Physical activity and sedentary behavior levels in children and adolescents with type 1 diabetes using insulin pump or injection therapy - The importance of parental activity profile

Healthy weight and overweight adolescents with type 1 diabetes mellitus do not meet recommendations for daily physical activity and sleep

AIMS

Physical activity (PA) plays an important role in the prevention of cardiovascular disease (CVD), particularly in individuals with type 1 diabetes mellitus (T1DM) who are at increased risk. Our aim was to determine levels of moderate-to-vigorous physical activity (MVPA), sedentary behaviour and sleep in adolescents with T1DM, and identify barriers to PA.

METHODS

Participants aged 12-18 with T1DM wore an accelerometer and continuous glucose monitor for 24 h over 7-days. Data was processed into PA metrics and sleep. Pearson correlations were used to test associations between MVPA and metabolic measures. Barriers to PA were measured using a questionnaire.

RESULTS

Thirty-seven adolescents provided valid accelerometer data. Mean daily MVPA was 44.0 min [SD 17.6] with 16.2% achieving the guideline of ≥ 60 min/day. Participants had 11 h [SD 1.2] of sedentary behaviour and 7.6 h [SD 1.5] of sleep/day. There was no difference in MVPA in overweight or obese (53.8%) vs. healthy weight (44.2%) adolescents (45.0 min [SD 16.6] vs. 43.1 min [SD 18.8]). Only 39.6% reported one or more diabetes specific barrier to PA.

CONCLUSION

Adolescents with T1DM engage in insufficient MVPA and sleep, irrespective of body weight status, suggesting the need for targeted interventions.

Physical Activity Management for Youth With Type 1 Diabetes: Supporting Active and Inactive Children

Regular physical activity and exercise are important for youth and essential components of a healthy lifestyle. For youth with type 1 diabetes, regular physical activity can promote cardiovascular fitness, bone health, insulin sensitivity, and glucose management. However, the number of youth with type 1 diabetes who regularly meet minimum physical activity guidelines is low, and many encounter barriers to regular physical activity. Additionally, some health care professionals (HCPs) may be unsure how to approach the topic of exercise with youth and families in a busy clinic setting. This article provides an overview of current physical activity research in youth with type 1 diabetes, a basic description of exercise physiology in type 1 diabetes, and practical strategies for HCPs to conduct effective and individualized exercise consultations for youth with type 1 diabetes.

The impact of physical activity, quality of life and eating habits on cardiometabolic profile and adipokines in youth with T1D

PURPOSE

Individuals with Type-1-Diabetes (T1D) are at higher risk of having premature cardiovascular-disease (CVD). Physical activity and healthy lifestyle are major components in the prevention of diabetes' related comorbidities and complications. The aim of this study was to investigate the impact of physical activity, eating habits and quality of life in children and adolescents with T1D on diabetic control, cardiovascular and biochemical profile, infection indices, and adipokine levels.

METHODS

This cross-sectional study involved 80 participants (36 boys/44 girls) with T1D, aged (mean ± SD) 14.9 ± 3.4 years, who attended the Diabetes and Metabolism Clinic of a University Children's Hospital, using anthropometric studies, lipid profile, high-sensitivity-C-Reactive-Protein(hs-CRP), Interleukin-6(IL6), leptin and adiponectin levels. Physical activity was assessed with pedometers (total-steps/week) and questionnaire.

RESULTS

In 20(25%) children the level of exercise was >75th percentile, in 20(25%) <25th percentile and in 40(50%) children ranged between 25-75th percentile, respectively. Higher levels of physical activity were associated with weight (beta = -0.053, p < 0.001), waist circumference (beta = -0.077, p < 0.001), BMI (beta = -0.167, p = 0.009), muscle mass (beta = -0.0619, p = 0.001) and HDL-C (beta = 0.039, p = 0.033). Quality of life was positively related to weight (beta = 5.49511, p = 0.002), waist circumference (beta = 6.593345, p = 0.012), muscle mass (beta = 7.324088, p < 0.001) and T1D duration (beta = 19.22442, p = 0.005). Lipid profile was positively associated with sweets and chocolate consumption (beta = 0.348, p < 0.05), while vegetable (beta = -0.245, p < 0.05) and white milk consumption (beta = -0.2295, p < 0.05) were negatively associated with waist/height ratio.

