Clinical Practice GuidelinesRetinopathy
Introduction
Diabetic retinopathy is the most common cause of new cases of legal blindness in people of working age (1). The Eye Diseases Prevalence Research Group determined the crude prevalence rate of retinopathy in the adult population with diabetes of the United States to be 40.3%; sight-threatening retinopathy occurred at a rate of 8.2% (1). Previous data showed the prevalence rate of proliferative retinopathy to be 23% in people with type 1 diabetes, 14% in people with type 2 diabetes and on insulin therapy, and 3% in people receiving oral antihyperglycemic therapies (2). Macular edema occurs in 11%, 15% and 4% of these groups, respectively (3). Higher prevalence rates were noted in First Nations populations in Canada 4, 5.
Visual loss is associated with significant morbidity, including increased falls, hip fracture and a 4-fold increase in mortality (6). Among individuals with type 1 diabetes, limb amputation and visual loss due to diabetic retinopathy are the independent predictors of early death (7).
Section snippets
Definition and Pathogenesis
Diabetic retinopathy is clinically defined, diagnosed and treated based on the extent of retinal vascular disease exclusively. Three distinct forms of diabetic retinopathy are described: 1) macular edema, which includes diffuse or focal vascular leakage at the macula; 2) progressive accumulation of blood vessel change that includes microaneurysms, intraretinal hemorrhage, vascular tortuosity and vascular malformation (together known as nonproliferative diabetic retinopathy) that ultimately
Screening
Because laser therapy for sight-threatening diabetic retinopathy reduces the risk of blindness, ophthalmic screening strategies are intended to detect disease treatable by this modality 8, 9, 10, 11. Sight-threatening diabetic retinopathy includes severe nonproliferative diabetic retinopathy, proliferative diabetic retinopathy or clinically significant macular edema (CSME) (8), a strictly defined form of diabetic macular edema (DME) that relies on the clinical assessment of retinal thickening
Delay of Onset and Progression
Risk factors for the development or progression of diabetic retinopathy are longer duration of diabetes, elevated glycated hemoglobin (A1C), increased blood pressure (BP), dyslipidemia, low hemoglobin level, pregnancy (with type 1 diabetes), proteinuria and severe retinopathy itself 14, 15, 16, 17, 19, 25, 26, 27, 28, 29, 30, 31.
Treatment
Treatment modalities for diabetic retinopathy include retinal photocoagulation, intraocular injection of pharmacological agents and vitreoretinal surgery.
Other Relevant Guidelines
Targets for Glycemic Control, p. S31
Dyslipidemia, p. S110
Treatment of Hypertension, p. S117
Type 1 Diabetes in Children and Adolescents, p. S153
Type 2 Diabetes in Children and Adolescents, p. S163
Diabetes and Pregnancy, p. S168
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