Circulatory metastin/kisspeptin-1 in polycystic ovary syndrome: a systematic review and meta-analysis with diagnostic test accuracy.

Research Question: A close association between Kisspeptin-1 (KISS-1) and reproductive physiology has been reported, but the results on circulatory KISS-1 are ambiguous in patients with polycystic ovary syndrome (PCOS). A systematic review and meta-analysis were conducted to evaluate the association between KISS-1 and PCOS, and to test its diagnostic test accuracy (DTA) through DTA meta-analysis.

Design: Relevant studies were identified by searching PubMed and other databases in addition to manual searching of cross-references. Random-effects model was used to obtain standardized mean differences (SMD), pooled correlation coefficients and summary of DTA. Meta-regression and sub-group analyses were conducted to explore heterogeneity. The presence of publication bias was tested using funnel plot analysis.

Results: This meta-analysis finally included 12 studies. Compared with controls, women with PCOS showed significantly increased circulatory KISS-1 levels (SMD = 0.47; P = 0.002). Meta-analysis of correlations showed positive associations between KISS-1 and anti-Müllerian hormone (AMH) (P = 0.03), testosterone (P < 0.001) and dehydroepiandrosterone (P = 0.004). The pooled diagnostic odds ratio and area under curve were 13.71 and 0.835, respectively. A one-study leave-out sensitivity analysis indicated that no single study had a significant influence on the overall outcome, suggesting the robustness of this meta-analysis.

Conclusions: This meta-analysis showed significantly increased KISS-1 level in PCOS, and its association with AMH reflects its role in reproductive physiology. In our DTA meta-analysis, KISS-1 showed good accuracy for PCOS detection. Further large-scale studies are required to establish its validity.