CONCLUSIONS

In the present study, higher levels of physical activity were associated with improved lipid profile (HDL-C, triglycerides) and body composition [waist circumference, Body-Mass-Index (BMI] of children and adolescents with T1D. Higher scoring in quality-of-life questionnaires were related to older children with longer diabetes duration. Unhealthy eating habits unfavorably affected lipid profile and body composition in T1D youth.

Barriers to Physical Activity in Children and Adults Living With Type 1 Diabetes: A Complex Link With Real-life Glycemic Excursions

OBJECTIVES

Ever since the first research on barriers to physical activity (PA) highlighting fear of hypoglycemia as a major barrier, many studies have attempted to understand their demographic and behavioural determinants. However, no research has been conducted on whether these perceived barriers toward PA are based on real-life-experienced adverse glycemic effects of exercise.

METHODS

Sixty-two adults and 53 children/adolescents living with type 1 diabetes, along with their parents, completed the Barriers to Physical Activity in Type 1 Diabetes-1 (BAPAD-1) questionnaire on barriers to PA. Continuous glucose-monitoring data were collected during 1 week of everyday life for 26 adults and 33 children/adolescents. Multiple linear regressions were used to explore links between BAPAD-1 scores and glycemic excursions experienced during and after everyday-life self-reported PA sessions, controlling for behavioural (accelerometry) and demographic confounders.

RESULTS

In children/adolescents, the more time spent in hypoglycemia on nights after PA sessions, the more they reported hypoglycemic risk as a barrier (ß=+0.365, p=0.034). Conversely, in adults, the higher the proportion of PA sessions accompanied by a drop in blood glucose, the less hypoglycemia was a barrier (ß=-0.046, p=0.004). In parents, BAPAD-1 scores were unrelated to children/adolescents' everyday-life exercise-induced hypo/hyperglycemia.

CONCLUSIONS

In children/adolescents, fear of hypoglycemia was predominant in those exposed to nocturnal hypoglycemia associated with PA sessions. In adults, fewer barriers may mean they accept a bigger drop in their glycemia during PA. This shows the importance of finding and promoting age-specific solutions to prevent exercise-induced hypoglycemia.

Dietary Intake and Physical Activity of Thai Children and Adolescents with Type 1 Diabetes Mellitus

Appropriate dietary intake and physical activity (PA) are essential for glycemic control and optimal growth in youth with type 1 diabetes (T1D). Thus, this study aimed to compare dietary intake and PA between youth with T1D and healthy controls. One hundred Thai youth with T1D and 100 age-matched healthy participants were recruited. A 3-day food record was completed and converted into nutrient intake data. PA data were collected via interview. Participants with T1D had a significantly higher mean ± SD carbohydrate (50.8 ± 6.8% vs. 46.2 ± 7.5%, p < 0.01), lower fat (32.4 ± 5.9% vs. 35.9 ± 6.4%, p < 0.01), and lower protein (16.8 ± 2.6% vs. 17.9 ± 3.5%, p = 0.01) intake compared to controls. Fifty percent of T1D participants and 41% of control participants consumed saturated fat more than recommendations (p = 0.20). Participants with T1D had a higher median (IQR) calcium intake compared to controls (474 (297−700) vs. 328 (167−447) mg/day, p < 0.01). Both groups consumed less fiber and more sodium compared to recommendations. Both groups had inadequate PA. Participants with T1D had significantly less PA compared to controls (25 (13−48) vs. 34 (14−77) minutes/day, p = 0.04). In addition to the need for counseling that promotes consumption of more dietary fiber and calcium and less saturated fat and sodium, the benefits of performing regular exercise need to be emphasized among youth with T1D.

