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The results of a recent study showed that elevated neutrophil-to-lymphocyte ratio (NLR) and systemic immune inflammation index (SII) levels may be significantly associated with cystoid macular edema (CME). The elevated levels may indicate a higher incidence of CME in these patients,¹ according to researchers from the Department of Ophthalmology, Shantou University Medical College North Guangdong People’s Hospital, Guangdong, China. First author Wu Liao led the study published in International Ophthalmology.

The researchers conducted a retrospective study to assess serum inflammatory biomarkers in patients with different subtypes of diabetic macular edema (DME).

A total of 50 eyes from 37 treatment-naïve patients with DME were included in the study. All had received intravitreal injection therapy and optical coherence tomography (OCT) image processing.

Patients were then divided into 1 of 2 groups based on the imaging findings: 25 patients in the CME group and 25 in the diffuse retinal thickening (DRT) group. The study also included a control group consisting of 25 eyes with diabetic retinopathy without DME.

The investigators reviewed the best-corrected visual acuity (BCVA), central macular thickness (CMT), macular cube volume (VOL) and hematological examination. NLR, platelet-to-lymphocyte ratio (PLR) and SII were calculated, they said.

Analysis results

The investigators reported significantly higher NLR and SII levels in the CME group compared to the DRT and control groups (P< 0.01 for all comparisons).

Specifically, the optimal receiver operating characteristic (ROC) curve cut-off value for NLR for CME was 2.27, with 88.0% sensitivity and 68.0% specificity. The optimal ROC cutoff for SII for CME was 447.33, with 84.0% sensitivity and 60.0% specificity, they reported.

After the patients underwent an intravitreal injection, BCVA and VOL improved significantly in each group (P< 0.01 for all comparisons), but they did not find a significant correlation between the levels of the systemic inflammatory markers and the postoperative changes in BCVA, CMT and VOL (P> 0.05 for all comparisons).

Based on the results, the authors concluded that CME was significantly correlated with the elevated NLR and SII levels, which may indicate a higher incidence of CME in these patients.

Reference

1. Liao W, Liu F, Liu W, et al. Level of serum inflammation biomarkers in cystoid and diffuse diabetic macular edema. Int Ophthalmol. 2024;44:447;