Epidemiology

• Decreasing incidence of nephropathy and retinopathy
• Impaired glucose tolerance
• Prevalence
• Risk factors for retinopathy & education
• Progression
• Incidence of retinopathy
• Low socio-economic status
• Leeds...still a big problem (a link)
• Wisconsin results 2009
• Erectile dysfunction is common
• late diagnsosis

Includes notes taken from speakers at EASDec meeting 2002

 

Decreasing incidence of nephropathy and retinopathy in type 1 diabetes

P Hovind et al

Figures for 2011  indicated 25% of diabetics have retiopathy, and this is severe in 8%.

 

Impaired glucose tolerance and diabetes and retinopathy

H A van Leiden

• see In Archives of Ophthalmology 2003
• high body mass (waist-hip ratio) increases retinopathy rate 9 times
• need to screen for impaired glucose tolerance

Prevalence of retinopathy

• in Leicester: see full paper on line
  • for every 10,000 people
    • nearly 68 were registered blind from diabetes
    • 27 from non-diabetic causes
  • indo-asian doubles risk of blindness, especially in males (60% diabetic)
  • smoking, alcohol, and elementary education were all important factors
  • see online or abstract
• see a similar paper
• Germany 2011   Japan 2011
• in the USA: Jama 2010  "In a nationally representative sample of US adults with diabetes aged 40 years and older, the prevalence of diabetic retinopathy and vision-threatening diabetic retinopathy was high, especially among Non-Hispanic black individuals."

 

Risk factors for retinopathy, E Bandurska-Stankiewicz, EASDec meeting 2002, notes

Education was the main risk factor. Other factors were similar to those discussed generally elsewhere on this site.

 

Other details

• diabetic retinopathy causes 11% blindness in Western countries
• smoking 20 cigarettes a day triples retinopathy progression rate
• patients are presenting with retinopathy as their diabetes is diagnosed, indicating they have diabetes for years unknowingly. This indicates the need for screening for diabetes, as recommended by the World Health Organisation. Between 7-14% patients present with diabetes AND retinopathy, depending on the study (Fuller, EASDec 2003).
• Many of the presentations emphasised points discussed elsewhere on this site, that is in theory retinopathy can usually be preventable (with tight sugar, blood pressure, and cholesterol control, and timely laser), but can at times be very difficult to treat successfully.
• In the Eurodiab study (Fuller, EASDec 2003), retinopathy was worse with
  • duration of diabetes
  • HbA1c
  • albumen excretion rate
  • waist diameter increasing
  • triglycerides
  • no relationship with smoking in this study
  • 600 patients had no retinopathy at baseline, but after 7.5 years, 56% had retinopathy
  • there is a suggestion that ACE inhibitors and angiotensin receptor antagonists can be used together and protect renal function
  • even blood pressure of 122 systolic cause more retinopathy than 115
  • inflammatory markers were related to retinopathy: TNFa and E selectin.
• Sosna, Czech, EASDec 2003, adds
  • retinal pigment epithelial atrophy protects against retinopathy, as does severe retinal scarring and optic atrophy
  • myopia -5d or more protects against retinopathy
  • vitreous loss & cataract surgery increase retinopathy, but phaco is much safer
  • (the timing of surgery on patients with macular oedema is controversial)
  • amblyopic probably protects
  • PVD protects
  • advanced glaucoma is protective
  • pancreas transplants protect
  • laser causes iatrogenic problems, such as macular burns
• In the Beaver Dam study (Fuller, EASDec 2003), retinopathy was present in 10% at baseline time of diagnosis, but after 20 years of diabetes in 80%.

 

Progression

• diabetic retinopathy causes 11% blindness in Western countries
• smoking 20 cigarettes a day triples retinopathy progression rate
• patients are presenting with retinopathy as their diabetes is diagnosed, indicating they have diabetes for years unknowingly. This indicates the need for screening for diabetes, as recommended by the World Health Organisation.
• Many of the presentations emphasised points discussed elsewhere on this site, that is in theory retinopathy can usually be preventable (with tight sugar, blood pressure, and cholesterol control, and timely laser), but can at times be very difficult to treat successfully.
• the incidence of blindness from type 1 is reducing, but from type 2 is increasing (Denmark, EASDec 2003, Jeppesen & Bek)
• see rapid progression...as Hba1c drops ~3%

Of 85 patients in 1990 with proliferative diabetic retinopathy, 57 deteriorated. If categorised in 1990 with 4 microaneurysms or less, patients generally did better versus the other with more that 4 microaneurysms. Thus even after laser for proliferation, the degree of maculopathy (as indicated by number of microaneurySsms) indicates the prognosis. (Denmark, EASDec 2003, Bek &J Kjaergaard).

 

Incidence of retinopathy

These studies here and here indicate that about 12% of people with diabetes are undergoing laser treatment of have had some in the past. But some diabetologists report much lower rates, perhaps 1%, probably because their patients have much better controlled diabetes. 7% of patients presenting with diabetes have retinopathy at presentation...does this represent a failure of screening for diabetes?

• there 2.35m diabetics in the UK (2.5m in 2010)
• 90% have type 2 diabetes
• Type 2 is increasing at 15% /year
• type 2 is 5 x commoner in non-white populations (some of this increase is genetic, some may be lifestyle such as lack of exercise)
• 50% of type 2 diabetes may be undiagnosed
• 8% of diabetics are blind, 12% of type 1
• retinopathy is still present in 12% of new cases

 

Low socio-economic status

This is a major risk factor, see  Poor reading skills and educational achievement make retinopathy much more likely. See other papers.  Some communities have very high retinopathy rates, here. Good care improves outcomes in the US.

Visual impairment in Cambridge    Leeds   70 blind registrations/year/1,000,000 UK

 

Type 1: 25 years, Wisonconsin results

After 25 years of diabetes, there is

• 25% incidence of macular oedema etc (Wisconsin 09).
• 42% prolideraftive retinopathy (Wisconsin 09).
• 83% retinopathy (Wisconsin 09).

 

Erectile dysfunction is common

See

 

Late diagnosis 

This is very common, even in wealthy areas such as North Birmingham. 15% of patients have retinopathy at presentation, and diabetes may have been present 5-9 years previously BJO 11

This paper indicates there is no simple cut off point for the diagnosis of diabetes; 'detectable retinopathy occurs 5.77 years before diagnosis. (This is not the serious retinopahy that needs laser...that takes a few  years longer to develop.