Chronic Renal Insufficiency (CRI) has been recognized as a silent epidemic affecting more than 10 million Americans. To gain understanding of the relationship between progressive renal disease and cardiovascular illness, the National Institute of Diabetes, Digestive, and Kidney Diseases (NIDDK) established the Chronic Renal Insufficiency Cohort (CRIC) Study in 2001. The principal goals of the CRIC Study are to examine risk factors for CRI and CVD events among patients with varying severity of CRI, and develop predictive models that will identify high-risk subgroups with CRI. The CRIC study did not include an eye component as part of the overall assessment of the patients. Recent studies, however, have suggested that retinal vascular abnormalities due to diabetic and hypertensive retinopathy are representative of the microvascular pathology that affects other organs such as the kidney and the heart. The presence of such retinal vascular abnormalities is associated with a markedly increased risk of progression of renal and cardiovascular disease, among others. To gain information about eye pathology in the CRIC population we obtained a set of baseline fundus photographs in 1890 CRIC subjects. The purpose of this follow up ancillary study will be to obtain 3-year follow up fundus photographs on CRIC patients that have gradable baseline photographs, to investigate the relationship between progression of retinopathy and progression of CRI and CVD. Potentially, non-invasive fundus photography could provide unique information about the microvasculature that would not be available through any other means. Such information could identify new risk factors that would significantly improve the predictive models to be developed through the CRIC study. Additionally, because many of the CRIC study participants are at high risk of developing significant morbidity from retinopathy due to diabetes mellitus, systemic hypertension and other vascular diseases, it is important to assess the ocular condition of patients with CRI to gain a more comprehensive evaluation of the overall pathology caused by CRI. This grant offers a unique opportunity to merge information on the ocular condition of CRIC patients with the vast amount of data that will be collected by the CRIC study, an endeavor that will yield important insight into the relationship between retinopathy and CRI.
We are currently performing a study funded by the NIDDK in which photographs have been obtained at baseline in patients with kidney disease that are participating in the Chronic Renal Insufficiency Cohort (CRIC) study. In this current Supplemental or Revised application, we are proposing to obtain additional 3-year follow up eye photography in patients in which we have previously obtained baseline photos. This will allow us to investigate the relationship between progression of retinopathy and progression of kidney and cardiac disease. Because the pathologic changes that occur in the blood vessels in the back of the eye probably represent vascular changes that occur in the rest of the body, the data obtained through non-invasive photography may provide important information of prognostic value regarding the progression of kidney and heart disease.
