PubMed Health⌕ Search

Biomedical subjects

Denis Daneman

Publications and source records attributed to Denis Daneman.

At least 19 recordsLinked to original sources

Type 1 diabetes.

Type 1 diabetes accounts for only about 5-10% of all cases of diabetes; however, its incidence continues to increase worldwide and it has serious short-term and long-term implications. The disorder has a strong genetic component, inherited mainly through the HLA complex, but the factors that trigger onset of clinical disease remain largely unknown. Management of type 1 diabetes is best undertaken in the context of a multidisciplinary health team and requires continuing attention to many aspects, including insulin administration, blood glucose monitoring, meal planning, and screening for comorbid conditions and diabetes-related complications. These complications consist of microvascular and macrovascular disease, which account for the major morbidity and mortality associated with type 1 diabetes. Newer treatment approaches have facilitated improved outcomes in terms of both glycaemic control and reduced risks for development of complications. Nonetheless, major challenges remain in the development of approaches to the prevention and management of type 1 diabetes and its complications.

Adolescent↗

Parent and health professional perspectives in the management of adolescents with diabetes: development of assessment instruments for international studies.

OBJECTIVE: Assessment of quality of life (QOL) in adolescents with diabetes requires patient, parent and health professional input. Psychometrically robust instruments to assess parent and professional perspectives are required. RESEARCH DESIGN AND METHODS: Questionnaires concerning adolescent QOL were developed for completion by parents and health professionals. In an international study assessing QOL in 2,101 adolescents with diabetes (median age 14 years, range 10-18; from 17 countries including Europe, Japan and North America), parents and health professionals completed their respective questionnaires between March and August 1998. RESULTS: Feasibility and acceptability of the new questionnaires were indicated by high questionnaire completion rates (adolescents 92%; parents 89%; health professionals 94%). Internal consistency was confirmed (Cronbach's alpha coefficients 0.80 parent; 0.86 health professional). Correlations of Diabetes Quality of Life Questionnaire for Youths (DQOLY) scores with parent and health professional global QOL ratings were generally low (r ranging from 0.12 to 0.36). Parent-rated burden decreased incrementally across adolescence, particularly for girls. Professional-rated burden followed a similar profile but only after age 15 years. Until then, burden was rated as uniformly high. Clinically relevant discrepancies in parent and professional burden scores were noted for one-parent families and families where adolescents had been referred for psychological help. In both cases, health professionals but not one-parent families perceived these as high burden situations. The clinical significance of this relates to the significantly poorer metabolic control recorded for adolescents in both situations. CONCLUSIONS: Parent and health professional questionnaires were found to have adequate internal consistency, and convergent and discriminant validity in relation to key clinical and QOL outcomes. The questionnaires are brief, easy to administer and score. They may also enable comparisons across countries and languages to facilitate development of international health outcome parameters. The inclusion of the parent and health professional perspectives completes a comprehensive assessment of adolescent QOL relevant to diabetes.

Adolescent↗

Pioglitazone as adjunctive therapy in adolescents with type 1 diabetes.

OBJECTIVE: To determine whether the addition of the thiazoladinedione, pioglitazone, to standard therapy improves metabolic control in adolescents with type 1 diabetes (T1D) and clinical evidence of insulin resistance. STUDY DESIGN: Randomized, placebo-controlled 6-month 2-site trial of pioglitazone therapy in 35 adolescents with T1D, high insulin requirements (>0.9 U/kg/d), and suboptimal metabolic control (A1c 7.5%-11%), with the primary outcome of change in A1c. Secondary outcomes include change in insulin dose, body mass index (BMI), lipids, and waist and hip circumference. RESULTS: Metabolic control (A1c) was improved at 6 months in all subjects (P = .02). There was no significant difference between the pioglitazone and placebo treatment groups at 6 months in either change in A1c (-0.4% +/- 0.9% and -0.5% +/- 1.2%, respectively) or insulin dose. BMI SDS increased by 0.3 +/- 0.3 (kg/m(2)) in the pioglitazone group and remained unchanged in the placebo group (P = .01). There was no significant difference in change in any lipid parameters between the pioglitazone and placebo groups at 6 months. CONCLUSIONS: Adjunctive pioglitazone therapy was not effective in improving glycemic control in adolescents with T1D. Pioglitazone was associated with increased BMI.

