Inflammatory status and clinical phenotypes of PCOS: the role of NLR, SII, SIRI, and AISI.

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder in women of reproductive age, often associated with low-grade chronic inflammation. This study aimed to investigate the relationship between composite inflammatory markers-Neutrophil-to-Lymphocyte Ratio (NLR), Systemic Immune Inflammation Index (SII), Systemic Inflammation Response Index (SIRI), and Aggregate Index of Systemic Inflammation (AISI)-and clinical phenotypes of PCOS, including oligo-/amenorrhea, hyperandrogenism, and polycystic ovarian morphology (PCOM).

METHODS

In this retrospective cross-sectional study, women with PCOS were categorized into subgroups based on clinical phenotypes. Composite inflammatory markers were calculated from complete blood count parameters, and their association with clinical, hormonal, and ultrasonographic findings was analyzed. ROC analysis assessed the discriminatory value of each marker.

RESULTS

Inflammatory markers were significantly higher in the oligo-/amenorrhea and PCOM groups. In oligo-/amenorrhea, NLR (2.42 vs. 1.96, p = 0.028), AISI (282.16 vs. 188.73, p = 0.005), SII (664.59 vs. 519.86, p = 0.008), and SIRI (0.97 vs. 0.70, p = 0.005) were elevated. In PCOM, NLR (2.85 vs. 2.25, p = 0.025), AISI (323.15 vs. 262.78, p = 0.049), SII (738.52 vs. 641.27, p = 0.030), and SIRI (1.10 vs. 0.90, p = 0.046) were also higher. AISI showed the best discrimination for oligo-/amenorrhea (AUC = 0.652), while NLR was most predictive for PCOM (AUC = 0.617).

CONCLUSIONS

Composite inflammatory markers are elevated in specific PCOS phenotypes, especially oligo-/amenorrhea and PCOM, and may reflect low-grade inflammation. These markers may help identify patients at higher cardiometabolic risk and guide preventive strategies.