Abstract
Purpose :
To evaluate racial differences and ocular and systemic determinants of macular thickness (MT) including central subfield macular thickness (CSMT), measured using spectral-domain optical coherence tomography (SD-OCT) in healthy eyes of 50 years and older adults.
Methods :
Data from three similarly designed population-based studies of Latinos, Chinese Americans (CAs) and African Americans (AAs) were pooled. Participants underwent a standardized interview and a comprehensive ophthalmic examination, including macular cube 512×128 scan using Cirrus SD-OCT. MT measurements were evaluated according to the ETDRS grid. Age- and race-specific measurements of MT were presented. Multivariate linear mixed regression analysis was used to evaluate the associations between MT and potential determinants with adjustments for correlations between eye-specific measurements from the same person.
Results :
Macular scans from healthy eyes of 6942 individuals (1811 AAs, 2949 CAs, and 2182 Latinos) were pooled. AAs had thinner MT in central, all inner and outer macular regions than CAs and Latinos after adjusting for age. MT was similar between CAs and Latinos in all macular regions except CSMT. The average CSMT was thinnest in AAs (mean ± standard deviation, 244.1 ± 26.6 μm), followed by CAs (248.5 ± 22.6 μm) and Latinos, (253.0 ± 25.7 μm) (P for pair-wise comparisons<0.05). These differences remained significant after adjusting for other associated factors and for multiple testing. Older age, longer axial length, and female sex were consistently associated with thinner average MT in all racial/ethnic groups; however, the spatial pattern of age-related MT loss differed between the three racial/ethnic groups. Longer axial length and female sex were also associated with thinner CSMT in all three racial/ethnic groups; however, their effect sizes varied by race/ethnicity with a greater effect of axial length observed in CAs (3.0 μm thinner per each mm longer in axial length) than AAs (1.5 μm) and Latinos (1.0 μm) and greater effect of female sex in Latinos (15.5 μm thinner) than AAs (11.7 μm) and CAs (10.1 μm).
Conclusions :
There are important racial/ethnic differences in MT and CSMT among minority Americans. Race/ethnic-specific information needs to be considered in the clinical interpretation of macular OCT scans to improve the screening and diagnostic accuracy of macular diseases in minority Americans.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.