How good is the blood sugar control in children and adolescents with type 1 diabetes in Germany? The answer to this can be found in the DPV-Wiss database, in which the HbA1c values, among other things, in over 27000 children and adolescents are registered.

Today, one can live to a ripe old age with diabetes. The foundations for this are laid in childhood and adolescence. Those early years have a considerable influence on the later course of the disease. Good metabolic control in childhood can serve to prevent later complications.

Treatment Goals
Whether the blood sugar levels in the previous weeks have been normal or too high can be determined by measuring the HbA1c value. People without diabetes have a value of between 4% and 5%.

In children with diabetes, the HbA1c is measured every 8 to 10 weeks in the diabetes outpatient clinics. It should lie between 6% and 7.5%. This is the range which indicates that the blood sugar has been well controlled. International studies on thousands of patients with type 1 diabetes have repeatedly shown that HbA1c values of over 7.5% significantly raise the risk of future complications. The only way to prevent future complications is, therefore, to keep the blood sugar well controlled. 

People with diabetes, however, should never attempt to reach HbA1c values of people without diabetes. The risk of serious hypoglycaemic events would be far too high.  

Data for Research
An HbA1c value between 6% and 7% is the therapeutic goal. But what is the real situation in children and adolescents with type 1 diabetes today? How good is their metabolic state? Has it improved in the last few years? What actually influences the HbA1c values?

In order to answer such questions, the HbA1c values of over 27000 children and adolescents with diabetes are constantly being registered and analyzed in a giant database called the DPV-Wiss-Datenbank. DPV is a documentation programme which stands for Diabetes-Patienten-Verlaufsdaten.

Over 200 German diabetes centres and outpatient clinics that treat children with type 1 diabetes are taking part. They transmit their anonymous results to the DPV-Wiss database located at the University of Ulm. Here, the data is collated and made available for studies and research purposes. In this way, new findings for future improvements in the treatment of children with type 1 diabetes can be attained.

Factors that Influence Metabolic Control
Today, children suffering from diabetes have access to optimal treatment possibilities; there are long and short-acting insulins, insulin pens and pumps, and blood glucose meters. All these enable the accurate measuring and control of blood sugar.

With all this now at their disposal, have children really been able to manage their blood sugar and reach the therapeutic goals? Are there other factors we cannot influence that affect metabolic control? Does gender play any part? Does age affect the HbA1c value? Is it just our imagination or is it a fact that metabolic control of children is better in summer than in autumn and winter? Has the metabolic control of children improved at all in recent years? All these questions can be answered from the DPV-Wiss analyses.

The Role of Age
In both boys and girls, age plays a major role. Via the analysis, it has been found that the HbA1c value drastically surges higher as of the age of eight. It drops back as of the age of 17. The young children at kindergarten age attain much better readings than their counterparts in puberty.

This lies in the fact that the hormones released during puberty tend to cause huge swings in blood sugar levels. In addition, it is exactly in puberty that children with diabetes start to manage their diabetes themselves. This, in itself, poses huge challenges for those with diabetes.

Diabetes in Puberty
Puberty is experienced very differently from child to child, regardless of diabetes. Whereas some go through puberty very smoothly, others have a much rougher time accepting their condition. Those who find it harder to cope with all the additional stresses of puberty also find it harder to cope with their diabetes, which is often pushed into the background.

The hormones that are released during puberty have a negative influence on blood sugar levels, causing huge swings. Therefore, close personalized care and motivation are very important for the individual. This period poses great challenges for the parents as well as the diabetes team.

After puberty, the average HbA1c value sinks back again, and the metabolism stabilizes.

The Role of Gender
The data also shows that gender does play a role in HbA1c values. In all age ranges, girls do not rate as well as boys. This difference is not an indication that girls do not manage their diabetes as well as boys, but rather an indication of the potent influence the female sex hormones – much more pronounced in girls than in boys—have on the metabolism.

Summer versus Winter
The DPV-Wiss data shows that the average HbA1c values in January and February are at their highest, at 8.1%. In August and September they are at their lowest.

The values in January and February reflect the metabolic control of children in the winter months, in which they are less active than in summer. It is in the afternoon that this seasonal difference is most pronounced. Also, children catch more infections in winter. This also negatively influences blood sugar levels.

What Has Changed?
The question as to whether the metabolic control of children has improved in recent years is an important one, especially since the therapeutical possibilities have changed so much. Every child has access to a personalized treatment programme suited to his/her lifestyle. There are insulin pumps, various kinds of insulins, monitors that measure blood sugar in a matter of seconds, and many training courses offered for parents, children and adolescents, i.e., the best conditions for success. 

On the other hand, the children of today face tougher challenges, which negatively affect the blood sugar levels. The daily routine has changed in many families. In many cases, there are no regular mealtimes. Small children are often put in the charge of day care until the afternoon. Lunch, for many school children and adolescents, consists mainly of fast food. Many children spend most of their time before a computer or TV screen, whereby physical activity is pushed more into the background. All these factors influence metabolic parameters just as much as the regular administering of insulin according to a specific plan. Despite all this, have the patients been able to improve their readings in recent years? 

Good News
The answer, fortunately, is a qualified yes! The average HbA1c value has significantly dropped in recent years. The number of children with very well controlled blood sugar has risen; the number with inadequate control has fallen.

These results give credit to the families and diabetes teams across Germany, who are striving to improve future prospects for children and adolescents with diabetes. 

The average HbA1c in adolescents has fallen in the last decade from 8.9% to 7.6%. Throughout the years, adolescents have always been the group who have found it the hardest to manage their diabetes. Now, however, they have reached a level that is more typical of younger children. 

Even in the younger children of kindergarten age, the average HbA1c value between 2000 and 2002 fell to under 7.5% and has remained there ever since. Maybe this is because an increasing number of children at that age are now wearing pumps. However, this assumption cannot be confirmed through the DPV-Wiss data. For this, we need more studies are required. 

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Eva-Maria Gerstl MD
Diabetologist DDG 
Senior Doctor
Passau Child Clinic
E-mail: eva-maria.gerstl(at)kinderklinik-passau(dot)de