[How often does decreased consciousness of hypoglycaemia occur in children and adolescents with diabetes type 1 and what are its consequences?]

Abstract

The inability of the patient to recognize the risk of hypoglycemia is a very frequent phenomenon, but it is also often an underestimated complication in diabetes treated with insulin. The results of DCCT trial revealed that intensification in insulin therapy increases three-fold the risk of severe hypoglycaemia. Feeling the state of hypoglycaemia is the basic defensive mechanism in patients with diabetes type 1, making possible to start the self treatment. The decreased consciousness of hypoglycaemia makes limitations to intensive insulin therapy, which main aim is to stop later complications. THE AIM OF THE STUDY was to answer the questions: 1. How often does lack of consciousness of hypoglycaemia occur in children and adolescents with diabetes type 1. 2. What are the possible factors influencing appearance of hypoglycaemia. 3. Is lack of hypoglycaemia consciousness of a risk factor for severe hypoglycaemia.

Material and methods: The study was carried out on 318 patients aged x=13.6 yrs (4-21), suffering from diabetes, mean 6.6 yrs (2-18). The study was retrospective taking into consideration the period from 1.01.1998 to 31.12.2002.

Results: In the analysis of the questionnaire assessing the occurrence of hypoglycaemia it was found that 82 patients (25.8%) have problems with feeling the state of hypoglycaemia. We analyzed the influence of time of lasting diabetes and we found that patients with a longer duration of the disease more frequently have problems with feeling hypoglycaemia, 57% patients with lack of hypoglycaemia consciousness have bad metabolic control of the disease. In the analyzed period, 64 incidences of severe hypoglycaemia in 48 patients (30 boys and 18 girls) were found. In patients with lack of consciousness of feeling hypoglycaemia the incidences of severe hypoglycaemia occurred ten times more frequently compared to patients who feel hypoglycaemia. Sleeping makes it impossible to perceive early symptoms of hypoglycaemia: in our patients 51 severe incidences (79.7%) occurred at 1.00-3.00 a.m., 6 (9.3%) occurred at daybreak and 7 (11%) in the evening.

Conclusions: 1. In patients with diabetes type 1 the lack of hypoglycaemia consciousness occurs in about 25%. 2. The lack of hypoglycaemia consciousness is closely connected with time of diabetes duration and with recurrence of hypoglycaemia incidences. 3. Patients with lack of hypoglycaemia consciousness are at greater risk for severe hypoglycemia.