Two-Year Choroidal Thickness Attenuation and Its Associations in Healthy Chinese Adults

Identifying clinical associations causing attenuation in choroidal thickness (CT) among healthy Chinese adults.

A 2-year longitudinal study was conducted in volunteers aged over 30 years from China. All participants had no history of eye disease or surgery. All subjects underwent swept-source optical coherence tomography to measure the CT in the macular region at baseline and at 2-year follow-up. The regression models were based on the generalized estimating equation.

A total of 603 eyes of 336 healthy participants were included in the final analysis (mean [SD] age, 58.88 [8.82] years; 74.70% female). Mean (SD) choroidal thickness (MCT) was reduced significantly from 206.62 (72.42) to 194.02 (72.08) µm (difference, -12.60 µm; 95% confidence interval [CI], -13.62 to -11.57). Among the Early Treatment of Diabetic Retinopathy Study (ETDRS) grid, CT at the subfoveal sector showed the greatest 2-year reduction (difference, -14.55 µm; 95% CI, -15.87 to -13.22). The largest 2-year change was observed in the 50 to 59 years group (difference, -14.51 µm; 95% CI, -16.71 to -12.32). Multivariate regression showed female gender (β = -2.85; 95% CI, -5.65 to -0.56) and baseline MCT (β = -0.040; 95% CI, -0.056 to -0.024) were significantly and independently associated with greater 2-year CT decrease.

These results indicated that CT among Chinese healthy adults decreased during the 2-year follow-up, and the greater choroidal thinning rate was significantly associated with female gender and larger baseline MCT.

Longitudinal CT data of healthy adults provide a reference range when evaluating pathologic variations, especially for the age-related retinal-choroidal disorders.