Limited clinical relevance of systemic inflammatory indices in idiopathic epiretinal membrane: a retrospective case-control study.

BACKGROUND

Idiopathic epiretinal membrane (iERM) is a common age-related vitreoretinal disorder characterized by fibrocellular proliferation on the inner limiting membrane. Although systemic inflammation has been suggested to play a potential role, the diagnostic value of systemic inflammatory indices such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) remains unclear. This study aimed to evaluate whether the relationships of iERM with clinical and hematological parameters, including age, gender, systemic inflammatory indices and common comorbidities, provide clinically significant additional information.

METHODS

This retrospective case–control study included 59 patients with iERM and 56 healthy control subjects. The NLR, PLR, SII were compared between groups. Multivariable logistic regression analyses were performed to identify independent associations with iERM, and receiver operating characteristic (ROC) analyses were used to assess the discriminative performance of systemic inflammatory indices. An additional age-matched sensitivity analysis was conducted to address potential age-related confounding.

RESULTS

Patients with iERM were significantly older than controls (p < 0.001). NLR, PLR, SII, neutrophil, lymphocyte, and platelet values showed no significant difference between groups (all p > 0.05). These findings remained consistent in the age-matched sensitivity analysis, in which 36 patients with iERM were matched to 36 controls, demonstrating no significant differences in systemic inflammatory indices or hematologic parameters between matched groups (all p > 0.05). Comorbidities such as diabetes mellitus and hypertension were not independently associated with iERM (p = 0.918). In multivariable logistic regression models, age remained the only independent predictor of iERM (Model-0: AUC = 0.723). The inclusion of NLR, PLR, or SII did not significantly improve model performance (AUC < 0.02, higher AIC/BIC, lower HL-p). ROC analyses demonstrated low discriminatory ability (NLR: 0.567, PLR: 0.522, SII: 0.568).

CONCLUSION

Confirming the limited clinical significance of these readily available biomarkers will be important to avoid unnecessary clinical use of such markers in iERM and present findings may help guide future research toward local retinal mechanisms rather than systemic inflammatory biomarkers.