General practice management of type 2 diabetes


Diabetic retinopathy
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☰ Table of contents


Recommendations

Reference

Grade*

Ensure that all people with diabetes have a dilated fundus examination and visual acuity assessment at the diagnosis of diabetes and at least every two years

158
NHMRC, 2008

None provided (Level I evidence)

Examine higher risk patients (eg longer duration of diabetes, or poor glycaemic control, blood pressure or blood lipid control) without diabetic retinopathy at least annually

158
NHMRC, 2008

None provided (Level I evidence)

Conduct annual screening for Aboriginal or Torres Strait Islander peoples with diabetes

158
NHMRC, 2008

None provided (Level IV evidence)

*Refer to Summary, explanation and source of recommendations for an explanation of the level of evidence and grade of evidence

 

 


Clinical context


Diabetic retinopathy (DR) occurs as a result of microvascular disease of the retina, and causes visual impairment and blindness, and affects up to one in three people with diabetes.

DR is categorised as either:

  • non-proliferative DR
  • proliferative DR.

Non-proliferative DR affects 19.3% of people with diabetes, while 2.1% may have proliferative DR and 3.3% may suffer macular oedema.

Non-proliferative DR may be asymptomatic and is characterised by retinal haemorrhages and exudates. Proliferative DR is characterised by new blood vessel growth (neovascularisation), which may lead to severe complications and blindness. Diabetes-related macular oedema is the leading cause of vision impairment with diabetes and occurs when exudates impact the macula. Tight control of blood glucose and blood pressure reduces the risk of onset and progression of diabetic eye disease in type 2 diabetes.

With good screening and care, visual impairment due to diabetes can be avoided for the vast majority of patients.

Two studies have prospectively assessed the effect of fenofibrate on microvascular disease, principally retinopathy. In both the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) and Action to Control Cardiovascular Risk in Diabetes (ACCORD) studies, patients randomised to fenofibrate therapy had a significant reduction in retinopathy and need for laser surgery.159 Additionally, in FIELD, there was a reduction in peripheral neuropathy complications and an improvement in proteinuria, suggesting a more generalised effect on microvascular disease. In Australia, the TGA has approved the use of fenofibrate for the treatment of diabetic retinopathy. Its use in patients with diabetes with evidence of retinopathy should now be considered. The benefits on retinopathy were not dependent on the patient having dyslipidaemia.159

Retinal photography

Retinal photography is technically simple and now usually performed within the Australian community by GPs, optometrists and ophthalmologists. Training is required to ensure quality of image interpretation. Some isolated general practices and Aboriginal health services are providing their own retinal photography services with support through telemedicine.

People whose retinal images suggest they may be at increased risk of having, or at some point developing, sight-threatening retinopathy should be referred for ophthalmology.

NB: A new item on the MBS for retinal photography with a non-mydriatic retinal camera will be available for general practice use from November 2016. The listing is expected to benefit Aboriginal and Torres Strait Islander peoples and communities in rural and remote locations where there is limited access to optometric and ophthalmic services to diagnose DR.


In practice


Assess all patients with type 2 diabetes for risk factors (refer to Box 6).

Box 6. Risk factors for development and progression of diabetic retinopathy

  • Existing diabetic retinopathy 
  • Poor glycaemic control
  • Duration of diabetes >10 years
  • Microalbuminuria
  • Dyslipidaemia
  • Anaemia
  • Pregnancy


The aim is to prevent vision loss and this is best done with regular review of fundi, early detection and optimisation of therapy.

GPs can monitor patients for diabetic eye disease if they are confident of their technique and examine the eyes through dilated pupils or have their own retinal camera. Where practitioners are not comfortable with fundoscopy and assessment of the retina, referral to an ophthalmologist or optometrist is recommended.

Monitoring involves:

  • visual acuity (with correction)
  • cataracts (refer to Section 10.2. Other ophthalmological)
  • retinopathy (examine with pupil dilation or retinal camera, or refer to an optometrist or ophthalmologist).

Initial and then intermittent ongoing referral to an ophthalmologist or optometrist is still recommended for DR or peripheral retinopathy, which can be treated with laser photocoagulation therapy to prevent visual loss secondary to retinal haemorrhage.

Patients should be reviewed at least every two years and more frequently if problems exist.


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  1. Simo R, Hernandez C. Prevention and treatment of diabetic retinopathy: evidence from large, randomized trials. The emerging role of fenofibrate. Rev Recent Clin Trials 2012;7(1):71–80.