Modifiable lifestyle and environmental risk factors affecting the retinal microcirculation.

Structural changes within the human retinal vasculature may reflect systemic vascular changes associated with various cardiovascular and metabolic disorders. Recent data suggest that systemic exposure from a range of modifiable lifestyle and environmental risk factors (e.g., diet, physical activity, and smoking) may affect the morphology of the retinal vasculature. Being easily accessible and non-invasively visualized, the retinal microvasculature therefore can be a clinically useful biomarker of reversible sub-clinical physiologic deviation of the systemic circulation as results of such unfavorable exposures. Importantly, quantitative analysis of the retinal microvasculature may be utilized as a prognostic tool, allowing for targeted vascular therapies before the onset of overt cardiovascular and metabolic disorders. This review summarizes the modifiable lifestyle and environmental risk factors that affect retinal microvascular structure and the possible clinical implications of such relationships.