Therefore, it is unsurprising that evidence of microvascular dysfunction often predates evidence of clinically recognized target organ damage. The retinal microcirculation is a site where this important predictive role is recognized and, at least in those with diabetes, clinically exploited. The epidemiology of retinopathy is reviewed in detail within this edition [52] and therefore will not be covered in great detail here, except its key position

in establishing the importance of microcirculation as an early predictor of disease. The retina is a unique site where the microcirculation can be imaged directly, Selleck Pifithrin�� providing an opportunity to study in vivo the structure and pathology of the human circulation, and the possibility of detecting changes in microvasculature relating to the development of cardiovascular

disease. Diabetic retinopathy is the biggest cause of premature blindness in Western society as well as being a strong risk marker for cardiovascular mortality [33,61], hence the establishment of the annual screening program for individuals with diabetes [3,30]. The presence of retinopathy, however, may predate the occurrence of type 2 diabetes, suggesting that the diabetic phenotype may have a microvascular etiology [70]. This is consistent with reports Selleck R788 that skin microcirculatory abnormalities also predate new future diabetes [28]. In the nondiabetic population, retinopathy also carries an important prognostic role. The microvasculature of the eye is often regarded as an extension of the cerebral circulation. Therefore, its predictive role of future stroke is unsurprising, although the almost fivefold increased risk is greater than many commentators would expect. The Atherosclerosis Risk In Communities study looked prospectively at a population-based cohort for risk factors associated with future cardiovascular events [69]. The two

measures of microvascular damage assessed, retinopathy and cerebral 3-oxoacyl-(acyl-carrier-protein) reductase white matter lesions detected on MRI, were commonly associated with each other. Volunteers with evidence of retinopathy had a 4.9-fold (95% CI: 2.0–11.9) increased risk of future strokes after adjustment for age, gender, ethnicity, and vascular risk factors. Cerebral white matter lesions carried an adjusted hazard ratio of 3.4 (1.5–7.7); however, if both were present, the adjusted hazard ratio for future strokes was 18.9 (5.9–55.4), suggesting a compound effect of microvascular damage on the cerebral circulation. A similar predictive role of retinopathy in the risk of future congestive heart failure has been described [71]. Over seven years, retinopathy is associated with a twofold increased risk of congestive heart failure (HR: 1.96; 95% CI: 1.