Standardized hospital management of pediatric diabetic ketoacidosis reduces frequency of low blood glucose episodes.

OBJECTIVE: In patients treated for DKA, decrease the rate of visits experiencing one or more BG < 80 mg/dl by 10% within 24 months. RESEARCH DESIGN AND METHODS: Plan-do-study-act cycles tested interventions linked to key drivers including: standardized DKA guidelines incorporating a two-bag fluid system, efficient ordering process, and care team education. Inclusion criterion: treatment for DKA with a bicarbonate value (HCO3 ) <15 mEq/L. PRIMARY OUTCOME: the percent of patient visits experiencing a BG < 80 mg/dl while undergoing treatment for DKA. Process measures included: order panel and order set utilization rates. Balancing measures included: emergency department and hospital lengths of stay, time to acidosis resolution (time to HCO3 ≥ 17 mEq/L), and admission rates. Outcomes were analyzed using statistical process control charts. RESULTS: From January 2017 through May 2021, our institution treated 288 different patients during 557 visits for suspected DKA. Following our interventions, the overall percent of patient visits for DKA with a BG < 80 mg/dl improved from 32% to 5%. The team did see small improvements in emergency department and hospital lengths of stay; otherwise, there was no significant change in our balancing measures. CONCLUSIONS: Use of quality improvement methodology and standardized DKA management resulted in a significant reduction of BG < 80 mg/dl in patients treated for DKA.

Measurement properties of Patient Reported Outcomes Measurement Information System domains for children with type 1 diabetes.

OBJECTIVE: Patient Reported Outcomes Measurement Information System (PROMIS) includes numerous domains to assess functioning among the pediatric population. These domains, however, have not been evaluated for use in children with type 1 diabetes (T1D). The objective of this study was to determine the measurement properties of PROMIS domains (pain behavior, pain quality, physical stress experience, physical activity, strength impact, and profile-25) in children with T1D. METHODS: This is a cross-sectional study of children with T1Drecruited from tertiary care facilities. To determine construct validity, we compared PROMIS T-scores between known-groups based on (a) glycemic control, hemoglobin A1c (HbA1c%) and (b) self-reported general health, using t test or analysis of variance. Reliability was determined using Cronbach's alpha and item response theory reliability. We also determined agreement between parent-proxy and child self-report PROMIS scores. RESULTS: Our study included 192 children, mean age 12.7 (SD = 2.9) years, eligible to self-report PROMIS surveys. There were significant differences in physical stress experience and pain intensity between children with HbA1c < 10% and those with HbA1c ≥ 10%. There also were significant differences in T-scores for all domains except physical function mobility and strength impact among children with poor/fair, good, very good/excellent general health. All valid domains had reliability >0.70. More than 40% of child-parent pairs were in agreement, with intraclass correlations coefficients (ICC) ranging between 0.41 and 0.63 for all domains, except pain behavior (%agreement = 23%; ICC = 0.29). CONCLUSIONS: Most of the PROMIS domains tested are valid, reliable, and able to differentiate children with T1D who report different general health states. There is moderate agreement between child-parent pairs for all domains except pain behavior.

Clinical associations of quarterly Patient Health Questionnaire-9 depression screening results in adolescents with type 1 diabetes.

BACKGROUND: Awareness of comorbid depression in type 1 diabetes (T1D) patients is necessary to optimize health and diabetes care. Depression can occur or recur requiring regular review for depression symptoms. A validated tool to screen adolescents for symptoms of depression is the Patient Health Questionnaire (PHQ)-9 Modified for Teens (PHQ91-9 ). METHODS: PHQ91-9 depression screen results, depression-related ICD-codes, demographic data, and information on complications and comorbidities of adolescents ≥11 years old with T1D were obtained. Longitudinal and single observation multivariable analyses identified associations of covariates with positive PHQ91-9 depression screens. RESULTS: 5032 PHQ91-9 surveys were completed by 1225 unique participants. Overall, 6% (286/5032) of the PHQ91-9 depression screens were positive, and 60% (171/286) of the positive screens occurred in 107 unique patients without documented depression. In the longitudinal analysis, positive PHQ91-9 screens were associated (P < .05) with a diagnosis of depression listed in the medical record (OR 9.8), diabetic retinopathy (OR 4.3), female sex (OR 1.9), and use of an insulin pump (OR 0.5), while the single observation analysis at the time of a positive PHQ91-9 indicated presence of depression in the medical record (odds ratio 12.1), female sex (OR 1.9), and obesity (OR 1.8) were significantly (P < .05) associated with positive PHQ91-9 results. CONCLUSION: Quarterly PHQ91-9 depression screening of adolescents with T1D during routine clinic visits can immediately inform care, and previous diagnosis of depression is the most strongly associated covariate, highlighting the importance of documenting depression in the medical record. Additionally, awareness for higher odds of positive PHQ91-9 depression screens in females, obese adolescent, and patients on insulin injections is important.

