Retinal Vessel Caliber And Risk Of Hypertension: A Systematic Review And Individual-participant Meta-analysis

Abstract

Purpose: : Retinal vessel caliber may be a novel biomarker of hypertension risk. The aim of this systematic review was to determine if retinal vessel caliber predicts hypertension and provides information on the risk of hypertension independently of traditional risk factors.

Methods: : Relevant studies were identified through a search of MEDLINE (1950 to July 2011) and EMBASE (1950 to July 2011), a review of reference lists, and correspondence with experts. Studies were included if participants were derived from a general population, retinal vessel caliber was measured from photographs at baseline, and individuals were followed up to ascertain incident hypertension. Prespecified data on individuals in each selected study were extracted into a combined data set, and individual participant meta-analysis was conducted on individuals who had no previous history of hypertension.

Results: : Five population-based prospective cohort studies fulfilling the inclusion criteria were included. Among 10476 participants who were followed for 3 to 10 years, 1928 (18.4%) developed hypertension. Narrower retinal arterioles (pooled multivariate-adjusted hazard ratio, 1.13 [95%CI, 1.07, 1.19] per 20-µm decrease in arteriolar caliber) and wider retinal venules (1.10 [95%CI, 1.03, 1.17] per 20-µm increase in venular caliber) predicted hypertension. Inclusion of retinal vascular caliber in hypertension risk stratification using traditional risk factors (age, sex, systolic blood pressure, plasma total cholesterol level, fasting glucose, body mass index and current smoking) showed a net reclassification improvement of 3.3%.

Conclusions: : Retinal vessel caliber is independently associated with an increased risk for hypertension.

Keywords: imaging/image analysis: clinical • retina