Purpose: To determine possible correlations between different levels of blood pressure (BP) control and retinal microvascular changes in the macula and optic nerve head, using coherence tomography angiography (OCTA) in hypertensive patients without hypertensive retinopathy.
Methods: This was an observational, cross-sectional study. Seventy-three patients and 40 healthy volunteers were included in this study. The patients and volunteers were divided into four groups and from each participant one eye was selected randomly: Group A comprised 32 hypertensive patients with intensive BP control; Group B comprised 26 hypertensive patients with standard BP control; Group C comprised 15 hypertensive patients with poor BP control; Group D comprised 40 control subjects. 6 × 6 mm macula scan and 4.5 × 4.5 mm optic nerve head scan were obtained using OCTA.
Results: In macula scans, most measured regions of retinal VD showed significant reduction in group C, compared to groups A, B, and D (all P < .05). Partial measured regions of retinal VD were significantly lower in group B than groups A and D (all P < .05). In ONH scans, RNFL thickness and inside disc capillary density were significantly thinner and lower in groups B and C than in group D (all P < .05). SBP was significantly correlated with RNFL thickness (R = 0.430, 95% CI -0.583 to -0.201, P ≤ 0.001).
Conclusions: We demonstrated that the frequency of OCTA follow-up may improve detection of reduced retinal VD, thus avoiding further retinal damage in hypertensive patients; however, the clinical implications of this finding deserve further study. Moreover, further exploration is needed regarding the implication that reduced SBP may be beneficial for lowering the risk of glaucoma.
Keywords: Vessel density; hypertension; intensive Blood Pressure Control; poor Blood Pressure Control; retinal Nerve Fiber Layer Thickness; standard Blood Pressure Control.