Psychological motivation and patient education: a role for continuous glucose monitoring

Use of Personal Continuous Glucose Monitoring Device Is Associated With Reduced Risk of Hypoglycemia in a 16-Week Clinical Trial of People With Type 1 Diabetes Using Continuous Subcutaneous Insulin Infusion

AIMS

Continuous glucose monitoring (CGM) has the potential to promote diabetes self-management at home with a better glycemic control as outcome. Investigation of the effect of CGM has typically been carried out based on randomized controlled trials with prespecified CGM devices on CGM-naïve participants. The aim of this study was to investigate the effect on glycemic control in people using their personal CGM before and during the trial.

MATERIALS AND METHODS

Data from the Onset 5 trial of 472 people with type 1 diabetes using either their personal CGM (n = 117) or no CGM (n = 355) and continuous subcutaneous insulin infusion in a 16-week treatment period were extracted. Change from baseline in glycated hemoglobin A1c (HbA_1c), number of hypoglycemic episodes, and CGM metrics at the end of treatment were analyzed with analysis of variance repeated-measures models.

RESULTS

Use of personal CGM compared with no CGM was associated with a reduction in risk of documented symptomatic hypoglycemia (event rate ratio: 0.82; 95% CI: 0.69-0.97) and asymptomatic hypoglycemia (event rate ratio: 0.72; 95% CI: 0.53-0.97), reduced time spent in hypoglycemia (P = .0070), and less glycemic variability (P = .0043) without a statistically significant increase in HbA_1c (P = .2028).

CONCLUSIONS

Results indicate that use of personal CGM compared with no CGM in a population of type 1 diabetes is associated with a safer glycemic control without a statistically significantly deteriorated effect on HbA_1c, which adds to the evidence about the real-world use of CGM, where device type is not prespecified, and users are not CGM naïve.

Social Cognitive Theory in Diabetes Exercise Research: An Integrative Literature Review

PURPOSE

This integrative review critically examined the literature on diabetes research using Social Cognitive Theory (SCT) to determine its predictive ability in explaining exercise behavior and to identify key interventions that enhance exercise initiation and maintenance.

METHODS

Literature published between 1985 and 2002 was searched using the following keywords: SCT, self-efficacy, diabetes mellitus, non-insulin-dependent diabetes mellitus, insulin-dependent diabetes mellitus, physical activity, and exercise. The databases searched were CINAHL, Medline, and PsychInfo. Of the 38 articles retrieved from databases, 13 were reviewed.

RESULTS

A statistically significant relationship between self-efficacy and exercise behavior was found in correlational studies. Results from the predictive study support the predictability of self-efficacy for exercise behavior. Mixed results were found for the predictive ability of outcome expectancies for exercise behavior. Self-efficacy was predictive of exercise initiation and maintenance over time. The evidence for successful interventions to increase self-efficacy and exercise behavior over time was inconclusive.

CONCLUSIONS

To better understand exercise behavior and to develop effective exercise interventions, a microanalytic, theory-driven approach to studying exercise behavior is needed. Several suggestions are offered to strengthen exercise self-efficacy.

Salient characteristics of youth with type 1 diabetes initiating continuous glucose monitoring

OBJECTIVE

Consistent continuous glucose monitoring (CGM) use is a challenge in youth with type 1 diabetes. This study aimed to investigate patient and family behavioral and clinical characteristics associated with interest in implementing CGM.

RESEARCH DESIGN AND METHODS

In a cross-sectional study, we compared 120 youth interested in starting CGM (the CGM group) with a general sample of 238 youth with type 1 diabetes (the Standard group). Youth and their parents completed validated surveys assessing adherence to diabetes management, diabetes-specific family conflict, parent involvement in diabetes management, and youth quality of life. Demographic and clinical data were obtained from chart review and interview.