Impact of family-centered tailoring of pediatric diabetes self-management resources.

BACKGROUND: The American Diabetes Association recommends a family-centered approach that addresses each family's specific type 1 diabetes self-management barriers. OBJECTIVE: To assess an intervention that tailored delivery of self-management resources to families' specific self-management barriers. SUBJECTS: At two sites, 214 children 8-16 years old with type 1 diabetes and their parent(s) were randomized to receive tailored self-management resources (intervention, n = 106) or usual care (n = 108). METHODS: Our intervention (1) identified families' self-management barriers with a validated survey, (2) tailored self-management resources to identified barriers, and (3) delivered the resources as four group sessions coordinated with diabetes visits. Mixed effects models with repeated measures were fit to A1c as well as parent and child QOL during the intervention and 1 year thereafter. RESULTS: Participants were 44% youth (8-12 years) and 56% teens (13-16 years). No intervention effect on A1c or QOL was shown, combining data from sites and age groups. Analyzing results by site and age group, post-intervention A1c for teens at one site declined by 0.06 more per month for intervention teens compared to usual care (P < 0.05). In this group, post-intervention A1c declined significantly when baseline A1c was >8.5 (-0.08, P < 0.05), with an even larger decline when baseline A1c was >10 (-0.19, P < 0.05). In addition, for these teens, the significant improvements in A1c resulted from addressing barriers related to motivation to self-manage. Also at this site, mean QOL increased by 0.61 points per month more during the intervention for parents of intervention youth than for usual care youth (P < 0.05). CONCLUSIONS: Tailored self-management resources may improve outcomes among specific populations, suggesting the need to consider families' self-management barriers and patient characteristics before implementing self-management resources.

Design and baseline data from a PCORI-funded randomized controlled trial of family-centered tailoring of diabetes self-management resources.

This article describes the methodology, recruitment, participant characteristics, and sustained, intensive stakeholder engagement for Project ACE (Achieving control, Connecting resources, Empowering families). Project ACE is a randomized controlled trial of children and youth ages 8-16 with type 1 diabetes evaluating the impact of tailored self-management resources on hemoglobin A1c (A1c) and quality of life (QOL). Despite strong evidence that controlling A1c reduces long-term complications, <25% of US youth with type 1 diabetes meet A1c targets. Many interventions are efficacious in improving A1c and QOL for these youth, whose families often struggle with the substantial demands of the treatment regimen. However, most such interventions are ineffective in the real world due to lack of uptake by families and limited healthcare system resources. Project ACE is a multi-site trial designed to improve diabetes outcomes by tailoring existing, evidence-based interventions to meet families' needs and preferences. We hypothesize that this family-centered approach will result in better A1c and QOL than usual care. Project ACE has recruited and randomized 214 eligible 8-16year old youth and their parents. The 9-month intervention consisted of 4 group sessions tailored to families' self-management barriers as identified by a validated instrument. Outcomes including A1c and QOL for parents and youth will be assessed for 1year after the intervention. Stakeholder engagement was used to enhance this trial's recruitment, retention and integration into routine clinical care. Findings will inform implementation and dissemination of family-centered approaches to address self-management barriers. TRIAL REGISTRATION NUMBER: NCT02024750 Trial Registrar: Clinicaltrials.gov, https://clinicaltrials.gov/ct2/show/NCT02024750.

Optimal sampling intervals to assess long-term glycemic control using continuous glucose monitoring.

