Rapid lowering of blood glucose in people with mild or moderate diabetic retinopathy does not worsen this eye complication

A new study conducted in people with type 2 diabetes has revealed interesting results about the treatment of hyperglycemia and its relationship with diabetic retinopathy, an eye complication that often affects people with diabetes.

The research "Rapid Reduction of HbA1c and Early Worsening of Diabetic Retinopathy: A Real-World Population-Based Study in Subjects With Type 2 Diabetes", published in the prestigious diabetes journal Diabetes Care, suggests that a rapid reduction of HbA1c, a key measure in the glycemic control of diabetes, does not worsen retinopathy in people who already had a mild or moderate form of this complication”.

This is good news for people with retinopathy and healthcare professionals, as it implies that improving blood glucose control needs not be delayed for fear of worsening diabetic retinopathy in these cases. This finding may contribute to improving the control of diabetes and its complications.

Different research groups have participated in the study, and it has been led by Josep Franch Nadal, coordinator of the Primary Care Diabetes Group (DAP_Cat) of the Primary Care Research Institute Jordi Gol (IDIAPJGol), Dídac Mauricio, from the Research Institute of the Hospital de la Santa Creu i Sant Pau (IIB Sant Pau), and Rafael Simó, from the Vall d'Hebron Research Institute (VHIR). All of them also belong to the Center for Biomedical Research in the Network of Diabetes and Associated Metabolic Diseases (CIBERDEM).

Knowing whether a rapid drop in blood glucose levels was related to early worsening of diabetic retinopathy is a matter of concern to healthcare professionals, as diabetic retinopathy is one of the most common complications of diabetes and the leading cause of avoidable blindness in the adult population. The prevalence of this complication is high and affects at least 2 out of 10 people with diabetes, and this number is expected to increase. The study analyzed data from more than 1,000 people with type 2 diabetes and mild or moderate diabetic retinopathy. The researchers looked at the relationship between lowering blood glucose levels (HbA1c) of more than 1.5% in less than 12 months or more than 2% in less than 6 months and worsening of diabetic retinopathy .

According to Josep Franch, coordinator of the DAP_Cat, "many doctors were afraid to be aggressive when it comes to lowering sugar and could think that it was better to do it little by little, even if this increased the risk of suffering from other non-retinopathic complications, but with this study, which is the first to be done under conditions of routine clinical practice, we have seen that there is no argument for delaying glycemic control until the goals we desire for each patient."

HbA1c (glycosylated hemoglobin) is a clinical test used to measure blood glucose control over time. It is a fraction of hemoglobin (a protein found in red blood cells that carries oxygen to the body's tissues) that binds to glucose. For people with diabetes, HbA1c is a key measure to assess blood glucose control and disease management. A high HbA1c level indicates poor diabetes control and a higher risk of associated complications, such as diabetic retinopathy, which affects the eyes.

It should be noted that this study focused on people with mild to moderate diabetic retinopathy, and not on people with more advanced stages of retinopathy. In the less frequent situation of severe diabetic retinopathy, and given the lack of evidence in usual conditions of clinical practice, it is not possible to establish the safety or danger of the rapid lowering of blood glucose.