To study the associations of subfoveal choroidal thickness with vascular risk factors and age-related macular degeneration.
Two hundred sixty-one participants of the Alienor study had gradable enhanced-depth imaging optical coherence tomography scans of the macula and available data on vascular and genetic risk factors (assessed through face-to-face interview and fasting blood samples) and age-related macular degeneration status (assessed from retinal photographs and optical coherence tomography). Subfoveal choroidal thickness was measured manually on one horizontal scan passing through the fovea.
In a multivariate mixed linear model, subfoveal choroidal thickness was independently associated with age greater than 80 years (−21.77 μm, P = 0.02), axial length (−21.77 μm, P < 0.0001), heavy smoking (≥20 pack-years: −24.89 μm, P = 0.05), fasting blood glucose higher than 7 mmol/L (−53.17 μm, P = 0.02), and lipid-lowering treatment (+18.23, P = 0.047). After multivariate adjustment for age, sex, axial length, and vascular and genetic risk factors, subfoveal choroidal thickness was thinner in eyes with central hyperpigmentation (−45.39 μm, P = 0.006), central hypopigmentation (−44.99 μm, P = 0.001), and central pigmentary abnormalities (−44.50 μm, P = 0.001), but not in eyes with late age-related macular degeneration (−18.05 μm, P = 0.33) or soft drusen.
These findings indicate a relationship between vascular risk factors and choroidal thinning and suggest an early involvement of the choroid in the pathogenesis of age-related macular degeneration.