Intensive SBP treatment improves retinal microvasculature in hypertensive patients

Lowering the systolic blood pressure (SBP) target to <120 mm Hg compared with <140 mm Hg has a beneficial effect on retinal microvasculature among hypertensive patients with high cardiovascular risk, suggests a recent study.

This finding provides evidence that such intervention may improve systemic microcirculation and prevent hypertension-mediated organ damage.

A multicentre randomized trial was conducted across 116 sites in China. Adults aged ≥50 years with high cardiovascular risk were randomized to receive intensive (<120 mm Hg) or standard SBP treatment (<140 mm Hg). A subgroup at 17 sites underwent colour fundus photography at a 3-year follow-up.

The researchers derived retinal microvasculature measures via a standard pipeline. The main outcome was arteriole-venule ratio, a measure of retinal arteriolar caliber, and other measures included vessel complexity, density, and tortuosity. Subgroup analyses were conducted for arteriole-venule ratio.

Of the participants (mean age 62.7 years, 37.8 percent women), 555 were assigned to the intensive arm and 526 to the standard arm.

Compared with the standard arm, the intensive arm showed increased arteriolar caliber after adjustments for age and sex, as seen in the arteriole-venule ratio (β, 0.16, 95 percent confidence interval [CI], 0.05–0.28; p=0.005), consistent with central retinal arteriole equivalent (β, 0.14, 95 percent CI, 0.02–0.25; p=0.02).

Results for venular caliber did not reach significance, and no heterogeneity was noted across subgroups.

Furthermore, participants in the intensive arm had increased arteriolar complexity, arteriolar density, and reduced vessel tortuosity than those in the standard arm.

“Retinal microvasculature is a key affected target organ of hypertension, which can serve as a marker of systemic microcirculation,” the researchers said.