AIMS AND HYPOTHESIS: The optimal duration and frequency of short-term continuous glucose monitoring (CGM) to reflect long-term glycemia have not been determined. The Juvenile Diabetes Research Foundation CGM randomized trials provided a large dataset of longitudinal CGM data for this type of analysis. METHODS: The analysis included 185 subjects who had 334 3-month intervals of CGM data meeting specific criteria. For various glucose indices, correlations (r²) were computed for the entire 3-month interval versus selected sampling periods ranging from 3 to 15 days. Other computed agreement measures included median relative absolute difference, values within ± 10% and ± 20% of full value, and median absolute difference. RESULTS: As would be expected, the more days of glucose data that were sampled, the higher the correlation with the full 3 months of data. For 3 days of sampling, the r² value ranged from 0.32 to 0.47, evaluating mean glucose, percentage of values 71-180 mg/dL, percentage of values > 180 mg/dL, percentage of values ≤ 70 mg/dL, and coefficient of variation; in contrast, for 15 days of sampling, the r² values ranged from 0.66 to 0.75. The results were similar when the analysis intervals were stratified by age group (8-14, 15-24, and ≥ 25 years), by baseline hemoglobin A1c level (< 7.0% and ≥ 7.0%), and by CGM device type. CONCLUSIONS AND INTERPRETATION: Our data suggest that a 12-15-day period of monitoring every 3 months may be needed to optimally assess overall glucose control. Shorter periods of sampling can be useful, but the correlation with 3-month measures of glycemic control is lower.

Factors predictive of severe hypoglycemia in type 1 diabetes: analysis from the Juvenile Diabetes Research Foundation continuous glucose monitoring randomized control trial dataset.

OBJECTIVE: Identify factors predictive of severe hypoglycemia (SH) and assess the clinical utility of continuous glucose monitoring (CGM) to warn of impending SH. RESEARCH DESIGN AND METHODS: In a multicenter randomized clinical trial, 436 children and adults with type 1 diabetes were randomized to a treatment group that used CGM (N = 224), or a control group that used standard home blood glucose monitoring (N = 212) and completed 12 months of follow-up. After 6 months, the original control group initiated CGM while the treatment group continued use of CGM for 6 months. Baseline risk factors for SH were evaluated over 12 months of follow-up using proportional hazards regression. CGM-derived indices of hypoglycemia were used to predict episodes of SH over a 24-h time horizon. RESULTS: The SH rate was 17.9 per 100 person-years, and a higher rate was associated with the occurrence of SH in the prior 6 months and female sex. SH frequency increased eightfold when 30% of CGM values were ≤ 70 mg/dL on the prior day (4.5 vs. 0.5%; P < 0.001), but the positive predictive value (PPV) was low (<5%). Results were similar for hypoglycemic area under the curve and the low blood glucose index calculated by CGM. CONCLUSIONS: SH in the 6 months prior to the study was the strongest predictor of SH during the study. CGM-measured hypoglycemia over a 24-h span is highly associated with SH the following day (P < 0.001), but the PPV is low.

Preventing post-exercise nocturnal hypoglycemia in children with type 1 diabetes.

OBJECTIVE: To determine the effects of reducing overnight basal insulin or a bedtime dose of terbutaline on nocturnal blood glucose (BG) nadir and hypoglycemia after exercise in children with type 1 diabetes mellitus. STUDY DESIGN: Sixteen youth (mean age 13.3 years) on insulin pumps were studied overnight on 3 occasions after a 60-minute exercise session with BG measurements every 30 minutes. Admissions were randomized to bedtime treatment with oral terbutaline 2.5 mg, 20% basal rate insulin reduction for 6 hours, or no treatment. RESULTS: Mean overnight nadir BG was 188 mg/dL after terbutaline and 172 mg/dL with basal rate reduction compared with 127 mg/dL on the control night (P = .002 and .042, respectively). Terbutaline eliminated nocturnal hypoglycemia but resulted in significantly more hyperglycemia (≥250 mg/dL) when compared with the control visit (P < .0001). The basal rate reduction resulted in fewer BG readings <80 and <70 mg/dL but more readings ≥250 mg/dL when compared with the control visit. CONCLUSIONS: A basal insulin rate reduction was safe and effective in raising post-exercise nocturnal BG nadir and in reducing hypoglycemia in children with type 1 diabetes mellitus. Although effective at preventing hypoglycemia, a 2.5-mg dose of terbutaline was associated with hyperglycemia.

