Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder in women, therapeutic methods include reducing obesity, hyperandrogenism and insulin resistance. This paper sorts out data from a clinical study that contains 83 Chinese PCOS patients in Control group, and 87 in Metformin group and analyzes the variation of parameters between baseline and after 4-month treatment. The Wilcoxon signed-rank test shows Metformin has a significant effect on obesity, hyperandrogenism and insulin resistance. They are measured by BMI, FAI and HOMA-IR respectively. The Spearman correlation analysis shows ΔFAI (variation after 4 months) is a mediator that is strongly correlated with ΔBMI and ΔHOMA-IR variation in PCOS patients. Linear regression concludes it as 10.64ΔBMI~ΔFAI~10.20ΔHOMA-IR. Metformin treatment has a stronger effect on decreasing HOMA-IR and BMI than FAI, as the relationship turns to 4.17ΔBMI~ΔFAI~5ΔHOMA-IR. This study fills the gap left by previous research which rarely focused on relationship of characteristic changes in PCOS patients, further explains Metformin treatment mechanism in evidence-based medicine perspective and provides strategy for new use of old medicine.