Adolescent↗

Diagnostic imaging of the thyroid and adrenal glands in childhood.

This article reviews the clinical utility of modern imaging techniques, particularly ultrasound (US), CT, and MRI in children with disorders of the thyroid and adrenal glands. Radionuclide scanning is the modality of choice in making the anatomic diagnosis in neonates with congenital hypothyroidism, while US is most useful in defining nodular thyroid disease. CT and MRI of the thyroid tend to be limited to defining the extent of thyroid carcinoma. Adrenal US is an essential step in the differential diagnosis of ambiguous genitalia or salt-losing crises in the newborn, while CT and MRI are more useful in defining the anatomy of the adrenals in older children with tumors or diffuse hyperplasia of the glands.

Adrenal Gland Diseases↗

Population-based study of incidence and risk factors for cerebral edema in pediatric diabetic ketoacidosis.

OBJECTIVES: To determine incidence, outcomes, and risk factors for pediatric cerebral edema with diabetic ketoacidosis (CEDKA) in Canada. STUDY DESIGN: This was a case-control study nested within a population-based active surveillance study of CEDKA in Canada from July 1999 to June 2001. Cases are patients with DKA <16 years of age with cerebral edema. Two unmatched control subjects per case are patients with DKA without cerebral edema. RESULTS: Thirteen cases of CEDKA were identified over the surveillance period for an incidence rate of 0.51%; 23% died and 15% survived with neurologic sequelae. CEDKA was present at initial presentation of DKA in 19% of cases. CEDKA was associated with lower initial bicarbonate ( P = .001), higher initial urea ( P = .001), and higher glucose at presentation ( P = .014). Although there was a trend to association with higher fluid rates and treatment with bicarbonate, these were not independent predictors. CONCLUSIONS: CEDKA remains a significant problem with a high mortality rate. No association was found between the occurrence of CEDKA and treatment factors. The presence of cerebral edema before treatment of DKA and the association with severity of illness suggest that prevention of DKA is the key to avoiding this devastating complication.

Adolescent↗

Continuous glucose monitoring in adolescents with cystic fibrosis.

The presence of cystic fibrosis (CF)-related diabetes was evaluated in 19 adolescents with CF by continuous glucose monitoring system (CGMS) and oral glucose tolerance testing. CGMS confirmed diabetic glucose excursions in 7/19 subjects deemed diabetic on oral glucose tolerance testing. CGMS is a useful tool for detecting hyperglycemia in CF.

Adolescent↗

Insulin analogues in children and teens with type 1 diabetes: advantages and caveats.

This article reviews the advantages to and caveats of the use of newer insulin formulations (insulin analogues) and regimens in children and teens who have type 1 diabetes, their affect on glycemic control, frequency of hypoglycemic events, daily insulin requirements, and adverse affects such as excessive weight gain, which provides a further major challenge in adolescents. We also address briefly the use of adjunctive agents in the treatment of type 1 diabetes in children and teens.

Adolescent↗

Self-monitoring of blood glucose in children and teens with diabetes.

Improved metabolic control has unequivocally been demonstrated to delay the onset and slow the progression of microvascular complications in adolescents and adults with diabetes mellitus. Growing evidence also supports the association of tighter glucose control and more frequent blood glucose monitoring. Therefore, self-monitoring of blood glucose (SMBG) has become a fundamental part of diabetes care in children. Here, we review recent advances and ongoing trends in glucose monitoring in children with diabetes. Technologies have been developed to improve patient compliance with recommended monitoring, requiring less blood, involving less pain, and providing results more quickly. Alternate-site testing (AST) is also a potential means of improving patient compliance with SMBG by avoiding the sensitive fingertip area. The Continuous Glucose Monitoring System (CGMS) and the GlucoWatch Biographer are two recent tools that can track glucose levels continuously. However, inconsistency in their accuracy and precision remain challenges when using these technologies to guide management.

Adolescent↗

Predictors of glucose control in children and adolescents with type 1 diabetes mellitus.

