[Blood glucose and ketone monitoring in type 1 diabetic patients in the controlled environment of a summer camp].

INTRODUCTION

Control of blood ketone levels and glycemia is advisable in certain situations in type 1 diabetic children and adolescents. The aims of this study were to assess the relationship between glycemia, ketonemia and ketonuria in children and adolescents in a summer camp under different conditions (fasting, casual hyperglycemia, moderate physical exercise) and to assess the utility of ketonemia determinations in diabetes control during this time.

PATIENTS AND METHODS

There were 47 participants (25 boys and 22 girls), with a mean HbA1c determination prior to enrollment of 7.7 +/- 1.5 %. The mean age was 11.7 +/- 1.8 years and the mean time from onset of diabetes was 3.0 +/- 2.7 years. The mean body mass index was 18.3 +/- 3.9 kg/m2 (SDS -0.16 +/- 0.44), the mean insulin dose was 0.8 +/- 0.4 U/kg/ day, and the number of doses per day was between 2 and 4 (median = 3). Blood glucose and ketones (both measured with the Optium system, Abbott Diabetes Care) and urine ketones (Ketodiastix, Bayer) were determined in different situations. Statistical analysis was performed with the SPSS 11.5 program.

RESULTS

Ketonemia results 45 minutes before and after moderate physical activity showed no significant increase in ketones (0.1 +/- 0.03 vs 0.23 +/- 0.07 mmol/l, ns). Preprandial blood ketone levels of > or = 0.5 mmol/l were found in 17.02 % of participants. Ketonemia was resolved during the first hour in all participants except one, in whom ketonemia resolved in 3 hours. Blood ketones were higher before breakfast than during the rest of the day (0.12 +/- 0.17 vs 0.02 +/- 0.05, p < 0.001). The mean glycemia level with ketosis (beta -HB > or = 0.5 mmol/l) was 174.5 +/- 64.7 mg/dl, a value slightly higher than the overall mean glycemia value (156.87 +/- 87.8 mg/dl). Ketonuria could not be measured in a high percentage of participants due to the difficulty of obtaining samples (between 24.5 % and 58.6 % in the different study groups).

CONCLUSIONS

Measurement of glycemia together with ketonemia in a summer camp allows reliable follow-up of glycemic control to be performed. Ketonemia usually occurred before breakfast in parallel with slightly elevated glycemia, but resolved quickly. Moderate physical activity for 45 minutes does not seem to significantly increase blood ketones if metabolic control is normal. beta -HB is a useful parameter to determine whether moderate physical exercise is advisable or not. The lack of urinary ketone tests due to the difficulties of obtaining a sample can currently be solved by blood ketone measurement.