Insulin Pump Therapy Is Associated with Less Post-Exercise Hyperglycemia than Multiple Daily Injections: An Observational Study of Physically Active Type 1 Diabetes Patients

1 Human and Environmental Physiology Research Unit, University of Ottawa , Ottawa, Ontario, Canada .
Diabetes Technology &amp Therapeutics (Impact Factor: 2.11). 12/2012; 15(1). DOI: 10.1089/dia.2012.0168
Source: PubMed


Aerobic exercise typically decreases blood glucose levels in individuals with type 1 diabetes. It is currently unknown if glucose responses to exercise and recovery differ between patients on multiple daily insulin injections (MDI) and continuous subcutaneous insulin infusion (CSII).

Subjects and methods:
Nineteen (16 male, three female) physically active individuals with type 1 diabetes took part in this observational study. Interstitial glucose levels (blinded) were compared during 45 min of standardized aerobic exercise (cycling or running at 60% peak aerobic capacity) and during 6 h of postexercise recovery between individuals using MDI (n=9) and CSII (n=10) therapy.

Both MDI and CSII groups had similar reductions in glucose levels during exercise, but responses in early and late recovery differed (group × time interaction, P<0.01). Participants using MDI had greater increases in glucose throughout recovery compared with individuals with CSII. Two-thirds of the MDI patients experienced late-onset post-exercise hyperglycemia (blood glucose >12 mmol/L) compared with only 1/10(th) of the CSII patients (P<0.01).

Among individuals performing regular moderate-to-heavy intensity aerobic exercise, use of CSII helped to limit post-exercise hyperglycemia compared with MDI therapy and is not associated with increased risk for post-exercise late-onset hypoglycemia.

15 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: Physical exercise is firmly incorporated in the management of type 1 diabetes (T1DM), due to multiple recognized beneficial health effects (cardiovascular disease prevention being preeminent). When glycemic values are not excessively low or high at the time of exercise, few absolute contraindications exist; practical guidelines regarding amount, type, and duration of age-appropriate exercise are regularly updated by entities such as the American Diabetes Association and the International Society for Pediatric and Adolescent Diabetes. Practical implementation of exercise regimens, however, may at times be problematic. In the poorly controlled patient, specific structural changes may occur within skeletal muscle fiber, which is considered by some to be a disease-specific myopathy. Further, even in well-controlled patients, several homeostatic mechanisms regulating carbohydrate metabolism often become impaired, causing hypo- or hyperglycemia during and/or after exercise. Some altered responses may be related to inappropriate exogenous insulin administration, but are often also partly caused by the "metabolic memory" of prior glycemic events. In this context, prior hyperglycemia correlates with increased inflammatory and oxidative stress responses, possibly modulating key exercise-associated cardio-protective pathways. Similarly, prior hypoglycemia correlates with impaired glucose counterregulation, resulting in greater likelihood of further hypoglycemia to develop. Additional exercise responses that may be altered in T1DM include growth factor release, which may be especially important in children and adolescents. These multiple alterations in the exercise response should not discourage physical activity in patients with T1DM, but rather should stimulate the quest for the identification of the exercise formats that maximize beneficial health effects. © 2013 American Physiological Society. Compr Physiol 3:1309-1336, 2013.
    Comprehensive Physiology 07/2013; 3(3):1309-36. DOI:10.1002/cphy.c110040 · 4.74 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hypoglycemia is a major challenge of artificial pancreas systems and a source of concern for potential users and parents of young children with Type 1 diabetes (T1D). Early alarms to warn the potential of hypoglycemia are essential and should provide enough time to take action to avoid hypoglycemia. Many alarm systems proposed in the literature are based on interpretation of recent trends in glucose values. In the present study, subject-specific recursive linear time series models are introduced as a better alternative to capture glucose variations and predict future blood glucose concentrations. These models are then used in hypoglycemia early alarm systems that notify patients to take action to prevent hypoglycemia before it happens. The models developed and the hypoglycemia alarm system are tested retrospectively using T1D subject data. A Savitzky-Golay filter and a Kalman filter are used to reduce noise in patient data. The hypoglycemia alarm algorithm is developed by using predictions of future glucose concentrations from recursive models. The modeling algorithm enables the dynamic adaptation of models to inter-/intra-subject variation and glycemic disturbances and provides satisfactory glucose concentration prediction with relatively small error. The alarm systems demonstrate good performance in prediction of hypoglycemia and ultimately in prevention of its occurrence.
    Industrial & Engineering Chemistry Research 09/2013; 52(35). DOI:10.1021/ie3034015 · 2.59 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: It is relatively well known that moderate-intensity aerobic exercise increases the risk of hypoglycemia in individuals with type 1 diabetes. Conversely, brief high-intensity (anaerobic) activity can cause post-exercise hyperglycemia. Recent evidence has indicated that including small amounts of anaerobic activity, either in the form of short sprints or as resistance exercise (weight lifting), during aerobic exercise sessions may decrease the drop in blood glucose levels associated with moderate-intensity aerobic exercise. This review discusses the recent developments in the area of exercise and type 1 diabetes, with a particular focus on the effects of resistance exercise. Practical exercise recommendations, as well as suggestions for the future direction of research in this area, are also provided.
    Canadian Journal of Diabetes 12/2013; 37(6):420-6. DOI:10.1016/j.jcjd.2013.07.020 · 2.00 Impact Factor
Show more