AIMS: To evaluate the glucose control [(as measured by hemoglobin A1c (HbA1c)], the factors associated with glycemic control, and possible explanations for these associations in a sample of children and adolescents with type 1 diabetes. METHODS: Data were collected on 155 children and adolescents, with type 1 diabetes mellitus, attending a multidisciplinary diabetes clinic in Portland, OR. Patients' hospital charts were reviewed to determine demographic factors, disease-related characteristics, and HbA1c level. RESULTS: Mean percent HbA1c was 9.3. Adolescents between the ages of 14 and 18 yr were in poorer metabolic control (adjusted mean percent HbA1c 0.56 higher than children 2-8 yr). Children who attended the clinic three to four times in the previous year were in better control (adjusted mean percent HbA1c 0.46 lower than those who visited two or fewer times and 1.11 lower than those who attended five or more times). Children with married parents were in better glycemic control than those of single, separated, or divorced parents (adjusted mean percent HbA1c 0.47 lower for children of married parents). This effect appeared to be mediated, in part, by the number of glucose checks performed per day. CONCLUSIONS: This study suggests that adolescents should be targeted for improved metabolic control. Diabetes team members need to be aware of changing family situations and provide extra support during stressful times. Regular clinic attendance is an important component of intensive diabetes management. Strategies must be developed to improve accessibility to the clinic and to identify patients who frequently miss appointments.

Adolescent↗

Early diabetes-related complications in adolescents: risk factors and screening.

Micro- and macrovascular complications account for the major part of the morbidity and mortality associated with diabetes developing in childhood. Although advanced complications are exceptionally rare in the adolescent age group, it is during this phase that the progression of risk may accelerate. A number of potentially important factors have been identified which might contribute to risk of complication development: some provide insights into the genetics of these complications, while others are potentially modifiable, such as metabolic control, hypertension, smoking, obesity and hyperlipidemia. Recently, both consensus and evidence-based guidelines have been developed to guide those involved in the care of adolescents with diabetes in the prevention, screening and management of early diabetes-related complications in this vulnerable population. This article reviews the literature that underpins the available guidelines and stresses the pivotal role of excellent metabolic control in complication prevention.

Adolescent↗

Color visual evoked potentials in children with type 1 diabetes: relationship to metabolic control.

PURPOSE: To examine the association between metabolic control (HbA(1c)) and the chromatic mechanisms of children with type 1 diabetes (T1D), by using the color visual evoked potential (VEP). METHODS: Fifty children with T1D (age range, 6-12.9 years) and 33 age-matched control subjects were tested. VEPs were recorded by placing five electrodes on the scalp according to the International 10/20 System of Electrode Placement. Active electrodes O1, O2, and Oz were placed over the visual cortex. Short-wavelength (S), and long- and medium-wavelength (LM) color stimuli consisted of vertical, photometric isoluminant (1 cyc/deg) gratings presented in a pattern onset (100 ms)-offset (400 ms) mode. Achromatic vertical gratings were presented at 3 cyc/deg. Primary outcome measure was VEP latency. The relationship between S, LM, and achromatic VEP latency, and HbA(1c) was determined by ANCOVA regression. RESULTS: S-, LM-, achromatic VEP latencies were not associated significantly with HbA(1c). Pubertal status, however, was associated significantly (P = 0.0114) and selectively with S-VEP latency. Pubertal children with T1D had delayed (mean delay, 9.5 ms) S-VEP latencies when compared with the prepubertal children with T1D. However, there was no statistically significant difference (P = 0.1573) in the effect of pubertal status on S-VEP latency between the T1D and control groups. CONCLUSIONS: Pubertal status rather than HbA(1c) appears to affect selectively the S-VEP latency of preteen children with T1D. Further study is warranted to determine whether the delay in S-VEP latency in pubertal children with T1D changes over time and whether this change could be a predictive marker for future development of background diabetic retinopathy.

Blood Glucose↗

Growth hormone deficiency in Costello syndrome.

We report on three patients with Costello syndrome and isolated growth hormone (GH) deficiency treated with biosynthetic GH. To our knowledge, these are the only patients with Costello syndrome who have been successfully treated for GH deficiency. We review the pathophysiology of Costello syndrome and highlight the recent recommendations of tumor screening and cardiac surveillance in this population, of particular relevance to those receiving GH therapy.

