Long-term results of correction of metabolic disorders in polycystic ovary syndrome after metformin treatment

Abstract

Background. Polycystic ovary syndrome (PCOS) is a polymorphic disease with an extremely variable clinical picture and different phenotypes, which is observed in 5–10 % of women of reproductive age. During the life of women with PCOS, the risk of developing type 2 diabetes mellitus is increased by 10 times, arterial hypertension and coronary heart disease — by 7 times, including myocardial infarction, and there was more than double risk of ovarian, endometrial and breast cancer. The purpose of the study was to analyze the dynamics of parameters of insulin resistance (IR), dyslipidemia, impaired glucose tolerance after metformin treatment in PCOS patients using Caro index and HOMA­IR. Materials and methods. Twenty­six case histories of patients with PCOS who were treated with metformin for the period from 2012 to 2018 for six months from the date of diagnosis were analyzed. In 2018, all patients underwent blood lipids study, a standard glucose tolerance test, and immunoreactive insulin content study in venous blood plasma. Carbohydrate metabolism was evaluated using the Caro index and HOMA­IR. Results. Metformin use in 26 women with PCOS and insulin resistance resul­ted in a significant fasting immunoreactive insulin decrease (from 21.4 ± 2.3 µIU/ml to 6.9 ± 0.8 µIU/ml; p = 0.005) in 6 months, while significant changes in the level of fasting glycemia were not observed. Accordingly, HOMA­IR decreased from 4.38 ± 1.26 to 1.17 ± 0.18 (p = 0.01), and the Caro index increased from 0.24 ± 0.05 to 0.58 ± 0.14 (p = 0.02). Assessment of lipid metabolism 6 months after initiation of metformin treatment confirmed a significant decrease in cholesterol level — from 5.4 ± 0.3 mmol/l to 3.6 ± 0.5 mmol/l (p = 0.01), and triglyceride content — from 1.7 ± 0.2 mmol/l to 0.8 ± 0.2 mmol/l (p = 0.03). A survey conducted in 2018 in the same patients showed an increase in body weight not only compared with indicators 6 months after metformin treatment, but also with baseline. There was a significant increase in cholesterol to 6.7 ± 0.4 mmol/l (p = 0.01 compared with indicator after the metformin treatment) during the 2018 survey. Conclusions. Women with PCOS and insulin resistance, central obesity, dyslipidemia are at highest risk of developing diabetes and cardiovascular pathology. Metformin is considered a potentially effective method to overcome insulin resistance, improve hormonal, biochemical parameters and possibly reduce cardiovascular risk in PCOS.