ROLE OF INSULIN SENSITIZERS ON CARDIOVASCULAR RISK FACTORS IN POLYCYSTIC OVARIAN SYNDROME: A META-ANALYSIS

Abstract

Objective: Polycystic ovarian syndrome (PCOS) is associated with an increase in cardiovascular (CV) risk factors such as insulin resistance, with accompanying hyperinsulinemia and hyperlipidemia, which are predisposing factors for type 2 diabetes mellitus and CV disease. The aim of this meta-analysis is to examine the effect of insulin sensitizers on clinical and biochemical features of PCOS and risk factors for CV disease.

Methods: A systematic literature review was conducted, and randomized controlled clinical trials were identified by a search of bibliographic databases: Medline database (from 1966 forward), EMBASE (January 1985 forward), and Cochrane Central Register of Controlled Trials. Reviews of reference lists further identified candidate trials. Data was independently abstracted in duplicate by 2 investigators using a standardized data-collection form. Articles without a comparison group and randomization allocation were excluded. Reviewers worked independently and in duplicate to determine the methodological quality of trials, then collected data on patient characteristics, interventions, and outcomes.

Results: Of 455 studies, 44 trials were eligible. A random effects model was used. Significant unadjusted results favoring treatment with insulin sensitizers were obtained for body mass index (BMI) (effect size [ES] of 0.58), waist to hip ratio (WHR) (ES of 0.02), low-density-lipoprotein cholesterol (LDL-C) (ES of 0.11), fasting insulin (ES of 2.82), fasting glucose (ES of 0.10), free testosterone (ES of 1.88), and androstenedione level (ES of 0.76).

Conclusion: Treatment with insulin sensitizers in women with PCOS results in improvement in CV factors such as BMI, WHR, LDL-C, fasting insulin, glucose, free testosterone, and androstenedione.

Fig. 1.

Flowchart of study selection. RCT = randomized controlled trial.

Fig. 2.

Forest plot of effect size for all the variables for studies using metformin and thiazolidinediones. BMI = body mass index; CI = confidence interval; DHEAS = dehydroepiandrosterone sulfate; ES = effect size; FSH = follicle-stimulating hormone; HDL = high-density lipoprotein; LDL = low-density lipoprotein; LH = luteinizing hormone.

Fig. 3.

Forest plot for the variable waist to hip ratio for studies using both metformin and thiazolidinediones. CI = confidence interval; ES = effect size.

Fig. 4.

Forest plot of adjusted effect size for all the variables for the studies using metformin in the treatment arm. BMI = body mass index; CI = confidence interval; DHEAS = dehydroepiandrosterone sulfate; ES = effect size; FSH = follicle-stimulating hormone; HDL = high-density lipoprotein; LDL = low-density lipoprotein; LH = luteinizing hormone.

Fig. 5.

Forest plot of adjusted effect size for all the variables for the studies using thiazolidinediones in the treatment arm. BMI = body mass index; CI = confidence interval; DHEAS = dehydroepiandrosterone sulfate; ES = effect size; FSH = follicle-stimulating hormone; HDL = high-density lipoprotein; LDL = low-density lipoprotein; LH = luteinizing hormone.