RESULTS

Youth participants had a mean age of 13.0±2.8 years, diabetes duration of 6.3±3.4 years, and hemoglobin A1c (HbA1c) level of 8.2±1.0% (66±11 mmol/mol). Youth in the CGM group performed more frequent blood glucose monitoring, had lower HbA1c levels, and were more likely to be treated by continuous subcutaneous insulin infusion (CSII) and to be living in two-parent homes than youth in the Standard group. Compared with the Standard group, youth interested in wearing a CGM device and their parents reported greater adherence to diabetes management, less diabetes-specific family conflict, and higher youth quality of life. No differences were found between groups with respect to parent involvement in diabetes management by both youth and parent reports.

CONCLUSIONS

In efforts to enhance CGM uptake, it is important to address factors such as blood glucose monitoring frequency, CSII use, adherence, and diabetes-specific family conflict when considering youth with type 1 diabetes for CGM implementation.

The effect of short-term use of the Guardian RT continuous glucose monitoring system on fear of hypoglycaemia in patients with type 1 diabetes mellitus

AIM

This study examines whether the short-term use of a continuous glucose monitor (CGM) can reduce the fear of hypoglycaemia in individuals with type 1 diabetes mellitus (T1DM).

METHODS

Twelve participants with T1DM were fitted with a Guardian® REAL-Time CGM and assigned to either an alarm (low glucose alarm set at 4.5 mmol/L) or no alarm condition for 3 days, with both treatments administered following a counterbalanced study design. The participants completed the Hypoglycaemia Fear Survey on three separate occasions, before their CGM was fitted as well as following the alarm and no alarm conditions.

RESULTS

The alarm treatment reduced the incidence of hypoglycaemic episodes (CGM readings≤3.5 mmol/L; 1.1±0.5 versus 1.9±0.5; mean±SEM) and the relative time spent below this hypoglycaemic threshold (0.9±0.4% versus 2.6±1.0%) but did not alter the fear of hypoglycaemia (78.6±7.0, 75.8±5.2 and 79.3±5.8 at baseline and following the alarm and no alarm treatments, respectively; p>0.05). CGM overestimated blood glucose levels by 0.8±0.2 mmol/L for blood glucose readings less than, or equal to, 5 mmol/L.

CONCLUSIONS

Short-term use of the Guardian® REAL-Time CGM has no clinically significant effect on fear of hypoglycaemia possibly due, in part, to the inaccuracies of CGMs at low blood glucose levels.

A review of current evidence with continuous glucose monitoring in patients with diabetes

Devices that measure glucose on a near-continuous basis may provide a better insight into glycemic profiles, allowing patients with diabetes to make therapeutic adjustments to improve metabolic control, thereby reducing the risk of diabetic complications. Motivated and technologically adept patients with brittle diabetes, hypoglycemia unawareness, diabetic pregnancy, or who use pumps might benefit.Current evidence of continuous glucose monitoring (CGM) on health outcome in patients with diabetes is critically reviewed. No data are available on chronic complications or mortality. Therefore, surrogate endpoints need to be investigated, particularly HbA1c, number of hypo- and hyperglycemic episodes, time within normal, high, or low glucose concentrations, glycemic variability, and quality of life.Randomized controlled trials (RCTs) using CGM in a retrospective way did not show metabolic improvement. In contrast, most RCTs applying real-time CGM showed a decrease in HbA1c, reduced glycemic variability, and a diminished number and length of hypo- and hyperglycemic events. Using accurate, real-time CGM devices improves quality of life by reducing the fear of unexpected hypoglycemic events. These beneficial effects were observed despite the fact that in most studies no clear treatment algorithm based on CGM results was provided to the patients. However, most trials were too short in duration, with a variable use of CGM, and were performed in small study samples.In conclusion, real-time CGM systems can improve metabolic control, reduce hypoglycemic episodes, and improve quality of life. Whether this holds true for longer time periods and in the majority of patients remains to be proven. In the long term, CGM might help to reduce chronic diabetes complications and perhaps also mortality, thereby reducing health care costs.

