) compared with the group that took oral contraceptives alone. The combination group also demonstrated a significant increase in acute insulin response to glucose.
The study was funded by the National Institutes of Health. Dr. Essah said she had no financial conflicts of interest.