Causes, symptoms and risk factors of diabetic retinopathy

Millions of Germans suffer from the metabolic disorder diabetes. The possible damage to the blood vessels can also have consequences for the eyes. Learn more about causes, symptoms and risks.

How does diabetic retinopathy develop?

Poor blood sugar levels and high blood pressure over a long period of time have a damaging effect on blood vessels. Damage to the small capillaries in the eye is also possible. Brittle and thickened vessel walls as well as vasodilatation are the result. This creates diabetic retinopathy caused by diabetes.

There is a risk of fluid getting into the retina. Deposits in the vessels can also reduce the oxygen supply to the eye. If there is no timely treatment, irreversible visual impairment occurs.

What are the causes of diabetic retinopathy?

Several circumstances enable diabetic retinopathy. In general, an unhealthy load on the blood vessels in the eye is the main cause, which is caused by various influences. The following risk factors are included:

  • Type 1 diabetes and type 2 diabetes

    Diabetes mellitus often leads to damage of the blood vessels, especially in the case of long-term exposure, caused by an insufficiently controlled blood sugar level. Proliferative diabetic retinopathy is more common in adolescents with type 1 diabetes than in type 2 diabetes. However, from the time of diagnosis, regardless of whether it is type 1 diabetes or type 2 diabetes, we recommend annual preventive examinations by an ophthalmologist.

  • High blood pressure

    Additionally persistent and untreated high blood pressure damages the blood vessels and is a risk factor for the development of diabetic retinopathy. Medical supervision and regulation is crucial.

  • Duration of illness

    The risk of developing retinal changes caused by diabetes increases with the duration of the illness. This applies to both diabetes and high blood pressure.

  • Puberty and pregnancy

    Both during puberty and pregnancy, existing diabetic retinopathy can worsen.

  • Smoking and alcohol consumption

    Smoking and excessive consumption of alcohol have negative effects on the blood vessels and thus also on the health of the eyes. Try to become or stay a non-smoker and avoid alcohol.

What are the symptoms of diabetic retinopathy?

In the early stages, diabetic retinopathy usually develops without symptoms, such as pain or visual impairment. That is why it often goes unnoticed by patients. In order to avoid permanent damage, regular check-ups by an ophthalmologist are all the more important for diabetics, even if they have no symptoms.

In the initial stage, changes in contrast perception and reduced color vision can be perceived as symptoms.

Noticeable visual impairment or sudden loss of vision are most often symptoms of late-stage diabetic retinopathy. Some of the damage caused here can then also be irreparable. However, at this stage an attempt should be made to maintain the existing function and treat the findings.

Other symptoms of diabetic eye diseases

  • With diabetic macular edema, symptoms such as out-of-focus, distorted or blurred vision occur.
  • Blind or dark spots, as well as a gray or red haze in the field of vision, indicate bleeding into the vitreous space or damage to the retina.
  • Sudden severe visual impairment also indicates bleeding into the vitreous space.
  • Flashes of light or soot rain occur with an initial detachment of the retina – in this case an ophthalmologist should be consulted quickly as there is a risk of blindness.

Further information on diabetes and the eye

An early diagnosis of diabetic eye diseases is essential to avoid permanent damage. Our ophthalmological practice specializes in the detection and treatment of diabetes-related eye diseases. We use the latest technologies in ophthalmic medicine, work very sensitively, absolutely sterile and particularly precisely, so that examinations and treatment can be experienced quickly and painlessly.

  • Dr Lemmen Vorschaubild

    PD Dr. Klaus Dieter Lemmen


    Many years of experience as senior physician and chief physician in specific eye clinics. Focus: Age-related macular degeneration, retinal diseases and diabetes-induced retina diseases

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  • Dr. K Vahdat Vorschaubild

    Dr. Katarina Vahdat


    Focus: general ophthalmology and pediatric ophthalmology. Treatment of various macula diseases, diabetic retinopathy and diabetic maculopathy

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