The role of blood related inflammatory factors on age-related macular degeneration (AMD)

Abstract

Age-related macular degeneration (AMD) is a significant retinal disease that leads to irreversible low vision, particularly in developing countries. The variation in AMD prevalence among different racial groups and highlighted role of inflammation on disease pathology from previous studies which yielded in inconsistent findings, It seems to be of great importance to do more investigation in this field. This case control study involved 204 participants, divided into four groups of equal size (51 individuals per group). Three groups represented AMD cases of varying severity according to Beckman classification (3 groups) and one healthy control group. Sampling was conducted exhaustively until the desired sample size was reached. The control group comprised healthy individuals without any infectious or inflammatory systemic, ophthalmic disease. Blood samples were collected to measure inflammatory factors, including lymphocytes, monocytes, neutrophils, neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein (CRP). Collected data were analyzed by statistical methods in SPSS version 21. Of the participants, 51% were women, and their ages ranged from 47 to 89 years (62.2 ± 8). According to multiple logistic regression analysis, age exhibited a statistically significant positive association with AMD severity (P = 0.038, odds ratio [OR] = 1.034). ANOVA results indicated a significant association between neutrophil count and AMD severity (P < 0.001). As the disease severity increased, the number of neutrophils decreased. The mean ± SD neutrophil counts for early, intermediate and advanced AMD were 3849 ± 800, 3702 ± 734, and 3342 ± 823, respectively. No statistically significant associations were found between lymphocyte count, monocyte count, neutrophil-to-lymphocyte ratio, CRP, and AMD. There was a significant relationship between the number of neutrophils in peripheral blood and the severity of AMD in study participants which needs more evaluation for the potential utility of this factor in the prognosis of AMD. There was not any significant relationship among the other factors and AMD.