Association between high levels of physical activity and improved glucose control on active days in youth with type 1 diabetes

BACKGROUND

Sixty minutes per day of at least moderate to vigorous physical activity (MVPA) is recommended for children for a variety of physical and psychological reasons. Adherence to these guidelines is confounded by challenges with glucose control during exercise in type 1 diabetes (T1D).

OBJECTIVES

This study examined the potential association between physical activity level on active days and glucose control in youth with T1D.

METHODS

Blinded continuous glucose monitors (CGM: Abbott Libre Pro) and physical activity data as measured from a body monitor patch (Metria IH1) were collected for up to 3 weeks in youth aged 9-17 years with T1D. The association between physical activity levels, expressed as mean active metabolic equivalent minutes (MET-minutes) per day, with CGM-based mean glucose, percent time in range (TIR: 70-180 mg/dl), % time above range (TAR) and % time below range (TBR) were assessed using a linear regression model adjusted for age, gender, and baseline HbA1c.

RESULTS

Study participants were deemed physically active, as defined by at least 10 min of continuous moderate-to-vigorous activity, on 5.2 ± 1.9 days per week, with a median accumulated physical activity time of 61 [IQR: 37-145] minutes per day. Higher physical activity levels were associated with lower mean glucose levels (r = -0.36; p = 0.02) and lower TAR (r = -0.45; p = 0.002) on active days. Higher activity levels were also associated with greater TIR (r = 0.54; p < 0.001) without being associated with more, or less, TBR.

CONCLUSIONS

Higher amounts of physical activity are associated with improvements in TIR without significantly increasing TBR. These data suggest that youth ages 9-17 years with T1D can benefit from a high level of physical activity without undue fear of hypoglycemia.

Youth and Parent Perspectives on the Acceptability of a Group Physical Activity and Coping Intervention for Adolescents With Type 1 Diabetes

PURPOSE

To examine youth and parent perspectives on the acceptability of Bright 1 Bodies, a group physical activity and coping intervention for adolescents with type 1 diabetes mellitus (T1DM).

METHODS

Adolescents participated in 12 weekly sessions of moderate to vigorous physical activity and discussion with peers with T1DM. Adolescents completed an exit survey measuring satisfaction with the intervention on a 5-point Likert scale. Semistructured interviews were conducted with adolescents and at least one parent. Qualitative description was used to develop themes that summarize the acceptability of the intervention.

RESULTS

Mean scores for survey subscales were: 4.5 (SD = 0.39) for program components and strategies, 4.4 (SD = 0.44) for comfort with the intervention, and 4.3 (SD = 0.62) for instructors. Themes included: (1) adolescents and parents valued being around others with T1DM and their families, (2) the intervention helped adolescents gain knowledge and reinforce diabetes self-management behaviors, (3) challenges included convenience and sustaining participant engagement, and (4) adolescents intended to sustain physical activity and diabetes self-management behaviors after the intervention.

CONCLUSIONS

Adolescents and parents viewed the intervention as acceptable across multiple domains. Participants valued the group aspect of the intervention, and future interventions would benefit from integrating social interactions with others with T1DM.

Effects of 12 weeks of recreational football (soccer) with caloric control on glycemia and cardiovascular health of adolescent boys with type 1 diabetes

OBJECTIVE

To determine the effects of recreational football combined with caloric control on glycemia and cardiovascular health of adolescent boys with type 1 diabetes.

BACKGROUND

Though 12 weeks of physical activity alone improves the health of people with type 1 diabetes, there is little evidence that physical activity alone can improve glycemia in 12 weeks.

RESEARCH DESIGN AND METHODS

The participants were divided into four groups as follows: football with diet, football-only, diet-only, and the control groups. Each group consisted of 10 participants. The football with diet and the football-only groups had 1.5 h of football twice a week for 12 weeks. The following outcomes were measured before and after 12 weeks: Glycated hemoglobin, fasting blood glucose, total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, and resting blood pressures. Changes were considered significant when p ≤ 0.050 and common language effect size ≤42% or common language effect size ≥58%.

