Epidemiologic Study of Diabetic Retinopathy. Klein demonstrated a reduction in incidence of PDR in more recently diagnosed cohorts. (Level 2) In 2009, Wong64 conducted a systematic review of rates of progression in diabetic retinopathy during different time periods. The authors concluded that since 1985, lower rates of progression to PDR and severe visual loss (SVL) were being reported by the studies included in the review. These findings may reflect an increased awareness of retinopathy risk factors; earlier identification and initiation of care for patients with retinopathy; and improved medical management of glucose, blood pressure, and serum lipids. (Level 1) In 2010, Varma65 demonstrated that the 4-year incidence and progression of DR and the incidence of clinically significant macular oedema (CSMO) are high among Latinos compared to non-Hispanic whites. (Level 2) The incidence and progression of DR can be seen to be related to a variety of risk factors and these are considered further in Section 6. 2.4.3 Incidence and prevalence of cataract in people with diabetes In 1995, Klein66 reported the occurrence of cataract surgery in people in the WESDR study. In the younger-onset group there was an 8.3% (95% confidence interval, 6.2%, 10.8%) cumulative incidence, and in the older-onset group there was a 24.9% (95% confidence interval, 21.3%, 28.5%) cumulative incidence of cataract surgery in the ten-year interval. Statistically significant characteristics related to cataract surgery in the younger-onset group in multivariate analysis were age, severity of diabetic retinopathy, and proteinuria. In the older-onset group, age and use of insulin were associated with increased risk. (Level 1) Studies by Henricsson67 , Chew68 , Mittra69 , Chung70 , Somaiya71 and Liao72 have shown an increased risk of ocular complications in diabetics after cataract surgery but the same studies and those by Dowler73 , Flesner74 , Squirrell75 and Hauser76 have shown that modern surgical techniques have minimised risks. Macular oedema before surgery is the most common condition that limits post-operative visual recovery68 70 73 . Thus, pre-operative and or perioperative management of DMO needs careful planning. (See Sections 11 and 1 Referral into Secondary Care When a PWLD requires assessment at a hospital, either because of difficulties with local screening or because of a positive screen, it should be clearly stated on the referral that the patient has learning difficulties so that pre-appointment information and/or visits can be facilitated. 33 5) Consent Capacity to consent is procedure-specific. Clinicians should judge, in conjunction with carers, if the patient is able to consent to each procedure. For example a patient may be able to consent to eye drops and fundus examination or photography, but not to laser treatment. Concerns about consent should not be a barrier to screening or treatment. 6) Communication Information about screening and treatment of diabetic eye disease should be provided in a format which is accessible by the patient. It is advisable to provide EasyRead leaflets which will help people with learning disability understand and prepare for eye examinations and clinic visits1,2 . PWLD often have multiple care providers. Medical and personal information is held in a personal care plan. In addition to communicating with the GP it is important to include feedback about managing diabetic eye disease within the care plan. For example, the importance of blood glucose and blood pressure control should be shared with the whole care team, not just the carer attending clinic. 7) Did Not Attend Policies People with learning disability are “vulnerable patients” and should be exempt from DNA policies for missed appointments. 8) Visual Impairment Registration People with learning disabilities can benefit from low vision services: an inability to read should not preclude registration for visual impirement (=Ophthalmic+Services+ Gu idance . 34 SECTION 5: THE PUBLIC HEALTH ASPECTS OF DIABETIC RETINOPATHY 5.1 INTRODUCTION Public health is described as the “The science and art of promoting and protecting health and well-being, preventing ill-health and prolonging life through the organised efforts of society” As such, public health brings a population perspective to our understanding of a condition. There are two aspects to this, firstly, public health (PH) practitioners consider the impact of a condition in a population rather than an individual; secondly, they develop and implement interventions for populations to improve outcomes. In the case of diabetic retinopathy (DR), the population analysis of the condition includes an understanding of: · The epidemiology of diabetes · The epidemiology of DR · The burden of disease from DR · Socio-economic aspects of the condition · The economic impact of the condition and its treatment These factors are important in developing public health interventions that use resources effectively to deliver improved outcomes at a population level. These interventions include prevention of diabetes through lifestyle changes, optimal care of people with diabetes by the primary and secondary care teams to reduce risk of developing or worsening DR, risk reduction through population screening and the public health contribution of clinicians, including ophthalmologists, to reduce the impact of this condition in people with diabetes. Several of these aspects have been addressed in other parts of the guidelines including epidemiology, prevention- see section 2 and screening for DR – see section 8. This chapter therefore focuses