Contemporary rates of severe hypoglycaemia in youth with type 1 diabetes: variability by insulin regimen

AIMS

To determine incidence rates of severe hypoglycaemia and compare incidence rates by insulin regimen in a diverse sample of youth with Type 1 diabetes from two sites.

METHODS

In this observational study, 255 youth (51% female) aged 9-15 years receiving varied insulin regimens provided data prospectively for a median of 1.2 years. Reported episodes of severe hypoglycaemia, defined as episodes requiring help from another person for oral treatment or episodes resulting in seizure/coma, and current insulin regimens were collected systematically. Incidence rates were calculated and compared according to insulin regimen in bivariate and multivariate analyses.

RESULTS

At first encounter, participants had a median age of 12.2 years (range 9.0-15.0), median diabetes duration of 4.4 years (range 1.0-13.0) and mean HbA(1c) of 67 ± 12 mmol/mol (8.3 ± 1.1%). The incidence rate was 37.6/100 patient-years for all severe hypoglycaemia and 9.6/100 patient-years for seizure/coma. The incidence rate for severe hypoglycaemia was 31.8/100 patient-years on continuous subcutaneous insulin infusion (pump therapy), 34.4/100 patient-years on basal-bolus injections and 46.1/100 patient-years on NPH (NPH vs. pump therapy: P = 0.04). The incidence rate for seizure/coma was 4.5/100 patient-years on pump therapy, 11.1/100 patient-years on basal-bolus injections and 14.4/100 patients-years on NPH (NPH vs. pump therapy: P = 0.004). In the multivariate analysis, the rate of seizure/coma was significantly higher for those on NPH vs. pump therapy (rate ratio 2.9, P = 0.03).

CONCLUSIONS

Rates of severe hypoglycaemia in youth with Type 1 diabetes remain high. Pump therapy was associated with lower rates of all severe hypoglycaemia and seizure/coma in comparison with NPH.

Affordability of a nutritious diet for income assistance recipients in Nova Scotia (2002-2010)

OBJECTIVE

This study assessed the affordability of a basic nutritious diet for selected household types relying on income assistance (IA) by comparing potential incomes to the costs of the National Nutritious Food Basket (NNFB) and other essential expenditures in Nova Scotia from 2002 to 2010, and examined the adequacy of IA allowances during this time period.

METHOD

The cost of the NNFB was surveyed across a random sample of grocery stores in NS during five time periods: 2002, 2004/05, 2007, 2008 and 2010, and was factored into affordability scenarios for three household types relying on IA: a family of four, a lone mother with three children, and a lone male. Essential monthly expenses were deducted from total net income to determine if adequate funds remained for the NNFB.

RESULTS

For each time period examined, the findings demonstrated that all household types faced a significant monthly deficit if they purchased a basic nutritious diet. In each household scenario, the potential monthly deficits increased from 2002 to 2010, ranging from $112 in 2002 for a lone mother with three children to $523 in 2010 for a lone male.

CONCLUSION

Despite increases in allowances, these findings suggest that the risk of food insecurity has increased for IA-dependent households in NS. To address this public health challenge, public health practitioners must advocate for integrated, progressive and sustainable social welfare policies that ensure that individuals and families relying on IA have adequate income and other supports to meet their basic needs, including access to a healthy diet.

Habitat associations of species show consistent but weak responses to climate

Different vegetation types can generate variation in microclimates at local scales, potentially buffering species from adverse climates. To determine if species could respond to such microclimates under climatic warming, we evaluated whether ectothermic species (butterflies) can exploit favourable microclimates and alter their use of different habitats in response to year-to-year variation in climate. In both relatively cold (Britain) and warm (Catalonia) regions of their geographical ranges, most species shifted into cooler, closed habitats (e.g. woodland) in hot years, and into warmer, open habitats (e.g. grassland) in cooler years. Additionally, three-quarters of species occurred in closed habitats more frequently in the warm region than in the cool region. Thus, species shift their local distributions and alter their habitat associations to exploit favourable microclimates, although the magnitude of the shift (approx. 1.3% of individuals from open to shade, per degree Celsius) is unlikely to buffer species from impacts of regional climate warming.