RESULTS

Glycated hemoglobin decreased in the football with diet group (mean change (standard deviation) = -0.9 (1.0) %, p = 0.019, and common language effect size = 31.5%) and was different from the control group (p = 2.4 × 10^-4 and common language effect size = 95.5%.). However, none of the intervention groups showed a clear change in blood lipids nor blood pressure.

CONCLUSIONS

12 weeks of combined football with diet intervention provides the greatest improvement in glycemia in adolescent boys with type 1 diabetes.

Comparison of two carbohydrate intake strategies to improve glucose control during exercise in adolescents and adults with type 1 diabetes

BACKGROUND AND AIMS

During aerobic physical activity (PA), hypoglycemia is common in people with type 1 diabetes (T1D). Few studies have compared the effectiveness of different carbohydrate (CHO) intake strategies to prevent PA-induced hypoglycemia. Our objective was to compare the efficacy of two CHO intake strategies, same total amount but different CHO intake timing, to maintain glucose levels in the target range (4.0-10.0 mmol/L) during PA in people with T1D.

METHODS AND RESULTS

An open-label, randomized, crossover study in 33 participants (21 adults; 12 adolescents). Participants practiced 60 min PA sessions (ergocyle) at 60% VO_2peak 3.5 h after lunch comparing an intake of 0.5 g of CHO per kg of body weight applied in a pre-PA single CHO intake (SCI) or in a distributed CHO intake (DCI) before and during PA. The percentage of time spent in glucose level target range during PA was not different between the two strategies (SCI: 75 ± 35%; DCI: 87 ± 26%; P = 0.12). Hypoglycemia (<4.0 mmol/L) occurred in 4 participants (12%) with SCI compared to 6 participants (18%) with DCI (P = 0.42). The SCI strategy led to a higher increase (P = 0.01) and variability of glucose levels (P = 0.04) compared with DCI.

CONCLUSIONS

In people living with T1D, for a 60 min moderate aerobic PA in the post-absorptive condition, a 0.5 g/kg CHO intake helped most participants maintain acceptable glycemic control with both strategies. No clinically significant difference was observed between the SCI and DCI strategies. ClinicalTrials.gov Identifier: NCT03214107 (July 11, 2017).

Continuous Blood Glucose Monitoring Increases Vigorous Physical Activity Levels and Is Associated With Reduced Hypoglycemia Avoidance Behavior In Youth With Type 1 Diabetes

The primary goal of this study was to explore physical activity (PA) levels, hypoglycemia fear scores and hypoglycemia episodes according to insulin administration and blood glucose monitoring methods in youth with type 1 diabetes (T1D). A self-administered questionnaire was completed by 28 children and 33 adolescents with T1D, and their PA was assessed. Hypoglycemia episodes, fear of hypoglycemia scores, insulin therapy (pump vs. injection) and blood glucose monitoring (continuous blood glucose monitors [CGMs] vs. blood glucose meters) methods are reported in the present work. There were no significant differences in the number of hypoglycemic episodes, child hypoglycemia fear survey behavior or total scores, or any components of the PA profile between youth using injections and those using a pump. However, these variables differed significantly when compared according to blood glucose monitoring method (CGMs vs. blood glucose meters): 41.2 vs. 81.8, p<0.01; 1.03 ± 0.05 vs. 2.6 ± 0.63, p<0.01; 1.09 ± 0.43 vs. 2.94 ± 0.22, p<0.01; and 222 ± 18 vs. 49 ± 11, p<0.01 (for total time in vigorous PA in minutes per week), respectively. CGM use correlated significantly with VPA levels (β=0.6; p=0.04). Higher VPA levels were associated with higher child hypoglycemia fear survey behavior scores (β=0.52; p=0.04). The latter correlates negatively with the number of episodes of hypoglycemia in the past 12 months in all category groups. The type of insulin injection was not associated with more activity in youth with T1D. In contrast, CGM use may be associated with increased vigorous PA among T1D youth. Those with higher hypoglycemia fear survey behavior scores engaged in more VPA and had fewer hypoglycemia episodes. Although CGM use ensures continuous monitoring of glycemia during exercise, increasing hypoglycemia avoidance behavior is still a necessary part of exercise management strategies in active youth with T1D.

