The ocular surface and diabetes, the other 21st Century epidemic

Diabetes Mellitus (DM) is a chronic metabolic disorder characterized by sustained hyperglycemia, potentially leading to life-threatening health problems. While the complication of diabetic retinopathy has been extensively studied, less attention has been given to the impact of diabetes on ocular surface health. In fact diabetic keratopathy is potentially sight-threatening and may also provide diagnostic and management cues for other diabetic systemic complications. In this review, we provide an overview of the recent understanding of diabetic ocular surface disease, including neuropathy, dry eye, and other morphological changes of the cornea. Additionally, we will touch on several areas that have been covered less in published literature. This includes ocular surface complications in pre-diabetic states and differences in ocular surface disease between human diabetics and animal models of diabetes. Recent advances in experimental models of diabetic ocular surface complications are highlighted. The latest methods for diagnosis, management, and monitoring of DM-related ocular surface disease are also evaluated. Specifically, the advantages and limitations of cornea in vivo confocal microscopy, as well as its accessibility and potential alternatives are discussed. Additionally, future directions for research are described based on findings with promising clinical value. This includes the emergence of protein microarray technology that may be potentially applied to the diagnosis and management of diabetic ocular surface disease.