Inositol is an effective and safe treatment in polycystic ovary syndrome: a systematic review and meta-analysis of randomized controlled trials.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 36703143 · doi:10.1186/s12958-023-01055-z
What was done
A systematic review and meta-analysis was conducted across CENTRAL, MEDLINE, and Embase through October 20, 2021 (PROSPERO CRD42021283275). Eligible randomized controlled trials (RCTs) evaluated women with polycystic ovary syndrome (PCOS) randomized to any form of inositol versus metformin or placebo. The primary outcome was menstrual cycle normalization; secondary outcomes included body mass index (BMI), carbohydrate metabolism markers, and hyperandrogenism parameters.
What was found
Across 26 RCTs involving 1,691 patients (806 inositol, 311 placebo, 509 metformin), inositol was associated with a higher likelihood of regular menstrual cycles compared to placebo (risk ratio 1.79, 95% CI: 1.13 to 2.85) and demonstrated non-inferiority to metformin. Compared to placebo, inositol also produced greater reductions in BMI (mean difference [MD] -0.45, 95% CI: -0.89 to -0.02), free testosterone (MD -0.41, 95% CI: -0.69 to -0.13), total testosterone (MD -20.39, 95% CI: -40.12 to -0.66), androstenedione (MD -0.69, 95% CI: -1.16 to -0.22), fasting glucose (MD -3.14, 95% CI: -5.75 to -0.54), and AUC insulin (MD -2081.05, 95% CI: -2745.32 to -1416.78). Sex-hormone-binding globulin (SHBG) increased significantly with inositol versus placebo (MD 32.06, 95% CI: 1.27 to 62.85).
Why it matters
Inositol offers an effective, non-inferior alternative to metformin for cycle regularity and metabolic improvement in PCOS, providing a treatment option with potentially better tolerability.
Limits
The abstract pools all inositol types and dosages (such as myo-inositol versus D-chiro-inositol) without subgroup comparisons. Specific adverse event rates and direct quantitative comparisons with metformin beyond cycle regularity are not reported in the abstract.
Cited by
- supports Inositol decreases insulin resistance in women with PCOS.
- supports Inositol supplementation increases insulin sensitivity in patients with PCOS.
- supports Inositol supplementation is effective for managing polycystic ovary syndrome (PCOS).