Vigorous Physical Activity Is Associated With Better Glycated Hemoglobin and Lower Fear of Hypoglycemia Scores in Youth With Type 1 Diabetes: A 2-Year Follow-Up Study

To correlate glycated hemoglobin (HbA1c) and fear of hypoglycemia scores with physical activity (PA) levels in children and adolescents with type 1 diabetes (T1D) over a period of 2 years. Twenty-eight children and 33 adolescents with T1D have been assessed for their PA profile. Personal and medical data for the patients were collected at baseline (visit 0: V0), 1 year later (V1), and 2 years later (V2). At baseline, children with T1D engaged in less moderate to vigorous PA (MVPA) (p < 0.01) per day than adolescents. These results did not differ across visits. On the contrary, adolescents spent fewer time in vigorous physical activity (VPA) (p < 0.01) than children did (p < 0.01). Fear of hypoglycemia scores correlated significantly with VPA levels (β = −0.41, p = 0.03; β = −0.44, p = 0.06; β = −0.61, p = 0.001). For HbA1c (%), significant correlations were reported with VPA levels (β = −0.54, p = 0.02; β = −0.47, p = 0.03; β = −0.62, p = 0.01) across visits. Body mass index percentile correlated with total screen time (β = 0.28, p = 0.02; β = 0.29, p = 0.01; β = 0.31, p = 0.04) and overall PA levels (β = −0.52, p = 0.02; β = −0.42, p = 0.03; β = −0.42, p = 0.01). Performing more vigorous PA a day is associated with better HbA1c with lower perceived fear of hypoglycemia among youth with T1D. Therefore, dedicating more time in VPA may be an appropriate advice for patients with T1D.

Episodes of severe hypoglycemia is associated with a progressive increase in hemoglobin A1c in children and adolescents with type 1 diabetes

OBJECTIVE

To investigate the trajectory in glycemic control following episodes of severe hypoglycemia (SH) among children and adolescents with type 1 diabetes (T1D).

METHODS

A Danish national population-based study comprising data from 2008-17. SH was defined according to the 2014 ISPAD guidelines. A mixed model was applied with HbA1c as outcome and SH episodes and time since first episode as explanatory variables. Data were adjusted for age, gender and diabetes duration.

RESULTS

A total of 4244 children (51.6% boys) with 18 793 annual outpatient visits were included. Mean (SD) age at diabetes onset was 9.0 (4.1) years. Median diabetes duration at inclusion in the study was 1.2 (Q1 = 0.9, Q3 = 3.0) years, and median diabetes duration at last visit was 5.0 (Q1 = 2.7, Q3 = 8.1) years. A total of 506 children experienced at least one episode of SH during the nine-year follow-up; 294 children experienced one episode, 115 two episodes and 97 three or more episodes of SH. HbA1c increased with episodes of SH and in the years following the first episode. The glycemic trajectory peaked 2 to 3 years after an SH episode. The accumulated deterioration in glycemic control was in the range of 5% in patients with two or more episodes equivalent to an increase in HbA1c of 4 mmol/mol (HbA1c ~0.4%).

CONCLUSION

SH was followed by a progressive and lasting increase in HbA1c among Danish children and adolescents with T1D. Thus, in addition to the known risk of new episodes of hypoglycemia and cognitive impairment, SH contributes to long-term diabetes complications.

A qualitative synthesis of the perceived factors that affect participation in physical activity among children and adolescents with type 1 diabetes

AIMS

To explore the qualitative literature on the perceived factors, positive and negative, affecting participation by children and adolescents with type 1 diabetes in physical activity, from the perspective of children and adolescents with type 1 diabetes, their family members, teachers or sports coaches, and healthcare professionals.

