Overview of systematic reviews of non-pharmacological interventions in women with polycystic ovary syndrome

BACKGROUND Polycystic ovary syndrome (PCOS) is a major contributor to subfertility, diabetes and cardiovascular disease in women. The role of non-pharmacological interventions to prevent these outcomes has been reported in many systematic reviews, but robust conclusions have not been made due to variations in the scope, quality and findings of these reviews. OBJECTIVE AND RATIONALE Our aim was to provide an overview of existing evidence on the effects of non-pharmacological interventions in women with PCOS on fertility and non-fertility outcomes by a review of existing systematic reviews. SEARCH METHODS We reviewed systematic reviews of randomized trials that have evaluated the effects of non-pharmacological interventions, such as lifestyle interventions, nutritional supplements or alternative medicine therapies in women with PCOS on fertility, endocrine, glycaemic and weight-related outcomes. We assessed the quality of systematic reviews with the AMSTAR tool, and reported the outcomes with regard to: fertility (live birth, clinical pregnancy, ovulation and menstrual cycle regularization); endocrine outcomes (Ferriman-Gallwey score, free androgen index, free testosterone and total testosterone levels); and glycaemic (fasting blood insulin, fasting blood glucose, homoeostatic model assessment) and weight-related (BMI) outcomes. We assessed the strength of evidence for significant outcomes as per the grading of recommendations assessment, development and evaluation (GRADE) system. OUTCOMES We found twelve eligible systematic reviews which included between three (143 women) and 27 randomized trials (2093 women). Four reviews assessed the effects of lifestyle interventions (diet, physical activity and/or behavioural interventions); four evaluated nutritional supplements (one each on n-acetylcysteine, omega-3 fatty acids, inositol and vitamin D); and four studied alternative medical therapies (Chinese herbal medicine and acupuncture). All of the included reviews were of high quality and scored between 8 and 11 with the AMSTAR tool (with a maximum score of 11). Randomized evidence is lacking for live birth rate. N-acetylcysteine, inositol and the addition of alternative medicine to ovulation induction agents show preliminary potential to improve fertility (odds ratios (OR) for clinical pregnancy rate range from 1.99 to 4.83). Lifestyle interventions show benefits in improving hirsutism (mean difference (MD): -1.01 to -1.19). Lifestyle interventions (MD: -1.10 to -2.02), inositol (MD: -2.1) and acupuncture (MD: -1.90 to -3.43) all show some evidence of improvement in glycaemic outcomes and there is some evidence of reduced BMI with lifestyle interventions (MD: -0.15 to -1.12). All of these outcomes scored either low or very low quality of evidence on the GRADE score. WIDER IMPLICATIONS Lifestyle interventions in women with PCOS appear to improve glycaemic results, androgenic symptoms and anthropometric outcomes. The role of inositol and N-acetylcysteine in women with PCOS needs further evaluation. Large primary trials on all interventions are needed for an agreed set of core outcomes.