Why some cases of retinopathy worsen when diabetic control improvesBMJ 1997; 315 doi: https://doi.org/10.1136/bmj.315.7116.1105 (Published 01 November 1997) Cite this as: BMJ 1997;315:1105
Worsening retinopathy is not a reason to withhold intensive insulin treatment
- E Chantelau, Professor of medicinea,
- E M Kohner, Emeritus professor of ophthalmic medicineb
- a Department of Medicine, Heinrich Heine University, D-40001 Düsseldorf, Germany
- b St Thomas's Hospital, London SE1 7EH
In the 1970s Engerman et al showed that strict control of diabetes could prevent the development of retinopathy in diabetic dogs.1 When close monitoring of glycaemia and methods of giving frequent insulin injections became possible in routine practice clinicians had great expectations that similarly strict control in humans could prevent the development of diabetic retinopathy and arrest or even reverse early lesions. These expectations were dashed, however, when it became clear that tightening control in patients with existing retinopathy could make the lesions worse.2 This normoglycaemic re-entry phenomenon has puzzled clinicians,3 and, although there is still much to learn about its mechanism, it is becoming clearer how to manage it.
Early findings that patients with varying degrees of retinopathy suffered a paradoxical worsening of their lesions as their diabetic control improved2 3 4 5 6 have been confirmed in a recent large study of non-insulin dependent diabetics started on insulin.7 But even before …