Impact of cardiometabolic factors on retinal vasculature: A 3 × 3, 6 × 6 and 8 × 8‐mm ocular coherence tomography angiography study

Abstract Background Ocular coherence tomography angiography (OCTA) is available in varying size and resolution. We sought to characterise associations of cardiometabolic factors with retinal microvascular changes using 3 × 3, 6 × 6 and 8 × 8‐mm OCTA scans to determine differences in detection with varying scan size. Methods Cross‐sectional study of 247 cardiovascular patients from a single‐centre tertiary‐care hospital. Demographic, comorbidity and medication data were obtained. Patients underwent 3 × 3, 6 × 6 and 8 × 8‐mm macula OCTA scanning using Carl Zeiss CIRRUS HD‐OCT Model 5000. Angioplex and AngioTool software was used to quantify vascular parameters in the superficial capillary plexus. Results Increasing age, hypertension, dyslipidaemia, diabetes, chronic kidney disease, coronary artery disease and peripheral vascular disease were associated with reductions in vessel density, vessel perfusion, average vessel length and/or junction density in 3 × 3‐mm OCTA ( P < .05 for all). Conversely, smoking was associated with increased vessel density, vessel length and junction density in 3 × 3‐mm OCTA ( P < .05 for all). Associations of vessel abnormalities with cardiometabolic factors were progressively weakened and statistically attenuated in 6 × 6 and 8 × 8‐mm OCTA scans. In multivariate analyses, dyslipidaemia remained an independent predictor of reduced vessel density, average vessel length and junction density ( P < .05). Conclusions Cardiometabolic factors are associated with multiple retinal microvascular changes in 3 × 3‐mm OCTA scans. These associations were weakened and progressively attenuated in OCTA scans of larger 6 × 6 and 8 × 8‐mm size. These findings advance our understanding of microcirculatory dysfunction and may have future implications for the screening and management of patients with cardiometabolic risk factors. Additional studies are required to further investigate these important associations.