Blunted counterregulatory hormone responses to hypoglycemia in young children and adolescents with well-controlled type 1 diabetes.

OBJECTIVE: Hypoglycemia in young children with type 1 diabetes is an acute complication of intensive insulin therapy and is commonly observed in the absence of signs or symptoms. The effect of intensive treatment and patient age on sympathoadrenal responses has not been established in youth with type 1 diabetes because of difficulties in testing procedures. RESEARCH DESIGN AND METHODS: We developed a standardized inpatient continuous subcutaneous insulin infusion protocol to produce a progressive fall in plasma glucose concentrations in insulin pump-treated patients. Plasma glucose and counterregulatory hormone concentrations were measured in 14 young children (3 to <8 years, A1C 7.7 +/- 0.6%) vs. 14 adolescents (12 to <18 years, A1C 7.6 +/- 0.8%). RESULTS: Plasma glucose decreased to similar nadir concentrations in the two groups. Four young children and four adolescents never had an epinephrine response. In the four young children and five adolescents who had a modest epinephrine response, this only occurred when plasma glucose fell to <60 mg/dl. In evaluating symptom scores, 29% of parents of young children felt that their child looked hypoglycemic, even at the lowest plasma glucose concentrations. Adolescents were better able to detect symptoms of hypoglycemia. In comparison with our data, epinephrine response to hypoglycemia in 14 nondiabetic adolescents studied at the Children's Hospital of Pittsburgh was higher. CONCLUSIONS: These data suggest that even young children and adolescents with type 1 diabetes are prone to develop hypoglycemia-associated autonomic failure regardless of duration. Whether these abnormalities can be reversed using continuous glucose monitoring and closed-loop insulin delivery systems awaits further study.

Continuous glucose monitoring in youth with type 1 diabetes.

Continuous glucose monitoring (CGM) is becoming increasingly popular and represents the third era of diabetes management. Currently available CGM devices have been studied in youth with type 1 diabetes and show similar accuracy across all age groups. Tolerability of these devices relates to alarm settings, sensor skin irritation, and durability of the device. Youth will be most successful on a CGM regimen if they have a personal investment in wearing the CGM device and have a stable support system for their diabetes care. Data indicate that glycemic control improves the most in youth who wear CGM devices >or=5 days per week, allowing for the ability to make more insulin dose changes. CGM has proven useful in alerting youth to hypoglycemia and may be a valuable tool with exercise. Further studies are needed to assess the utility of CGM for prevention of severe hypoglycemic events and increasing time spent in euglycemia. Fear of hypoglycemia may be ameliorated with CGM use; however, the potential for increased stress in families with continuous feedback must also be considered. In the future, CGM use in youth may couple with insulin pump technology to create a "closed-loop" system in which the CGM device will direct insulin administration without user input.

The effect of continuous glucose monitoring in well-controlled type 1 diabetes.

OBJECTIVE The potential benefits of continuous glucose monitoring (CGM) in the management of adults and children with well-controlled type 1 diabetes have not been examined. RESEARCH DESIGN AND METHODS A total of 129 adults and children with intensively treated type 1 diabetes (age range 8-69 years) and A1C <7.0% were randomly assigned to either continuous or standard glucose monitoring for 26 weeks. The main study outcomes were time with glucose level < or =70 mg/dl, A1C level, and severe hypoglycemic events. RESULTS At 26 weeks, biochemical hypoglycemia (< or =70 mg/dl) was less frequent in the CGM group than in the control group (median 54 vs. 91 min/day), but the difference was not statistically significant (P = 0.16). Median time with a glucose level < or =60 mg/dl was 18 versus 35 min/day, respectively (P = 0.05). Time out of range (< or =70 or >180 mg/dl) was significantly lower in the CGM group than in the control group (377 vs. 491 min/day, P = 0.003). There was a significant treatment group difference favoring the CGM group in mean A1C at 26 weeks adjusted for baseline (P < 0.001). One or more severe hypoglycemic events occurred in 10 and 11% of the two groups, respectively (P = 1.0). Four outcome measures combining A1C and hypoglycemia data favored the CGM group in comparison with the control group (P < 0.001, 0.007, 0.005, and 0.003). CONCLUSIONS Most outcomes, including those combining A1C and hypoglycemia, favored the CGM group. The weight of evidence suggests that CGM is beneficial for individuals with type 1 diabetes who have already achieved excellent control with A1C <7.0%.

