Retinal vascular signs as risk markers for incident stroke or cerebrovascular death: A population-based assessment

点击翻译按钮获取中文摘要

Stroke remains a major cause of disability and death in Australia. Preliminary data from the Blue Mountains Eye Study suggest that blood vessel changes observed in the retina at the back of the eye may provide signs of an increased risk of stroke or death from stroke. Importantly, although stroke is strongly associated with elevated blood pressure, the risk associated with these blood vessel signs seems to be independent of blood pressure. The proposed study will conduct a detailed re-grading of retinal photographs taken on people who attended the Eye Study during 1992-4 and 5-year follow-up exams during 1997-9. We will grade these photographs manually (using a stereo-viewer), and with computer assistance to measure changes in the diameter of small arteries in the retina and other signs. By closely matching our grading technique to that used in a large American Study, we hope to develop reliable grading for these signs and will be able to compare our findings internationally. Our aim is to assess the frequency of abnormal retinal vessel changes in people of different age groups as well as the development and progression of these signs over time. Their relationship to well known vascular risk factors like smoking, blood pressure, obesity, diabetes and cholesterol will also be investigated. We hope to be able to discriminate those changes associated with an increased stroke risk from those due to normal ageing. We expect that the increased stroke risk associated with abnormal retinal vessel changes may be greater than shown in our early data. If confirmed, then these findings may provide a more sensitive and objective measure of stroke risk than relying on traditional risk factors, which are difficult to quantify and change with time. We may be able to develop simple rules so that doctors using an ophthalmoscope or examining a retinal photograph could identify high risk patients. These people could benefit from interventions to reduce their risk.