Treating polycystic ovary syndrome: Start using dual medical therapy

Using the Rotterdam criteria, the diagnosis of polycystic ovary syndrome (PCOS) is made in the presence of 2 of the following 3 criteria¹:

1. oligo-ovulation or anovulation
2. hyperandrogenism manifested by the presence of either hirsutism or elevated hormone levels (including serum testosterone androstenedione and/or dehydroepiandrosterone sulfate)
3. ultrasonography evidence of multifollicular ovaries (≥12 follicles with a diameter of 2 mm to 9 mm in one or both ovaries; FIGURE) or ovarian stromal volume of 10 mL or more.

Illustration: Kimberly Martens for OBG Management

Among reproductive-age women, the prevalence of PCOS has been reported to range from 8% to 13% for different populations.² Most clinicians initiate treatment for PCOS with oral estrogen−progestin (OEP) monotherapy. OEP treatment has many beneficial hormonal effects, including:

• a resulting decrease in pituitary luteinizing hormone (LH) secretion, which decreases ovarian androgen production
• an increase in liver production of sex hormone−binding globulin (SHBG), which decreases free testosterone levels
• protection against the development of endometrial hyperplasia
• induction of regular uterine withdrawal bleeding.

However, OEP therapy neither improves metabolic indices (insulin sensitivity and visceral fat secretion of adipokines) nor blocks androgen action in the skin.

Dual medical treatment for PCOS can address the issues that monotherapy cannot and, along with providing guidance on improving diet and exercise, many experts support the initial therapy of PCOS with dual medical therapy (OEP plus metformin or spironolactone).

Advantages of OEP plus metformin

For many women with PCOS, the syndrome is characterized by abnormalities in both the reproductive (increase in LH secretion) and metabolic (insulin resistance and increased adipokines) systems. OEP monotherapy does not improve the metabolic abnormalities of PCOS. Combination treatment with both OEP plus metformin, along with diet and exercise, can best treat these combined abnormalities.

Data support dual therapy with metformin. In one small, randomized trial in women with PCOS, OEP plus metformin (1,500 mg daily) resulted in a greater reduction in serum androstenedione and a greater increase in SHBG than OEP monotherapy.³ In addition, weight loss and a reduction in waist-to-hip ratio only occurred in the OEP plus metformin group.³ In another small randomized study in women with PCOS, OEP plus metformin (1,500 mg daily) resulted in a greater decrease in free androgen index than OEP monotherapy.⁴

In my clinical opinion, women who may best benefit from OEP plus metformin therapy have one of the following factors indicating the presence of insulin resistance⁵:

• body mass index >30 kg/m²
• waist-to-hip ratio ≥0.85
• waist circumference >35 in (89 cm)
• acanthosis nigricans
• personal history of gestational diabetes
• family history of type 2 diabetes mellitus (T2DM) in a first-degree relative
• diagnosis of the metabolic syndrome.

My preferred treatment approach

Metformin is a low cost and safe treatment for metabolic dysfunction due to insulin resistance and excess adipokines. I often start PCOS treatment for my patients with an OEP plus metformin extended release (XR) 750 mg with dinner. If the patient tolerates this dose, I increase the dose to metformin XR 1,500 mg with dinner.

Adverse effects. The most common side effects of metformin are gastrointestinal, including abdominal discomfort, flatulence, borborygmi, diarrhea, and nausea. Metformin reduces serum vitamin B12 levels by 5% to 10%; therefore, ensuring adequate vitamin B12 intake (2.6 µg daily) is helpful.⁶ Although metformin does reduce vitamin B12 levels, there is no strong relationship between metformin and anemia or peripheral neuropathy.⁷ Lactic acidosis is a rare complication of ­metformin.

Beneficial effects. In the treatment of PCOS, metformin may have many beneficial effects, including⁸:

• decrease in insulin resistance
• decrease in harmful adipokines
• reduction in visceral fat
• reduction in the incidence of T2DM.

OEP plus spironolactone

Many women with PCOS have increased LH secretion and increased androgen activity in the skin due to increased 5-alpha reductase enzyme activity, which catalyzes the conversion of testosterone to the powerful intracellular androgen dihydrotestosterone.⁹ Women with PCOS may present with a chief problem report of hirsutism, acne, or female androgenetic alopecia. OEP plus spironolactone may be an optimal initial treatment for women with a dominant dermatologic manifestation of PCOS. OEP treatment results in a decrease in pituitary LH secretion and ovarian androgen production. Spironolactone adds to this therapeutic effect by blocking androgen action in the skin.

The data on dual therapy with spironolactone. Many dermatologists recommend spironolactone in combination with cosmetic measures for the treatment of acne, but there are only a few randomized trials that demonstrate its efficacy.¹⁰ In one trial spironolactone was demonstrated to be superior to placebo for the treatment of inflammatory acne.¹⁰ Authors of multiple randomized trials report that the antiandrogens, spironolactone, or finasteride are superior to metformin to treat hirsutism.¹¹ In addition, a few small trials report that spironolactone plus OEP is superior to either OEP or metformin monotherapy for hirsutism.¹¹ Clinical trials of spironolactone for hirsutism have been rated as “low quality” and additional controlled trials of OEP monotherapy versus OEP plus spironolactone are ­warranted.¹²