Prolonged use of continuous glucose monitors in children with type 1 diabetes on continuous subcutaneous insulin infusion or intensive multiple-daily injection therapy.

OBJECTIVE: For continuous glucose sensors to improve the treatment of children with type 1 diabetes (T1D), they must be accurate, comfortable to wear, and easy to use. We conducted a pilot study of the FreeStyle Navigator Continuous Glucose Monitoring System (Abbott Diabetes Care) to examine the feasibility of daily use of a continuous glucose monitor (CGM) in an extended ambulatory setting. METHODS: Following a 13-wk trial of daily Navigator use, 45 children with T1D [10.7 +/- 3.7 yr, range 4.6-17.6, 24 using insulin pumps; continuous subcutaneous insulin infusion (CSII) and 21 using glargine-based multiple daily injections (MDI)] used the Navigator for an additional 13 wk. RESULTS: Navigator use was initially slightly higher in the CSII users than in the MDI users but declined similarly in both groups by 22-26 wk. After 26 wk, 11 (46%) of 24 CSII users and 7 (33%) of 21 MDI users were using the CGM at least 5 d a week. No baseline demographic or clinical factors were predictive of the amount of sensor use at 26 wk. However, Navigator use during weeks 1-13 and scores on a CGM satisfaction survey at 13 wk were predictive of use in weeks 22-26. CONCLUSIONS: CGM was generally well-tolerated in children with T1D for more than 6 months, and early acceptance of CGM was predictive of extended use of the device. Although many subjects and parents found CGM valuable, the declining usage over time underscores the need to develop new technologies and strategies to increase acceptance, effectiveness, and long-term use of these devices in youth with T1D.

Continuous glucose monitoring and intensive treatment of type 1 diabetes.

BACKGROUND: The value of continuous glucose monitoring in the management of type 1 diabetes mellitus has not been determined. METHODS: In a multicenter clinical trial, we randomly assigned 322 adults and children who were already receiving intensive therapy for type 1 diabetes to a group with continuous glucose monitoring or to a control group performing home monitoring with a blood glucose meter. All the patients were stratified into three groups according to age and had a glycated hemoglobin level of 7.0 to 10.0%. The primary outcome was the change in the glycated hemoglobin level at 26 weeks. RESULTS: The changes in glycated hemoglobin levels in the two study groups varied markedly according to age group (P=0.003), with a significant difference among patients 25 years of age or older that favored the continuous-monitoring group (mean difference in change, -0.53%; 95% confidence interval [CI], -0.71 to -0.35; P<0.001). The between-group difference was not significant among those who were 15 to 24 years of age (mean difference, 0.08; 95% CI, -0.17 to 0.33; P=0.52) or among those who were 8 to 14 years of age (mean difference, -0.13; 95% CI, -0.38 to 0.11; P=0.29). Secondary glycated hemoglobin outcomes were better in the continuous-monitoring group than in the control group among the oldest and youngest patients but not among those who were 15 to 24 years of age. The use of continuous glucose monitoring averaged 6.0 or more days per week for 83% of patients 25 years of age or older, 30% of those 15 to 24 years of age, and 50% of those 8 to 14 years of age. The rate of severe hypoglycemia was low and did not differ between the two study groups; however, the trial was not powered to detect such a difference. CONCLUSIONS: Continuous glucose monitoring can be associated with improved glycemic control in adults with type 1 diabetes. Further work is needed to identify barriers to effectiveness of continuous monitoring in children and adolescents. (ClinicalTrials.gov number, NCT00406133.)

Use of the DirecNet Applied Treatment Algorithm (DATA) for diabetes management with a real-time continuous glucose monitor (the FreeStyle Navigator).