METHODS

MEDLINE, SPORTDiscus, PsycINFO, CINAHL and Scopus were systematically searched in July 2019. Eligible studies included any that reported qualitative findings on the perceived factors that affect participation in physical activity from either the perspective of children or adolescents with type 1 diabetes, their family members, teachers or coaches, and healthcare professionals.

RESULTS

The literature search yielded a total of 7859 studies, of which 14 (13 qualitative studies and one mixed-methods study) met the review inclusion criteria. In total there were 12 unique populations containing 270 individuals, 105 children or adolescents with type 1 diabetes,108 family members, 37 teachers and 20 healthcare professionals. The main factors thought to influence physical activity for this population were the individual characteristics of children and adolescents, the requirement for self-blood glucose regulation, support systems including friends, family, teachers and professionals, education and knowledge, and communication.

CONCLUSIONS

This review synthesizes views on the perceived factors from several different perspectives. The findings suggest that it is important to consider the needs of the wider support network, as well as the child's or adolescent's concerns and preferences, when developing new or existing strategies and programmes to promote physical activity in children and adolescents with type 1 diabetes.

Identifying sources of support and barriers to physical activity in pediatric type 1 diabetes

OBJECTIVES

Reports suggest that children with type 1 diabetes (T1D) perform less than the recommended daily activity and are less active than their non-diabetic peers. We aimed to: (a) Identify barriers and sources of support for exercise performance in pediatric T1D. (b) Identify strengths and limitations in the exercise-directed education provided by our diabetes team.

METHODS

Patients with T1D 5 to 20 years of age were recruited while attending a routine clinic visit. Participants completed a set of questionnaires assessing demographics, health data, barriers, and sources of support for exercise performance and diabetes related exercise education. The clinics' medical staff filled-out a questionnaire assessing the exercise-directed education provided in clinic.

RESULTS

Ninety-six subjects were included in this study, mean age 13.7 ± 3.8 years. Median weekly reported exercise time was 3.5 hours. The two most prevalent barriers were fear of hypoglycemia and low fitness, reported by 76% and 51%, respectively. Mean family and social support scores were 4.1 ± 0.7 and 3.3 ± 1.1, respectively (1-5 scale); the latter correlated with the amount of activity performed (cc = 0.360; P < .001). The majority of participants (97%) reported receiving guidance for physical activity, to their satisfaction. Yet, knowledge and implementation were suboptimal. All staff members reported conducting routine exercise-directed teaching, with variations in frequency and content.

CONCLUSIONS

Our findings suggest that in order to increase the amount of safely performed exercise in pediatric patients with T1D, fear of hypoglycemia must be addressed. Further efforts should focus on: (a) encouraging active family and social involvement (b) standardization of education.

Levels of Physical Activity in Children and Adolescents with Type 1 Diabetes in Relation to the Healthy Comparators and to the Method of Insulin Therapy Used

Given the fact that physical exertion leads to blood glucose fluctuations, type one diabetes mellitus (T1D) may potentially constitute a barrier for obtaining a sufficient amount of exercise. The main purpose of the study was to compare the level of physical activity between children with T1D (n = 215) and healthy controls (n = 115) and to assess the physical activity of the study group in relation to the applied method of insulin therapy, i.e., the use of insulin pen vs. insulin pump. The level of physical activity was assessed with a hip-worn tri-axial accelerometer (ActiGraph GT3X+) used by the subjects for an uninterrupted period of seven days. Children with T1D had significantly lower median values of total time of moderate (213.3 vs. 272.1 min), vigorous (135.3 vs. 19.6 min) and moderate-to-vigorous (347.4 vs. 467.4 min) physical activity compared to healthy peers respectively, (p < 0.001) in all cases. In addition, the total median number of steps was significantly lower (53,631 vs. 67,542 steps), (p < 0.001). The method of insulin therapy was not associated with significant differences in physical activity level (p > 0.001). The level of physical activity in children and adolescents with T1D is lower than in their healthy peers and does not depend on the insulin therapy method.

