A randomized multicenter trial comparing the GlucoWatch Biographer with standard glucose monitoring in children with type 1 diabetes

OBJECTIVE

This study assesses whether use of the GlucoWatch G2 Biographer (GW2B) in addition to standard glucose monitoring lowers HbA(1c) and reduces hypoglycemia compared with standard glucose monitoring alone.

RESEARCH DESIGN AND METHODS

In all, 200 subjects aged 7 to <18 years with type 1 diabetes were randomly assigned at five centers to standard glucose monitoring (usual care) or standard glucose monitoring plus GW2B use for 6 months. Study outcomes included HbA(1c) values obtained at 6 months and occurrence of severe hypoglycemia.

RESULTS

The mean HbA(1c) at baseline was 8.0% in both groups; at 6 months, HbA(1c) was 7.9% in the usual care group and 8.1% in the GW2B group (95% CI for mean reduction in the GW2B group compared with the usual care group -0.4 to 0.1%; P = 0.15). A decrease in HbA(1c) of > or =0.5% was achieved in 21% of the usual care group and 28% of the GW2B group (P = 0.29). Severe hypoglycemia events occurred in 7% of the GW2B group and in 2% of the usual care group (P = 0.10). In the GW2B group, sensor use declined throughout the study from a mean value of 2.1 times/week in the 1st month to 1.5 times/week in the 6th month. Reasons given for declining use included skin irritation (76%), frequent skips (56%), excessive alarms (47%), and inaccurate readings (33%).

CONCLUSIONS

Use of the GW2B in addition to standard glucose monitoring did not improve glycemic control or reduce the frequency of severe hypoglycemia. Skin reactions and other problems led to decreasing sensor use over time.

Parents' Reflections on Managing Their Children's Diabetes With Insulin Pumps

PURPOSE

To describe the experiences of parents managing the type 1 diabetes of their young children using an insulin pump.

DESIGN

Qualitative description, based on principles of naturalistic inquiry.

METHODS

Open-ended, in-depth interviews were conducted with 21 mothers and fathers of 16 children less than 12 years old in the eastern part of the United States. The children had been on pump treatment from 3 to 36 months. Data were managed and analyzed using qualitative content analysis.

FINDINGS

Parents reported becoming comfortable with pump management 10 days to 2-3 months after the child started using it. During this adjustment period, they had to "rethink" how they managed the disease. Although using the pump required vigilance and more frequent glucose checking than did multiple daily injections (MDI), the pump provided better glucose control, easier disease management, fewer variables to manipulate, and more flexible meal times. A few parents were tempted to more tightly control the child's glucose levels, which could potentially increase parental stress. Fathers were actively involved in the day-to-day management and benefited from opportunities to participate in the child's care. They emphasized the importance of practicing the tasks associated with diabetes management to improve their confidence when caring for the child alone. Parents reported that everyone in the family experienced more freedom, flexibility, and spontaneity in their daily lives.

CONCLUSIONS

For this sample of parents, the health and management benefits of their children's use of the insulin pump outweighed the adjustment challenges involved in changing from MDI.

GlucoWatch G2 Biographer alarm reliability during hypoglycemia in children

BACKGROUND

The GlucoWatch G2 Biographer (GW2B) (Cygnus, Inc., Redwood City, CA) provides near-continuous monitoring of glucose values in near real time. This device is equipped with two types of alarms to detect hypoglycemia. The hypoglycemia alarm is triggered when the current glucose measurement falls below the level set by the user. The "down alert" alarm is triggered when extrapolation of the current glucose trend anticipates hypoglycemia to occur within the next 20 min.

METHODS

We used data from an inpatient accuracy study to assess the performance of these alarms. During a 24-h clinical research center stay, 89 children and adolescents with Type 1 diabetes mellitus (3.5-17.7 years old) wore 174 GW2B devices and had frequent serum glucose determinations during the day and night.