BACKGROUND: There are no published guidelines for use of real-time continuous glucose monitoring data by a patient; we therefore developed the DirecNet Applied Treatment Algorithm (DATA). The DATA provides algorithms for making diabetes management decisions using glucose values: (i) in real time which include the direction and rate of change of glucose levels, and (ii) retrospectively based on downloaded sensor data. OBJECTIVE: To evaluate the use and effectiveness of the DATA in children with diabetes using a real-time continuous glucose sensor (the FreeStyle Navigator). SUBJECTS: Thirty children and adolescents (mean +/- standard deviation age = 11.2 +/- 4.1 yr) receiving insulin pump therapy. METHODS: Subjects were instructed on use of the DATA and were asked to download their Navigator weekly to review glucose patterns. An Algorithm Satisfaction Questionnaire was completed at 3, 7, and 13 wk. RESULTS: At 13 wk, all of the subjects and all but one parent thought that the DATA gave good, clear directions for insulin dosing, and thought the guidelines improved their postprandial glucose levels. In responding to alarms, 86% of patients used the DATA at least 50% of the time at 3 wk, and 59% reported doing so at 13 wk. Similar results were seen in using the DATA to adjust premeal bolus doses of insulin. CONCLUSIONS: These results show the feasibility of implementing the DATA when real-time continuous glucose monitoring is initiated and support its use in future clinical trials of real-time continuous glucose monitoring.

Recent advances in insulin treatment of children.

Since the findings of the Diabetes Control and Complications Trial became public in 1993, intensive insulin therapy has been recommended for all children. However, successful implementation remains a challenge because of developmental, physiological and cultural, as well as practical issues specific to the pediatric population. This article reviews the different insulin regimens that are currently available, from the short- and intermediate-acting insulins to the newer insulin analogs, focusing on insulin therapies that attempt to provide a more physiologic basal-bolus approach to treatment. More and more children are on multiple daily injection regimens or using continuous subcutaneous insulin infusion to achieve better metabolic control. The achievement of optimal glycemic control in children is complicated by their variability in eating habits and activity levels and perhaps more importantly by the risk of hypoglycemia. The hope is that new technologies including continuous subcutaneous glucose monitoring and perhaps a closed-loop system in the near future will help us achieve more optimal glycemic targets in children without increased side effects. In addition, continuous glucose monitoring may teach us better ways to use insulin in children who do not have the technology available to them.

Continuous glucose monitoring in children with type 1 diabetes.

OBJECTIVE: To examine the feasibility of daily use of a continuous glucose monitor, the FreeStyle Navigator Continuous Glucose Monitoring System ("Navigator"), in children with type 1 diabetes (T1D). STUDY DESIGN: After a masked Navigator was used for 4 to 7 days to establish a baseline level of glycemic control, 30 insulin pump users with T1D (average age 11.2 years) were asked to use the Navigator daily for 13 weeks. RESULTS: Subjects averaged 149 h/wk of Navigator use during the first 4 weeks, which decreased slightly to 134 h/wk during weeks 9 to 13 (P = .006). Mean hemoglobin A1c improved from 7.1% at baseline to 6.8% at 13 weeks (P = .02), and the percentage of glucose values between 71 and 180 mg/dL increased from 52% to 60% (P = .01). Subjects and parents reported high satisfaction with the Navigator on the Continuous Glucose Monitor Satisfaction Scale. Two subjects had severe skin reactions related to sensor mount adhesive. CONCLUSION: This study indicates that incorporating real-time continuous glucose monitoring into the daily treatment of children with T1D is feasible. The results provide a compelling rationale for conducting a randomized trial of daily use of a continuous glucose monitor in children with T1D.

Prevention of hypoglycemia during exercise in children with type 1 diabetes by suspending basal insulin.

