Fred Hollows lecture: hypertensive retinopathy - a journey from fundoscopy to digital imaging

Hypertensive retinopathy refers to a spectrum of retinal microvascular signs that develop in response to elevated blood pressure. These signs are broadly divided into localized signs (focal retinal arteriolar narrowing, arteriovenous nicking, retinal haemorrhages, cotton wool spots, hard exudates and microaneurysms) and diffuse signs (generalized retinal arteriolar narrowing, arterial wall opacification and optic disc oedema). Although their association with systemic morbidity was recognized more than a century ago, the prognostic significance of hypertensive retinopathy has not received much attention. In large part, this is because clinical assessment of hypertensive retinopathy signs with the direct fundoscopy has proven imprecise. Data from large population-based studies in the past decade, using retinal photographic methods to define hypertensive retinopathy signs, have provided new insights into the epidemiology, systemic associations and clinical significance of hypertensive retinopathy. These studies show that hypertensive retinopathy signs are common (up to 14% of adults aged 40 years and older, even in those without clinical diabetes or hypertension) and are strongly associated with blood pressure. Various retinopathy signs predict the risk of stroke, congestive heart failure and cardiovascular mortality, independent of blood pressure and other risk factors. These data suggest that patients with hypertensive retinopathy signs may benefit from a careful cardiovascular evaluation, and appropriate risk reduction therapy if indicated. Future advances in digital retinal imaging technology will allow researchers and clinicians to better chart and monitor the vascular effects of hypertension.