RESULTS

Sensitivity to detect hypoglycemia (reference glucose < or = 60 mg/dL) during an insulin-induced hypoglycemia test was 24% with the hypoglycemia alarm alone and 88% when combined with the down alert alarm. Overnight sensitivity from 11 p.m. to 6 a.m. was 23% with the hypoglycemia alarm alone and 77% when combined with the down alert alarm. For 16% of hypoglycemia alarms, the reference glucose was above 70 mg/dL for 30 min before and after the time of the alarm. For the two alarm types combined, the corresponding false-positive rate increased to 62%.

CONCLUSIONS

The down alert alarm substantially improves the sensitivity of the GW2B to detect hypoglycemia at the price of a large increase in the false alarm rate. The utility of these alarms in the day-to-day management of children with diabetes remains to be determined.

Constant vigilance: mothers' work parenting young children with type 1 diabetes

Little is known about the experiences of mothers raising young children with type 1 diabetes. The purpose of this study was to describe the day-to-day experiences of mothers (N = 28) raising young children under 4 years of age with type 1 diabetes. Descriptive, naturalistic inquiry principles were used to interview subjects, as well as to manage and analyze the data. The mothers reported using the management behavior of constant vigilance. Their concerns about hypoglycemia and providing competent care reflected the interplay between their fears and profound sense of responsibility for managing the disease. Mothers reported having to learn the management behaviors and to occasionally adjust the day-to-day management when either severe hypoglycemia or developmental milestones occurred. Although mothers initially had feelings of incompetence with the care they provided, with time, they became very skilled. There were also reports of limited access to babysitting, child care, or respite services. The intensity of their constant vigilance associated with their concerns, responsibility, and lack of supports resulted in some mothers having physical and/or emotional problems. The findings of the study highlight the importance of identifying family and/or community resources that may provide mothers with support that could reduce some of the tremendous stress and burden of responsibility experienced after diagnosis of diabetes.

Depression in type 1 diabetes in children: natural history and correlates

The combination of diabetes and depression in children and adolescents is largely unstudied. The purpose of this article is to review the literature on the natural history and correlates of comorbid diabetes and depression in children and adolescents. Children with diabetes have a two-fold greater prevalence of depression, and adolescents up to three-fold greater, than youth without diabetes. Correlates of depression and diabetes include gender, poorer metabolic control, and family behaviors. Very little is known about treatment in these youth, and more studies are indicated.

Mothers' experiences raising young children with type 1 diabetes

ISSUES AND PURPOSE

To examine the day-to-day experiences of mothers raising children 4 years of age and younger with type 1 diabetes.

DESIGN AND METHODS

The descriptive design compared mothers of children with (n = 25) and without diabetes (n = 25). Mother-child observations were completed for children with diabetes.

RESULTS

Mothers of children with diabetes are very skilled in reading their children's behavioral cues. Mothers' concerns included the fear of hypoglycemia and seizure activity, access to daycare centers, and babysitting services capable of caring for their children's condition. These responses significantly differed from the control group mothers.

PRACTICE IMPLICATIONS

Nurses can affirm that hypoglycemia-related fears are normal and help mothers identify community resources that might ease the burden of care required, especially during the early postdiagnosis period.

Elevated ambulatory blood pressure in 20 subjects with Williams syndrome

Previous studies report conflicting frequencies of hypertension in cohorts of patients with Williams syndrome (WS). We studied blood pressure (BP) in WS using 24-hour ambulatory BP monitoring. This technique reliably measures day- and nighttime BP in a subject's natural environment and provides better prognostic information on long-term risks of hypertension than casual BP determinations. Twenty WS subjects evaluated through a multidisciplinary WS clinic and 35 age and gender-matched controls were studied. We found that WS subjects had significantly higher ambulatory BP than controls. After controlling for age, sex, and weight, the diagnosis of WS added approximately 10 mmHg to mean daytime and nighttime BPs. Hypertension, as defined by elevated mean daytime BP, was present in 40% of WS subjects versus 14% of controls (P < 0.05); among the children studied this difference was even more dramatic with 46% of WS children versus 6% of control children classified as hypertensive (P = 0.01). We also demonstrated normal diurnal BP variation but no evidence of a "white coat" effect or increased BP variability. Interestingly, parental reporting of a history of infantile hypercalcemia was strongly associated with the presence of hypertension (P = 0.008). Our data demonstrate that both children and adults with WS have higher mean BP and higher frequency of hypertension than healthy controls. Thus, elevated BP readings in the office setting should not be dismissed but require more thorough assessment.

