Improving the Prediction of Hypertensive Target Organ Damage Using Novel Markers
Lessons From Retinal Vascular Imaging Research
See related article, pp 338–346
Retinal arteriolar narrowing is a classic sign of hypertensive retinopathy and has long been known to be a marker of hypertensive target organ damage (TOD), such as stroke, heart failure, and chronic kidney disease.1 However, despite the acceptance of the importance of this sign in the medical literature, the value of a retinal assessment in patients with hypertension remains unclear and continues to be debated in clinical guidelines.2
In this issue of the journal, Baumann et al3 examined whether the combination of retinal arteriolar narrowing and albuminuria as markers of microvascular disease may predict the progression of chronic kidney disease. The study prospectively recruited 164 men and women with early and intermediate chronic kidney disease (stages 2–4) who had retinal photographs and computer-assisted retinal vessel diameter measurement, and an assessment of albuminuria. After a median follow-up of ≈4 years, persons with retinal arteriolar narrowing had a higher risk of renal end points, defined in the study as 50% renal function loss and start of renal replacement therapy, than those without retinal arteriolar narrowing. Persons with albuminuria similarly had a higher risk of renal end points than those without albuminuria. Importantly, persons with both markers of microvascular damage (ie, retinal arteriolar narrowing and albuminuria) had substantially higher risk of renal end points compared with those who had no evidence of microvascular damage (ie, wider retinal arterioles and no albuminuria). These are new and exciting results with potential for clinical translation.
One of the long-standing hurdles in the translation of retinal vascular imaging research is the accurate documentation and measurement of retinal arteriolar narrowing. Traditionally, this clinical sign is difficult to detect even for experienced ophthalmologists. Significant improvements in digital retinal vascular imaging technologies now allow more objective documentation …