RETN and non-proliferative diabetic retinopathy: In sub-group analysis of DR, adiponectin, leptin, resistin, TNF-α, Factor D (adipsin), CCL2 (MCP-1), lipocalin-2(NGAL), Serpin E1 (PAI-1), IL-1β, and CXCL8 (IL-8) in severe NPDR were significantly positively correlated with WC.