Psychological aspects of continuous glucose monitoring in pediatric type 1 diabetes

Clinical use of near-continuous glucose monitors (CGMs) could have substantial impact on family management of pediatric type 1 diabetes and could generate both beneficial and adverse psychological reactions. In addition to glycemic benefits, CGM could possibly yield educational and motivational benefits. Conversely, CGM may also lead to information overload and increased treatment burden. Further, patients and families with certain affective, behavioral, and cognitive characteristics might derive greater benefit from CGM use. As information about these processes could facilitate optimal clinical use of CGM, the Diabetes Research in Children Network (DirecNet) included measurement of selected psychological variables in a recent randomized trial of the GlucoWatch G2 Biographer (GW2B, Cyngus, Inc., Redwood City, CA, USA). A multicenter sample of 200 youths with type 1 diabetes was randomized to 6 months of either continued usual care (UC) using a conventional home glucose meter for diabetes or supplementation of standard care with use of the GW2B. Diabetes treatment adherence, diabetes-specific quality of life, and diabetes-related anxiety were measured at baseline and at the end of the study. Satisfaction with use of the GW2B was measured at the end of the study. The results indicated neither adverse nor beneficial psychological effects of CGM use. More frequent GW2B use over the 6-month study was found among youths whose parents reported higher scores for treatment adherence and diabetes-related quality of life at baseline. The study illustrates the empiric assessment of the psychological context of CGM use and establishes methods that are applicable to new CGM devices as they emerge.

The psychologic context of pediatric diabetes

During the past few decades, there has been an explosion of behavioral science research on family management of pediatric diabetes. This article distills the major conclusions from that literature, emphasizing how primary care providers can apply these findings in clinical practice.

Youth and parent satisfaction with clinical use of the GlucoWatch G2 Biographer in the management of pediatric type 1 diabetes

OBJECTIVE

A continuous glucose monitor satisfaction scale (CGM-SAT) was evaluated during a 6-month randomized controlled trial of the GlucoWatch G2 Biographer (GW2B) in youths with type 1 diabetes.

RESEARCH DESIGN AND METHODS

At the end of the 6-month trial, 97 parents and 66 older children who had been randomized to the GW2B group completed the CGM-SAT, which assesses satisfaction on 37 items using a five-point Likert scale. Descriptive analysis, calculation of several reliability estimates, and assessment of concurrent validity were performed.

RESULTS

The CGM-SAT demonstrated high internal reliability (Cronbach's alpha = 0.95 for parents and 0.94 for youths aged > or = 11 years), split-half reliability (rho = 0.91 for parents and 0.93 for youths), and parent-adolescent agreement (rho = 0.68, P < 0.001). Convergent validity was supported by marginally significant associations with treatment adherence and frequency of GW2B use. CGM-SAT scores did not correlate significantly with changes in treatment adherence, quality of life, or diabetes-related anxiety from baseline to 6 months. Mean scores on CGM-SAT items indicated that 81% of parental responses and 73% of youths' responses were less favorable than "neutral." Descriptive analysis indicated the GW2B requires substantial improvement before it can achieve widespread clinical utility and acceptance.

CONCLUSIONS

The results supported the psychometric properties of the CGM-SAT. The CGM-SAT warrants further research use and cross-validation with other continuous glucose monitors. This study provides a benchmark for comparison with new glucose sensors.

Improved metabolic control in diabetic adolescents using the continuous glucose monitoring system (CGMS)

OBJECTIVE

To determine the utility of the continuous glucose monitoring system (CGMS) as an outpatient procedure to improve management of diabetes in adolescents.

RESEARCH DESIGN AND METHODS

Twelve adolescents (mean age: 16.2 +/- 3 years) with poorly controlled type 1 diabetes (HbA(1c) > 8%) were included in this trial. Mean HbA(1c) during the previous year was 10.1 +/- 1.2%. Insulin treatment consisted of 2 or 3 daily injections in 10 cases and CSII in 2. At the beginning of the study, HbA(1c) was determined and low blood glucose index (LBGI) was calculated. Continuous glucose monitoring was performed for three days. After downloading and analyzing data, results were discussed with the patient and insulin treatment was adjusted. Two months later testing was repeated and all parameters were reassessed.

