OBJECTIVE: To find an objective, sensitive method for quantifying microvascular alterations associated with level of blood pressure and age. DESIGN: A prospective cross-sectional study. SUBJECTS AND METHODS: Seventy-four previously untreated hypertensive patients, referred to a hospital outpatients department, and 26 normotensive volunteers participated. Twenty-four-hour ambulatory blood pressure monitoring and bilateral fundal photography were performed. The fundal photographs were projected on a screen such that the optic disc filled a circle of radius 5 cm. Microvessels crossing the border of a concentric circle of radius 20 cm were identified as arteriolar or venular, counted and their luminal diameters measured. MAIN OUTCOME MEASURES: Arteriolar and venular numbers, mean diameters and vascularities (arteriolar and venular vascularities defined as the sum of arteriolar and venular diameters, respectively). RESULTS: The technique was reproducible. As blood pressure increased, arteriolar vascularity declined and venular vascularity increased. These associations resulted in a strong inverse correlation between blood pressure level and the ratio arteriolar vascularity: venular vascularity (r = 0.48, P < 0.001). Arteriolar number declined with increasing diastolic blood pressure (r = 0.22, P < 0.05). Mean arteriolar diameter appeared to have a U-shaped relationship with diastolic blood pressure levels (r = 0.27, P < 0.05). Venular dilation was associated with increasing blood pressure levels (r = 0.22, P < 0.05). Mean arteriolar and venular diameters declined significantly with age (r = 0.33 and 0.26, respectively; P < 0.01) and there was no association between arteriolar vascularity:venular vascularity ratio and age. CONCLUSIONS: The method detected disparate retinal microvascular alterations with age and blood pressure. The arteriolar vascularity:venular vascularity ratio shows promise as a non-invasive, prognostic and therapeutic guide in hypertension.
OBJECTIVE: To find an objective, sensitive method for quantifying microvascular alterations associated with level of blood pressure and age. DESIGN: A prospective cross-sectional study. SUBJECTS AND METHODS: Seventy-four previously untreated hypertensivepatients, referred to a hospital outpatients department, and 26 normotensive volunteers participated. Twenty-four-hour ambulatory blood pressure monitoring and bilateral fundal photography were performed. The fundal photographs were projected on a screen such that the optic disc filled a circle of radius 5 cm. Microvessels crossing the border of a concentric circle of radius 20 cm were identified as arteriolar or venular, counted and their luminal diameters measured. MAIN OUTCOME MEASURES: Arteriolar and venular numbers, mean diameters and vascularities (arteriolar and venular vascularities defined as the sum of arteriolar and venular diameters, respectively). RESULTS: The technique was reproducible. As blood pressure increased, arteriolar vascularity declined and venular vascularity increased. These associations resulted in a strong inverse correlation between blood pressure level and the ratio arteriolar vascularity: venular vascularity (r = 0.48, P < 0.001). Arteriolar number declined with increasing diastolic blood pressure (r = 0.22, P < 0.05). Mean arteriolar diameter appeared to have a U-shaped relationship with diastolic blood pressure levels (r = 0.27, P < 0.05). Venular dilation was associated with increasing blood pressure levels (r = 0.22, P < 0.05). Mean arteriolar and venular diameters declined significantly with age (r = 0.33 and 0.26, respectively; P < 0.01) and there was no association between arteriolar vascularity:venular vascularity ratio and age. CONCLUSIONS: The method detected disparate retinal microvascular alterations with age and blood pressure. The arteriolar vascularity:venular vascularity ratio shows promise as a non-invasive, prognostic and therapeutic guide in hypertension.
Authors: Andréa Vasconcellos Batista da Silva; Sonia Alves Gouvea; Aurélio Paulo Batista da Silva; Saulo Bortolon; Anabel Nunes Rodrigues; Glaucia Rodrigues Abreu; Fernando Luiz Herkenhoff Journal: Int J Gen Med Date: 2015-08-25