Sedentary behaviors in children and adolescents with type 1 diabetes, depending on the insulin therapy used

Assessment of sedentary behaviors in children and adolescents with type 1 diabetes (T1D), relative to the method of insulin therapy used, and in comparison to healthy controls.The study group consisted of 215 children with T1D, including 109 (50.7%) insulin pen and 106 (49.3%) insulqsain pump users. The control group comprised 115 healthy children. The subjects' sedentary time was measured with a tri-axial accelerometer ActiGraph GT3X+, used continuously for 7 days.The diabetes group was characterized by a significantly higher "% in sedentary time" score (P = .024) and a lower "mean daily breaks in sedentary time" result (P = .007), which means that they spent much more time on sedentary activities compared to the control group. There were no significant differences between the children using insulin pump and insulin pen in the "% in sedentary time" score (P = .294) and "mean daily breaks in sedentary time" (P = .251).The T1D is a serious encumbrance, leading to longer duration of sedentary time, in comparison to healthy controls. The type of insulin therapy did not significantly affect the percentage of the wear-day spent in sedentary time and mean daily breaks in sedentary time.

Individual glucose responses to prolonged moderate intensity aerobic exercise in adolescents with type 1 diabetes: The higher they start, the harder they fall

OBJECTIVE

To evaluate the pattern of change in blood glucose concentrations and hypoglycemia risk in response to prolonged aerobic exercise in adolescents with type 1 diabetes (T1D) that had a wide range in pre-exercise blood glucose concentrations.

METHODS

Individual blood glucose responses to prolonged (~60 minutes) moderate-intensity exercise were profiled in 120 youth with T1D.

RESULTS

The mean pre-exercise blood glucose concentration was 178 ± 66 mg/dL, ranging from 69 to 396 mg/dL, while the mean change in glucose during exercise was -76 ± 55 mg/dL (mean ± SD), ranging from +83 to -257 mg/dL. Only 4 of 120 youth (3%) had stable glucose levels during exercise (ie, ± ≤10 mg/dL), while 4 (3%) had a rise in glucose >10 mg/dL, and the remaining (93%) had a clinically significant drop (ie, >10 mg/dL). A total of 53 youth (44%) developed hypoglycemia (≤70 mg/dL) during exercise. The change in glucose was negatively correlated with the pre-exercise glucose concentration (R² = 0.44, P < 0.001), and tended to be greater in those on multiple daily insulin injections (MDI) vs continuous subcutaneous insulin infusion (CSII) (-98 ± 15 vs -65 ± 7 mg/dL, P = 0.05). No other collected variables appeared to predict the change in glucose including age, weight, height, body mass index, disease duration, daily insulin dose, HbA_1c , or sex.

CONCLUSION

Youth with T1D have variable glycemic responses to prolonged aerobic exercise, but this variability is partially explained by their pre-exercise blood glucose levels. When no implementation strategies are in place to limit the drop in glycemia, the incidence of exercise-associated hypoglycemia is ~44% and having a high pre-exercise blood glucose concentration is only marginally protective.

Basal fatty acid oxidation increases after recurrent low glucose in human primary astrocytes

AIMS/HYPOTHESIS

Hypoglycaemia is a major barrier to good glucose control in type 1 diabetes. Frequent hypoglycaemic episodes impair awareness of subsequent hypoglycaemic bouts. Neural changes underpinning awareness of hypoglycaemia are poorly defined and molecular mechanisms by which glial cells contribute to hypoglycaemia sensing and glucose counterregulation require further investigation. The aim of the current study was to examine whether, and by what mechanism, human primary astrocyte (HPA) function was altered by acute and recurrent low glucose (RLG).

METHODS

To test whether glia, specifically astrocytes, could detect changes in glucose, we utilised HPA and U373 astrocytoma cells and exposed them to RLG in vitro. This allowed measurement, with high specificity and sensitivity, of RLG-associated changes in cellular metabolism. We examined changes in protein phosphorylation/expression using western blotting. Metabolic function was assessed using a Seahorse extracellular flux analyser. Immunofluorescent imaging was used to examine cell morphology and enzymatic assays were used to measure lactate release, glycogen content, intracellular ATP and nucleotide ratios.