RESULTS

Initial CGMS profiles demonstrated glycemic excursions unrecognized by capillary measurements in all twelve patients. Glycemia before and after meals varied from<60 mg/dL to > 200 mg/dL in 2 patients (2 episodes). Postprandial hyperglycemia exceeded 200 mg/dL in 10 patients (24 episodes). Prolonged overnight hyperglycemia was observed in 5 patients (7 episodes), dawn phenomenon in 4 patients (6 episodes) and nighttime hypoglycemia in 4 patients (4 episodes). A day-to-day reproducibility of glycemic profiles was observed in 8 patients. Then insulin treatment was adjusted according to CGMS data. Changes involved dose levels in 3 patients, insulin type in 7, number of injections, i.e. 3 instead of 2, in 5 or change from insulin injection to CSII in 1. Reassessment two months later demonstrated a significant reduction of glycemic excursions in 8 patients. HbA(1c) (m +/- SD) decreased from 10.3 +/- 2.1% to 8.75 +/- 1.06% (p<0.05). LBGI increased from 1.7 +/- 0.9 to 2.4 +/- 1.4 but the difference was not significant.

CONCLUSIONS

Use of CGMS in diabetic adolescent outpatients achieved a significant improvement in metabolic control not only by providing accurate data for adjustment of insulin treatment but also by promoting patient communication and motivation.

Impact of pramlintide on glucose fluctuations and postprandial glucose, glucagon, and triglyceride excursions among patients with type 1 diabetes intensively treated with insulin pumps

OBJECTIVE

To assess the effects of adjunctive treatment with pramlintide, an analog of the beta-cell hormone amylin, on 24-h glucose fluctuations and postprandial glucose, glucagon, and triglyceride excursions in patients with type 1 diabetes intensively treated with continuous subcutaneous insulin infusion (CSII).

RESEARCH DESIGN AND METHODS

In this study, 18 patients (16 of whom could be evaluated) with type 1 diabetes (age 44 +/- 11 years, HbA(1c) 8.2 +/- 1.3% [mean +/- SD]) were given mealtime injections of 30 micro g pramlintide t.i.d. for 4 weeks in addition to their preexisting CSII regimen (16 lispro, 2 regular insulin). Mealtime insulin boluses were reduced by a minimum of 10% during the first 3 days, and re-adjusted thereafter based on clinical judgment. At weeks 0 (baseline), 4 (on treatment), and 6 (2 weeks off treatment), 24-h interstitial glucose concentrations were measured using a continuous glucose monitoring system (CGMS), and postprandial plasma glucose, glucagon, and triglyceride concentrations were measured in response to a standardized test meal.

RESULTS

At baseline, patients had excessive 24-h glucose fluctuations, with 59% of the CGMS measurements >140 mg/dl, 13% <80 mg/dl, and only 28% in the euglycemic range (80-140 mg/dl). After 4 weeks on pramlintide, measurements in the hyperglycemic range declined to 48% and measurements within the euglycemic range increased to 37%. This shift from the hyperglycemic to the euglycemic range occurred with a concomitant 17% reduction in mealtime insulin dosages and without relevant increases in measurements below the euglycemic range (15%) or any severe hypoglycemic events. After 4 weeks on pramlintide, postprandial glucose, glucagon, and triglyceride excursions were reduced by approximately 86, approximately 87, and approximately 72%, respectively (incremental areas under the curve, all P < 0.05 vs. baseline). At week 6 (off treatment), the 24-h glucose profile and postprandial glucose, glucagon, and triglyceride excursions approached pretreatment values.

CONCLUSIONS

In this study, the addition of pramlintide to insulin therapy reduced excessive 24-h glucose fluctuations as well as postprandial glucose, glucagon, and triglyceride excursions in patients with type 1 diabetes intensively treated with insulin pumps.