The Role of Systemic Inflammation in Age-Related Macular Degeneration Subtypes: Exploring Novel Biomarkers

Background/Objectives: This study aimed to compare hematological and inflammatory markers among patients with dry and wet age-related macular degeneration (AMD) and healthy controls, and to evaluate the influence of geographic atrophy (GA) in dry AMD and treatment response (TR) in wet AMD on these markers. Methods: The study included patients with dry AMD (n = 54), wet AMD (n = 53), and age- and sex-matched controls (n = 55). Hematological parameters, serum albumin, and systemic inflammatory indices, including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), pan-immune-inflammation value (PIV), and hemoglobin, albumin, lymphocyte, and platelet index (HALP), were compared among the groups. Results: Age and sex distributions did not differ significantly between groups. Compared to controls, the wet AMD group had significantly higher neutrophil counts (p = 0.013), red cell distribution width (RDW) (p = 0.033), and inflammatory indices, including NLR, PLR, SII, SIRI, and PIV (all p < 0.01). HALP levels were significantly lower in wet AMD (p < 0.001). Dry AMD patients also had higher PLR (p = 0.045) and RDW (p = 0.005) than controls. When comparing wet and dry AMD groups directly, SIRI (p = 0.041) and PIV (p = 0.029) were significantly elevated in wet AMD, indicating stronger systemic inflammatory burden. In the dry AMD subgroup, patients with GA had significantly lower hemoglobin (p = 0.002) and erythrocyte counts (p = 0.039) than those without GA. No significant differences were observed between TR-positive and TR-negative wet AMD patients. Conclusions: Patients with wet AMD exhibit a more pronounced systemic inflammatory profile than both dry AMD patients and healthy controls. These findings support the hypothesis that systemic inflammation may contribute to AMD pathogenesis. Geographic atrophy in dry AMD may also be associated with additional hematologic alterations, whereas treatment response in wet AMD is not reflected in systemic markers.