Delta neutrophil index in obese and non-obese polycystic ovary syndrome patients

Objective We aimed to evaluate the usefulness of delta neutrophil index (DNI), a new inflammatory marker, in polycystic ovary syndrome (PCOS). Methods This retrospective case-control study was conducted at a tertiary health center. The DNI and other blood parameters obtained from the complete blood count examination of 227 individuals, consisting of 72 PCOS patients and 155 controls, were compared between the two groups. A receiver operating characteristic analysis was performed to examine the relationship between DNI and PCOS. Results DNI, white blood cell (WBC) count, and neutrophil count were significantly higher in the PCOS group than in the control group (P=0.028, 0.011, and 0.037; respectively). DNI and WBC counts were significantly higher in nonobese-PCOS patients (P=0.018 and 0.041; respectively). When the obese-PCOS and obese-control groups were compared, only neutrophil count was significantly higher in obese-PCOS patients (P=0.016). Significance was observed at cut-off values of 0.015 (area under the curve [AUC]=0.588) (P=0.034; sensitivity, 78%; specificity, 35%; Youden’s index=0.133) for DNI: 9.35 (AUC=0.594) (P=0.022) for WBC; and 5.38 (AUC=0.628) (P=0.002) for neutrophils. Conclusion Higher DNI in PCOS patients and similar results in the non-obese-PCOS group were observed when obese and non-obese-PCOS patients were considered separately. However, the lack of difference in the obese-PCOS group strengthens the hypothesis that there is obesity-independent inflammation in PCOS.