OBJECTIVE: Strategies for preventing hypoglycemia during exercise in children with type 1 diabetes have not been well studied. The Diabetes Research in Children Network (DirecNet) Study Group conducted a study to determine whether stopping basal insulin could reduce the frequency of hypoglycemia occurring during exercise. RESEARCH DESIGN AND METHODS: Using a randomized crossover design, 49 children 8-17 years of age with type 1 diabetes on insulin pump therapy were studied during structured exercise sessions on 2 days. On day 1, basal insulin was stopped during exercise, and on day 2 it was continued. Each exercise session, performed from approximately 4:00-5:00 p.m., consisted of four 15-min treadmill cycles at a target heart rate of 140 bpm (interspersed with three 5-min rest breaks over 75 min), followed by a 45-min observation period. Frequently sampled glucose concentrations (measured in the DirecNet Central Laboratory) were measured before, during, and after the exercise. RESULTS: Hypoglycemia (< or = 70 mg/dl) during exercise occurred less frequently when the basal insulin was discontinued than when it was continued (16 vs. 43%; P = 0.003). Hyperglycemia (increase from baseline of > or = 20% to > or = 200 mg/dl) 45 min after the completion of exercise was more frequent without basal insulin (27 vs. 4%; P = 0.002). There were no cases of abnormal blood ketone levels. CONCLUSIONS: Discontinuing basal insulin during exercise is an effective strategy for reducing hypoglycemia in children with type 1 diabetes, but the risk of hyperglycemia is increased.

Evaluation of factors affecting CGMS calibration.

BACKGROUND: The optimal number/timing of calibrations entered into the CGMS (Medtronic MiniMed, Northridge, CA) continuous glucose monitoring system have not been previously described. METHODS: Fifty subjects with Type 1 diabetes mellitus (10-18 years old) were hospitalized in a clinical research center for approximately 24 h on two separate days. CGMS and OneTouch Ultra meter (LifeScan, Milpitas, CA) data were obtained. The CGMS was retrospectively recalibrated using the Ultra data varying the number and timing of calibrations. Resulting CGMS values were compared against laboratory reference values. RESULTS: There was a modest improvement in accuracy with increasing number of calibrations. The median relative absolute deviation (RAD) was 14%, 15%, 13%, and 13% when using three, four, five, and seven calibration values, respectively (P < 0.001). Corresponding percentages of CGMS-reference pairs meeting the International Organisation for Standardisation criteria were 66%, 67%, 71%, and 72% (P < 0.001). Nighttime accuracy improved when daytime calibrations (pre-lunch and pre-dinner) were removed leaving only two calibrations at 9 p.m. and 6 a.m. (median difference, -2 vs. -9 mg/dL, P < 0.001; median RAD, 12% vs. 15%, P = 0.001). Accuracy was better on visits where the average absolute rate of glucose change at the times of calibration was lower. On visits with average absolute rates <0.5, 0.5 to <1.0, 1.0 to <1.5, and >or=1.5 mg/dL/min, median RAD values were 13% versus 14% versus 17% versus 19%, respectively (P = 0.05). CONCLUSIONS: Although accuracy is slightly improved with more calibrations, the timing of the calibrations appears more important. Modifying the algorithm to put less weight on daytime calibrations for nighttime values and calibrating during times of relative glucose stability may have greater impact on accuracy.

Mixing rapid-acting insulin analogues with insulin glargine in children with type 1 diabetes mellitus.

OBJECTIVE: To determine whether mixing insulin glargine (IG) with a rapid-acting insulin (RAI) analogue in the same syringe had any deleterious effects on glycemic control in children with type 1 diabetes mellitus. STUDY DESIGN: Data from 55 children mixing the IG with a RAI analogue was collected for 6 months before and 6 months after the insulin mixing began. Data from a control group of 55 children not mixing the insulins was collected at similar intervals. Parameters evaluated included hemoglobin A1c (HbA1c) values, number of non-severe and severe hypoglycemic events, number of diabetic ketoacidosis (DKA) events, and blood glucose distribution patterns. RESULTS: After 6 months of study, HbA1c values were equivalent for the control and test groups (8.54+/-1.14 vs 8.61+/-1.14, respectively; P=1.0000). Percentages of blood glucose values in, above, and below the target range did not vary significantly in the groups. There were no significant differences in the groups in the occurrence of non-severe or severe hypoglycemic events or of DKA events. CONCLUSION: There were no significant differences in glycemic control between children who mixed IG in the same syringe with a RAI analogue compared with children who took separate injections.