Factors associated with changes in retinal microcirculation after antihypertensive treatment

We report the results of hypertensive treatment over retinal arteriole narrowing in a group of 189 hypertensive patients during a 6-month treatment programme for hypertension. These patients were included in an observational study under clinical practice conditions and analysed using digital photographs of the eye fundus with a previously described semiautomatic snakes method. We analysed the relation between blood pressure control and retinal microcirculation changes during the treatment. We included 189 hypertensive patients; 74.0% of them had BP under control after 6 months of follow-up. The arteriovenous ratio (AVR), measured as the relation between the average retinal arteriole and venous diameter, significantly increased after 6 months of follow-up in both eyes (right eye AVR: 0.769 +/- 0.065 vs 0.799 +/- 0.066 (P<0.0001); left eye AVR: 0.770 +/- 0.065 vs 0.796 +/- 0.071 (P<0.0001)). AVR changes were caused by increases in arteriole diameter. No linear correlation was found between blood pressure-lowering levels and AVR increase, suggesting that other factors could be involved in the regression of retinal changes. We conclude that in our group of hypertensive patients it was possible to increase the retinal arteriole diameter, expressing an improvement in retinal microcirculation after 6 months of adequate BP control. Although there is an inverse tendency between blood pressure and arteriovenous ratio changes, we could not find a linear correlation between these changes.