Plasma markers of chronic low-grade inflammation in polypoidal choroidal vasculopathy and neovascular age-related macular degeneration

PURPOSE: Ageing is the strongest predictor of neovascular age-related macular degeneration (AMD), where neuroinflammation is known to play a major role. Less is known about polypoidal choroidal vasculopathy (PCV), which is an important differential diagnosis to neovascular AMD. Here, we report plasma markers of inflammation with age (inflammaging) in patients with PCV, patients with neovascular AMD and a healthy age-matched control group.

METHODS: We isolated plasma from fresh venous blood obtained from participants (n = 90) with either PCV, neovascular AMD, or healthy maculae. Interleukin(IL)-1β, IL-6, IL-8, IL-10 and tumour necrosis factor receptor 2 (TNF-R2) were measured using U-PLEX Human Assays. Routine plasma C-reactive protein (CRP) was measured using Dimension Vista 1500.

RESULTS: Patients with PCV had plasma levels of IL-1β, IL-6, IL-8, IL-10 and TNF-R2 similar to that in healthy controls. Patients with neovascular AMD had significantly higher plasma IL-1β, IL-6 and IL-10 than healthy controls, whereas no significant differences were observed for plasma IL-8 and TNF-R2. Differences between plasma IL-1β, IL-6 and IL-10 possessed a positive but weak ability in discriminating neovascular AMD from PCV. Both patients with PCV and patients with neovascular AMD had significantly higher levels of routine plasma CRP.

CONCLUSION: Patients with PCV differ from patients with neovascular AMD in terms of plasma inflammaging profile. Apart from increased CRP, no signs of inflammaging were observed in patients with PCV. In patients with neovascular AMD, we find a specific angiogenesis-twisted inflammaging profile.