Systemic Inflammatory Response Index Predicts Macular Degeneration

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A recent cross-sectional analysis of National Health and Nutrition Examination Survey (NHANES) data conducted in Tianjin revealed that the systemic inflammatory response index can be used to successfully identify age-related macular degeneration (AMD).

“These findings suggest that [the index] could be used as a biomarker for AMD risk assessment, which can greatly benefit patient care,” wrote Ruoshuang Jia, department of anesthesiology, Tianjin Medical University and colleagues. “Since it is derived from peripheral blood, its measurement is straightforward, cost-effective, and non-invasive.”1

Participants were selected from NHANES data taken during 2005-2008, specifically those aged ≥ 40 years and with systemic inflammatory response index and AMD status data. Index data was calculated by dividing the product of total monocytes and neutrophils by total lymphocytes. Of the 5365 participants included in the study, 425 had AMD, which was detected through the following conditions:

• Presence of soft drusen and pigmented abnormalities
• Presence of geographic atrophy or pigment epithelial detachment
• Presence of subretinal hemorrhage or visible subretinal new vessels
• Presence of subretinal fibrous or laser treatment scars1

Subgroups established included sex, ethnicity, smoking status, and presence of hypertension, obesity, and diabetes. Although some subgroups did not show a significant association between systemic inflammatory response index and AMD, the majority did exhibit a correlation, including men (P = .043), non-smokers (P = .0009), and those with hypertension (P = .02) and obesity (P = .04).1

Systemic inflammatory response index values were organized into tertiles based on distribution of values in the study population, so that linear trends between the index and AMD could be evaluated.

Jia and colleagues measured the association between systemic inflammatory response index and AMD risk through multivariable logistic regression analysis. The median index measurement was substantially higher in patients diagnosed with AMD (1.23 vs 1.04; P <.001), and a higher index measurement was independently associated with higher odds of AMD (adjusted OR: 1.18, 95% CI, 1.07-1.29; P = .001).1

When measuring the index as a continuous variable, the team discovered a positive correlation between the index and AMD (95% CI, 1.22-1.47, P <.001), which continued after accounting for potential confounders (95% CI, 1.07-1.29; P = .001). When measured as a categorical variable, the index showed that participants in the highest index tertile had an increased risk of AMD compared to the lowest quartile (95% CI, 1.05-1.77; P = .021). Importantly, restricted cubic spline curve analysis indicated a dose-response relationship (P = .002).1

Systemic inflammatory response index has been suggested as a predictor for a variety of diseases; its association with all-cause mortality in stroke patients and its prognostic value in determining outcomes after off-pump coronary artery bypass grafting have been heavily studied.2,3 Given the complexity of AMD pathogenesis, the team believes that the systemic inflammatory response index could act as a predictor and simplify much of the multifactorial nature of anticipating the disease. However, data on the index’s relationship with AMD is lacking.

The team believes the result of this study to be promising; however, Jia and colleagues point out that, while an association between the index and AMD exists, the presence of other unmeasured factors could discount an actual causal relationship. They indicate these gaps in existing knowledge as the next required area of study.1

“To address the current knowledge gaps, further prospective studies are urgently needed,” wrote Jia and colleagues. “This in-depth understanding will be instrumental in developing more targeted and effective prevention and treatment strategies for AMD, ultimately benefiting a large number of patients worldwide.”1

References

1. Jia R, Yin Y, Shan H. Systemic inflammatory response index as a novel biomarker for age-related macular degeneration: A cross-sectional study from NHANES (2005–2008). Frontiers in Nutrition. 2025;12. doi:10.3389/fnut.2025.1540933

2. Zhang Y, Xing Z, Zhou K, Jiang S. The predictive role of systemic inflammation response index (SIRI) in the prognosis of stroke patients. Clinical Interventions in Aging. 2021;Volume 16:1997-2007. doi:10.2147/cia.s339221

3. Urbanowicz T, Olasińska-Wiśniewska A, Michalak M, et al. Pre-operative systemic inflammatory response index influences long-term survival rate in off-pump surgical revascularization. PLOS ONE. 2022;17(12). doi:10.1371/journal.pone.0276138