Abnormalities, Multiple↗

Early onset of severe diabetes mellitus-related microvascular complications.

A 16-year-old girl with type 1 diabetes developed painful peripheral neuropathy within 1 month and proliferative retinopathy within 1 year despite excellent glycemic control. We speculate on potential mechanisms that may have contributed to the rapid development of diabetes mellitus-related complications.

Adolescent↗

Is carotid ultrasound a useful tool in assessing cardiovascular disease in individuals with diabetes?

Coronary heart disease is a major cause of morbidity and mortality in North America. Its prevention is therefore an important clinical goal. Individuals with both Type 1 and Type 2 diabetes mellitus are at increased risk of developing heart disease as compared with those without diabetes. Carotid ultrasound is now a well-validated tool to study the presence and progression of cardiovascular disease. Using ultrasound one can determine elastic properties of the vessel wall (distensibility and compliance) as well as intima-media thickness (IMT). Several large studies have shown that IMT is a useful predictor of future cardiovascular events such as myocardial infarction and stroke, and is well correlated with other traditional risk factors such as blood pressure, lipids, level of glycemic control, and smoking. For this reason, carotid ultrasound may add valuable clinical information above and beyond that provided by traditional risk factors. The use of carotid ultrasound in the pediatric and adolescent population is increasing, and one study has shown decreased distensibility in adolescents with Type 1 diabetes mellitus versus controls. However, IMT measurements in the children and teens with Type 1 diabetes have yielded conflicting results, and larger, longitudinal studies are needed in this area.

Adolescent↗

Cardiac and vascular function in adolescents and young adults with type 1 diabetes.

The objective was to prospectively define cardiac and vascular function in adolescents and young adults with type 1 diabetes over a 3-year period. Thirty-three subjects with type 1 diabetes were studied in 1998, and 28 returned for follow-up in 2001. There were 28 controls without diabetes. All subjects underwent ultrasonography of the carotid artery to determine distensibility, compliance, and intimal-medial thickness, as well as echocardiographic studies, lipid profile, and measurement of hemoglobin A1c (HbA1c) levels and urinary albumin excretion rate. The diabetes group showed no significant change over the 3-year follow-up in lipid profile, HbA1c level, or albumin excretion rate, but a significant increase in body mass index. The diabetes and control groups were similar in age, lipid profile, and albumin excretion rate. Carotid artery distensibility and compliance in the diabetes group increased significantly from baseline to follow-up but did not differ significantly from controls. The intimal-medial thickness of the diabetes group remained unchanged over time but tended to be higher than controls. Echocardiographic studies showed no difference between the diabetes and control groups, but there was a small change in left ventricular posterior diastolic wall diameter in the subjects with diabetes over the 3-year period. There was an overall improvement in carotid function and no change in cardiac measures in subjects with diabetes over the 3 years, such that cardiac and vascular function were similar to those of controls. The reason for the improvement is uncertain, but may relate to the improvement of insulin sensitivity at the end of the pubertal growth period, rather than to changes in metabolic control or lipid profiles.

Adolescent↗

Growth and sexual maturation during long-term treatment with risperidone.

OBJECTIVE: This study assessed the impact of risperidone on growth and sexual maturation. METHOD: The pooled database of five studies included 700 children ages 5-15 years with disruptive behavior disorders. All evaluable patients had received risperidone for 11 or 12 months. Those evaluable for growth also had baseline and 11- or 12-month height measurements (N=350); girls >/=9 years and boys >/=10 years who were evaluable for sexual maturation also had baseline and 11- or 12-month Tanner staging (N=222). RESULTS: Risperidone-treated children had a mean increase in height 1.2 cm greater than the reference population, and they experienced no delay in progression through Tanner staging. Transient increases in prolactin did not correlate with growth or sexual maturation. CONCLUSIONS: In this retrospective analysis, there was no evidence of statistically or clinically significant growth failure or delay in pubertal onset or progression in children treated for up to 1 year with risperidone.

Adolescent↗