Differences in macular capillary parameters between healthy black and white subjects with Optical Coherence Tomography Angiography (OCTA)

Abstract

PurposeTo investigate if there are differences in macular capillaries between black and white subjects using optical coherence tomography angiography (OCTA) and identify potential factors underlying the epidemiologically-based higher vulnerability of black populations to diabetic retinopathy (DR).MethodsThis prospective, observational cross-sectional study included 93 eyes of 47 healthy subjects with no medical history and ocular history who self-identified as black or white and were matched for age, sex, refractive error, and image quality. Subjects underwent OCTA imaging (RTVue-XR Avanti) of the superficial (SCP) and deep (DCP) capillary plexuses and choriocapillaris. AngioAnalytics was used to analyze vessel density (VD) and choriocapillaris % blood flow area (BFA) in the 1mm-diameter fovea, parafovea, and 3mm-diameter circular area including the fovea and parafovea (3x3mm image). Foveal avascular zone (FAZ) was also analyzed. Linear mixed models were used to evaluate for differences between the study groups.ResultsCompared to the white subjects in this study, black subjects were found to have: lower foveal VD in the SCP (p<0.05); lower VD in the parafovea and in the 3x3mm image in the DCP (p<0.05); larger FAZ in SCP and DCP (p<0.05); and decreased choriocapillary BFA in the area underlying the fovea, parafovea, and 3x3mm image (p<0.05).ConclusionIn our study, our black subjects had decreased macular capillary vasculature compared to matched white subjects, even in early adulthood and the absence of any systemic or ocular conditions. To our knowledge, this is the first report showing that retinal and choriocapillary vascular differences may contribute to racial disparities in vulnerability to DR.

Retinal microvascular abnormalities in patients after COVID-19 depending on disease severity

“…The origin or ethnicity of the participants could also influence the VD findings. Some authors described specific inter-racial differences in the central retina thickness and specifically in VDs between white and black, [16][17][18] although there are no further studies among other ethnicities. Chun et al theorise that such differences could account for a greater likelihood of diabetic retinopathy among black people, although there is no evidence for this relationship.…”

Quantitative Optical Coherence Tomography Angiography (OCTA) Parameters in a Black Diabetic Population and Correlations with Systemic Diseases

“…Prior studies have shown that age is correlated with decreased retinal capillary density in healthy subjects [ 27 , 28 , 29 , 30 ], including black populations [ 31 ]. Additionally, healthy black subjects have shown to have an increased FAZ area at baseline compared to white subjects [ 21 , 32 ], and diabetic patients have also been shown to have an increased FAZ area compared to non-diabetic patients even in the absence of diabetic retinopathy [ 13 , 15 ]. Based on this prior data, we know that black populations as well as diabetic populations have baseline structural differences in retinal microvasculature compared to subjects of other ethnicities and non-diabetics.…”

“…Differences between races on OCTA analysis have also been identified, as prior studies from our group have suggested that black populations may have decreased macular capillary vasculature at baseline compared to white populations even in the absence of systemic disease [ 21 ]. To date, limited data has been published regarding changes in retinal microvasculature in black subjects with diabetes and how these changes may correlate with systemic biomarkers.…”

Superficial capillary perfusion on optical coherence tomography angiography differentiates moderate and severe nonproliferative diabetic retinopathy

“…The moderate NPDR group had a higher proportion of African-American patients relative to the other groups, while the severe NPDR group was disproportionately Hispanic. Chun et al demonstrated that OCTA parameters may vary significantly with race in healthy subjects, with African-American patients having lower baseline DCP parafoveal VD and higher FAZ area compared to white patients [ 42 ]. While we do not know of any influence of Hispanic race on vascular parameters, larger datasets are needed to explore race as a potential confounder.…”