Coronary artery disease in diabetic pregnancies

Severe vascular complications of diabetes mellitus include myocardial infarction and when this occurs during pregnancy it is associated with a high risk of maternal mortality. In the absence of myocardial infarction, information is unavailable on pregnancy outcome in diabetic patients with severe coronary artery disease or with prior coronary artery bypass graft. Such a case is presented together with a review of the literature.

Effect of growth hormone on oral glucose tolerance and circulating metabolic fuels in man

We infused growth hormone into normal subjects in doses that raised circulating hormone to levels (30-35 ng/ml) similar to those seen during stress. Growth hormone excess failed to alter fasting glucose and somatomedin concentrations. However, non-esterified fatty acids and ketones increased by 50% (p less than 0.05) and 120% (p less than 0.01), respectively, despite 35% higher plasma insulin concentrations. When oral glucose was ingested 5 h after initiating the growth hormone infusion, plasma glucose rose by 2-2.5 mmol/l above control (saline infusion) values and the area under the glucose curve increased twofold (p less than 0.005). This occurred in the face of twofold higher insulin levels and normal suppression of glucagon. Growth hormone also did not affect the hyperglycaemic response to a combined infusion of cortisol, glucagon and adrenaline, but accentuated the rise in non-esterified fatty acids, ketones, and insulin caused by these hormones. Our data suggest that growth hormone excess rapidly produces insulin antagonistic effects that may contribute to stress-induced glucose intolerance and lipolysis, even though fasting glucose levels remain unchanged.

Insulin binding and insulin sensitivity in isolated growth hormone deficiency

125I-insulin binding to monocytes was examined in five children and one adult with isolated growth hormone deficiency before and after three to 12 weeks of growth hormone treatment, and in eight controls. Before treatment, mean plasma glucose was 15 mg per deciliter below controls, and plasma insulin was reduced by 40 per cent. Insulin binding to monocytes was 70 per cent greater than controls (P less than 0.005). Insulin-mediated glucose uptake (determined in the adult patient) was 25 per cent greater than mean control levels. After treatment, plasma glucose rose to control levels, plasma insulin increased to 75 per cent above controls (P less than 0.01), and insulin binding fell to 50 per cent below controls (P less than 0.01). Insulin-mediated glucose uptake fell to 30 per cent below the mean control rate. Insulin binding increases in growth hormone deficiency and falls after treatment. These changes may contribute to alterations in insulin sensitivity accompanying altered growth hormone availability.

Influence of glucagon replacement on the hyperglycemic and hyperketonemic response to prolonged somatostatin infusion in normal man

Somatostatin was infused for 6 h into seven normal subjects with and without a replacement dose of glucagon. The addition of glucagon to somatostatin resulted in a 30-40% rise in plasma glucagon, whereas plasma insulin declined by 40-50% in both treatment groups. Plasma glucose and glucose production initially increased 2-fold with glucagon replacement, and subsequently declined by 2-3 h to levels comparable to those observed with somatostatin alone. After 6 h plasma glucose and glucose kinetics were no different whether or not glucagon was present. The rise in blood ketones after somatostatin was not exaggerated by glucagon replacement. We conclude that glucagon lack is not a modifying factor in the late hyperglycemic and hyperketonemic response to prolonged infusions of somatostatin.