Aqueous Humor Cytokine Levels in Diabetic Macular Edema Patients with Cotton-Wool Spots

PURPOSE: To determine the characteristics of diabetic macular edema (DME) patients with cotton-wool spots (CWS). METHODS: We classified 80 treatment-naïve DME patients according to whether or not they had CWS involving macula and then compared the concentrations of interleukin- (IL-) 1β, IL-6, IL-8, IL-10, IL-17, placental growth factor, vascular endothelial growth factor (VEGF), and intercellular adhesion molecule (ICAM)-1 in the aqueous humor between the groups, as well as optical coherence tomography (OCT) findings, baseline characteristics, and intravitreal bevacizumab responsiveness. RESULTS: Aqueous levels of ICAM-1 and VEGF in the group with CWS were significantly higher than those in the non-CWS (control) group (p < 0.001 and p = 0.006, respectively). In multiple logistic regression analysis to identify factors associated with CWS, the aqueous ICAM-1 (≥0.36 ng/mL) was significantly associated with CWS (odds ratio = 13.26, p < 0.001). Based on OCT, ellipsoid zone (EZ) disruption distribution was significantly different between the two groups (p = 0.038). Regarding responsiveness to treatment, although there was no significant difference in central subfield thickness between the two groups after treatments, the best-corrected visual acuity was worse in the group with CWS. CONCLUSIONS: The presence of CWS was accompanied by higher levels of aqueous ICAM-1. Based on OCT, EZ disruption was greater in DME patients with CWS, and their short-term visual prognosis was poorer.