The impact of vascular risk factors on the thickness and volume of the choroid in AMD patients

Abstract

Disturbances in choroidal microcirculation may lead to the onset and progression of age-related macular degeneration (AMD). We aimed to assess changes in the choroidal volume and thickness in the macular region in AMD eyes and to investigate whether coexisting vascular risk factors alter choroidal status. We enrolled 354 AMD patients (175 dry, 179 wet AMD) and 121 healthy controls. All participants underwent a complete ophthalmologic examination and assessment of choroidal thickness and volume. A multivariate analysis adjusted for age, sex, and smoking status revealed that wet AMD was an independent factor associated with higher average thickness of the central ring area (ATC) and average volume of the central ring area (AVC) and lower choroidal vascularity index (CVI) compared to controls (β = + 0.18, p = 0.0007, β = + 0.18, p = 0.0008, respectively) and to dry AMD (β = + 0.17, p = 0.00003 for both ATC and AVC and β = - 0.30 p < 0.0001 for CVI). ATC, AVC and average volume (AV) were lower in AMD patients with hypertension and ischaemic heart disease (IHD). The duration of hypertension was inversely correlated with ATC, AVC and AV (Rs = - 0.13, p < 0.05; Rs = - 0.12; p < 0.05, Rs = - 0.12; p < 0.05, respectively) while IHD duration negatively correlated with AV (Rs = - 0.15, p < 0.05). No such associations were observed in the control group. Our findings show that the choroidal vascular system in eyes with AMD is much more susceptible to damage in the presence than in the absence of systemic vascular disease.