Different supplements improve insulin resistance, hormonal functions, and oxidative stress on overweight and obese women with polycystic ovary syndrome: a systematic review and meta-analysis

Objectives: To investigate various supplements that improve insulin resistance, hormonal status, and oxidative stress in overweight or obese women with polycystic ovarian syndrome (PCOS).

Methods: A literature search was conducted on four different databases, which led to the discovery of twenty - five randomized controlled trials (RCTs). These RCTs evaluated the efficacy of various supplements in improving insulin resistance (IR), hormonal status, and oxidative stress among overweight or obese women diagnosed with PCOS. Subsequently, data extraction and analysis were carried out to determine the quality of the study's methodological design and the potential for bias. Moreover, a meta-analysis was performed using the data from the RCTs.

Results: A total of 25 RCTs were carried out, and 1636 women were enrolled. All participants were overweight or obese. The standardized mean differences (SMD) were as follows: For fasting plasma glucose (FPG), it was -0.34 (95% confidence interval [CI], -0.49 to -0.19, p = 0.123, I² = 30.8%); for insulin, it was -0.67 (95% CI, -0.83 to -0.52, p = 0.208, I² = 24%); for fasting insulin (FI), it was -0.26 (95% CI, -0.52 to -0.00, p = 0.269, I² = 21.9%); for homeostatic model assessment-insulin resistance index (HOMA-IR), it was -0.59 (95% CI, -0.73 to -0.45, p = 0.015, I² = 48.7%); for homoeostatic model assessment beta - cell function (HOMA-B), it was -0.51 (95% CI, -0.75 to -0.27, p = 0.547, I² = 0%); for quantitative insulin sensitivity check index (QUICKI), it was 0.94 (95% CI, 0.76 to -1.12, p = 0.191, I² = 27.5%); for total testosterone, it was -0.61 (95% CI, -1.14 to -0.09, p = 0.00, I² = 78.5%); for testosterone, it was -0.38 (95% CI, -0.86 to 0.10, p = 0.03, I² = 71.5%); for follicle - stimulating hormone (FSH), it was 0.16 (95% CI, -0.08 to 0.40, p = 0.470, I² = 0%); for luteinizing hormone (LH), it was -0.56 (95% CI, -1.32 to 0.20, p = 0.000, I² = 91.1%); for sex hormone - binding globulin (SHBG), it was 0.35 (95% CI, 0.02 to 0.69, p = 0.000, I² = 78%); for dehydroepiandrosterone (DHEAS), it was -0.27 (95% CI, -0.76 to 0.21, p = 0.001, I² = 78.7%); for plasma total antioxidant capacity (TAC), it was 0.87 (95% CI, 0.45 to 1.30, p = 0.004, I² = 71.3%); for plasma malondialdehyde (MDA), it was -0.57 (95% CI, -0.79 to -0.36, p = 0.992, I² = 0.0%).

Conclusion: This study's findings indicate that, in comparison with a placebo, supplements have a favorable effect on IR, hormonal functions, and oxidative stress in PCOS. Nevertheless, it is crucial to note that the above-drawn conclusions need to be verified by more high-quality studies, given the limitations regarding the number and quality of the included studies.