Predictors of the maximal oxygen consumption in adult patients with type 1 diabetes treated with personal insulin pumps.

AIMS/INTRODUCTION: Regular physical activity for adults with type 1 diabetes mellitus improves cardiorespiratory fitness (CF) and quality of life. The aim of our study was to evaluate clinical and biochemical features that might be associated with CF in a homogenous group of adults with type 1 diabetes mellitus who are all treated with a personal insulin pump (continuous subcutaneous insulin infusion).

MATERIALS AND METHODS: We assessed CF in 62 patients (74.2% of whom were men) who fulfilled the eligibility criteria. To determine maximal oxygen consumption, the march-running test on the treadmill was carried out. Two hours before the test, the patients consumed a defined meal covered by a dose of rapid acting insulin analog that was reduced by 25% from their regular dose. Basal insulin infusion was reduced by 50% for an hour. Additionally, the Perceived Stress Scale-10 questionnaire was used to measure the perception of stress.

RESULTS: There was no episode of severe hypoglycemia during or after the test. In the final model, independent predictors of maximal oxygen consumption were sex, body fat percentage, lactate at 20 min after CF test and Perceived Stress Scale-10 score. Of interest, neither short-term (continuous glucose monitoring) nor long-term (glycosylated hemoglobin) metabolic control parameters were predictors of CF.

CONCLUSIONS: In our selected homogenous group of patients with type 1 diabetes mellitus treated with personal insulin pumps, higher CF was associated with a lower percentage of body fat, male sex, higher lactate level after the CF test and the Perceived Stress Scale-10 score. The proposed protocol in our cohort proved to be safe with regard to glycemic control.