RESULTS

AMP-activated protein kinase (AMPK) was activated over a pathophysiologically relevant glucose concentration range. RLG produced an increased dependency on fatty acid oxidation for basal mitochondrial metabolism and exhibited hallmarks of mitochondrial stress, including increased proton leak and reduced coupling efficiency. Relative to glucose availability, lactate release increased during low glucose but this was not modified by RLG. Basal glucose uptake was not modified by RLG and glycogen levels were similar in control and RLG-treated cells. Mitochondrial adaptations to RLG were partially recovered by maintaining euglycaemic levels of glucose following RLG exposure.

CONCLUSIONS/INTERPRETATION

Taken together, these data indicate that HPA mitochondria are altered following RLG, with a metabolic switch towards increased fatty acid oxidation, suggesting glial adaptations to RLG involve altered mitochondrial metabolism that could contribute to defective glucose counterregulation to hypoglycaemia in diabetes.

Mini-Dose Glucagon as a Novel Approach to Prevent Exercise-Induced Hypoglycemia in Type 1 Diabetes

OBJECTIVE

Patients with type 1 diabetes who do aerobic exercise often experience a drop in blood glucose concentration that can result in hypoglycemia. Current approaches to prevent exercise-induced hypoglycemia include reduction in insulin dose or ingestion of carbohydrates, but these strategies may still result in hypoglycemia or hyperglycemia. We sought to determine whether mini-dose glucagon (MDG) given subcutaneously before exercise could prevent subsequent glucose lowering and to compare the glycemic response to current approaches for mitigating exercise-associated hypoglycemia.

RESEARCH DESIGN AND METHODS

We conducted a four-session, randomized crossover trial involving 15 adults with type 1 diabetes treated with continuous subcutaneous insulin infusion who exercised fasting in the morning at ∼55% VO_2max for 45 min under conditions of no intervention (control), 50% basal insulin reduction, 40-g oral glucose tablets, or 150-μg subcutaneous glucagon (MDG).

RESULTS

During exercise and early recovery from exercise, plasma glucose increased slightly with MDG compared with a decrease with control and insulin reduction and a greater increase with glucose tablets (P < 0.001). Insulin levels were not different among sessions, whereas glucagon increased with MDG administration (P < 0.001). Hypoglycemia (plasma glucose <70 mg/dL) was experienced by six subjects during control, five subjects during insulin reduction, and none with glucose tablets or MDG; five subjects experienced hyperglycemia (plasma glucose ≥250 mg/dL) with glucose tablets and one with MDG.

CONCLUSIONS

MDG may be more effective than insulin reduction for preventing exercise-induced hypoglycemia and may result in less postintervention hyperglycemia than ingestion of carbohydrate.

Management of diabetes mellitus in children and adolescents: engaging in physical activity

Regular physical activity is an important component in the management of both type 1 and type 2 diabetes mellitus (T1DM and T2DM), as it has the potential to improve glycemic control, delay cardiovascular complications, and increase overall well-being. Unfortunately, many children and adolescents with diabetes do not partake in regular exercise and physical activity for multiple reasons. This review identifies the barriers to participation from the aspect of the patient, caregiver, and the healthcare provider. The management of physical activity of children and adolescents with diabetes mellitus is unique and requires an understanding of exercise physiology and how it differs in these children and adolescents from those without the condition. These individuals are at risk for important and potentially life threatening complications including, but not limited to, severe or delayed nocturnal hypoglycemia. It is essential to identify these risks as well as, monitor and manage adjustments to carbohydrate intake and insulin dosing through basal-bolus regimen or insulin pump adjustments appropriately before, during, and after the exercise activity. This review discusses these issues and also outlines differences in management between patients with T1DM and T2DM.