Trial With Metformin in Women With Polycystic Ovary Syndrome
Condition: Polycystic Ovary Syndrome
MeSH terms: Polycystic Ovary Syndrome; Syndrome
Study type: Interventional
Phase: Phase 4

Summary: 
      The investigators wanted to elucidate the effects of metformin in Polycystic Ovary Syndrome
      (PCOS) by performing a randomized, double-blinded, placebo-controlled cross-over study.
    

Detailed description: 
      Eligible women who gave written informed consent were assigned to 6 months of treatment with
      either 850 mg of metformin or placebo twice daily, followed by a wash-out period of 3 months
      before cross-over to the alternate treatment for another 6 months. Randomization defining
      treatment sequence was done at inclusion by random number tables. The appearance of the
      tablets was identical, and patients and investigators were blinded to treatment allocation.
      The randomization code was stored in a closed envelope until all participants had finished
      the treatment. Participants were seen by one of the investigators before inclusion and every
      second month during treatment periods, always in the morning after an overnight fast of at
      least 8 h. They were weighed wearing light clothing. Waist circumference was measured at the
      umbilical level and hip circumference at the trochanter region. Systolic and diastolic blood
      pressure was measured with a semiautomatic blood pressure monitor and a blood sample was
      drawn for immediate analysis without respect to bleeding periods. All participants registered
      their bleeding periods in a calendar during both study periods and the 3 months wash-out
      period. Calculation of sample size was based on the assumption that at least 50% of the women
      would experience at least 30% more menstrual periods on metformin than on placebo. Based on a
      power of 90 (b = 0.10) to detect a significant difference [two-sided P-value of 0.05], the
      minimum sampling size was calculated to 44 subjects.

      We also assumed a 10% drop-out rate, and thus aimed at including 50 women. As drop-out rate
      quickly rose higher than expected, we decided to include 60 women. In the intention-to-treat
      analysis, the values of each participant after 6 months of metformin or placebo were compared
      with the baseline values. Linear regression analysis with the changes in testosterone and
      homeostasis model assessment (HOMA) index as dependent variables was performed to examine
      potential relations between the changes. The per protocol analysis included data from
      participants completing both study periods, i.e. the difference between the values of each
      participant after placebo and metformin, respectively, was calculated, and a significance
      test performed on the differences.
    

Intervention name(s): Metformin; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): Metformin 1500 mg (=2 pills) per day in six months; 2 pills per day in six months; pills look like metformin pills
Intervention MeSH terms: Metformin
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Treatment
Keywords: PCOS; metformin; obesity; randomized controlled trial