Re-examining a measure of diabetes-related burden in parents of young people with Type 1 diabetes: the Problem Areas in Diabetes Survey - Parent Revised version (PAID-PR)

AIMS

In a pediatric patients, the burden of diabetes lies within the family. In the current era of intensive insulin therapy, perceived parental burden may affect the family's efforts at effective diabetes management. The aims of this study were to re-examine and revise a measure of perceived parental burden associated with caring for a child with diabetes in the current era.

METHODS

A geographically diverse population of young people (N = 376) with Type 1 diabetes and their parents included participants in the Juvenile Diabetes Research Foundation continuous glucose monitoring study and patients from the Joslin Diabetes Center. Participants provided data on demographics, diabetes management, diabetes-specific family conflict, and quality of life at baseline and after 6 months of follow-up.

RESULTS

Young people were 12.9 ± 2.7 years old with diabetes duration of 6.3 ± 3.5 years. Mean HbA(1C) was 8.0 ± 1.2%(64 mmol/mol), 58% received insulin pump therapy, and young people monitored blood glucose 5.2 ± 2.3 times/day. Factor analysis yielded two factors, 'Immediate Burden' and 'Theoretical Burden'. The Problem Areas in Diabetes Survey - Parent Revised version (PAID-PR) demonstrated excellent internal consistency (Cronbach's α = 0.87; factor 1 α = 0.78; factor 2 α = 0.83). Greater parental burden was associated with more frequent blood glucose monitoring, higher HbA(1C) levels, greater diabetes-specific family conflict, and lower quality of life. Test-retest analysis was acceptable (r = 0.62).

CONCLUSIONS

The PAID-PR demonstrated excellent internal consistency, good test-retest reliability, and associations with diabetes-specific family conflict and quality of life. This brief measure may have both clinical and research utility in the management of young people with Type 1 diabetes.

Integrating an Automated Diabetes Management System into the family management of children with type 1 diabetes: results from a 12-month randomized controlled technology trial

OBJECTIVE

The study objective was to evaluate how the use of a pervasive blood glucose monitoring (BGM) technology relates to glycemic control, report of self-care behavior, and emotional response to BGM of children with type 1 diabetes and their parents.

RESEARCH DESIGN AND METHODS

Forty-eight children aged less than 12 years (mean 8.8 years) with type 1 diabetes were randomly assigned to one of two study groups, a control group (conventional care without technology) or an experimental group (conventional care with technology), and followed for 12 months. Families in the experimental group were given the Automated Diabetes Management System (ADMS), which automatically collects blood glucose (BG) values and sends to parent(s) a 21-day BG trending report via e-mail each night. Measures of glycemic control (HbA(1c)) were collected at baseline and at quarterly diabetes clinic visits; BGM effect and diabetes self-care behavior measures were obtained at the baseline, 6-month, and 12-month visits.

RESULTS

Children in the experimental group had significantly (P = 0.01) lower HbA(1c) at 12 months (7.44 ± 0.94, -0.35 from baseline) than controls (8.31 ± 1.24, +0.15 from baseline). Improvement in HbA(1c) was more profound in families using the ADMS more frequently. In addition, in these families, parents showed a significant improvement in BGM effect (P = 0.03) and children became more meticulous in diabetes self-care (P = 0.04). Children in both experimental and control groups experienced no change in their emotional response to BGM.

CONCLUSIONS

Using the ADMS 1-3 times/week may help children with type 1 diabetes improve glycemic control and gain diabetes self-management skills, as well as improve the BGM effect of parents.

Behavioral research in pediatric diabetes: putting the evidence to work for advocacy and education

Dr Henri Lestradet was a founding member of the International Study Group for Diabetes (in childhood and adolescence) (ISGD), and his influence on the scope and vision of this organization was profound. A brief biography of Dr Lestradet and a summary of how his original ISGD evolved into the current International Society for Pediatric and Adolescent Diabetes (ISPAD) will be presented first. Second, consistent with Dr Lestradet's vision for children with diabetes worldwide, I will suggest five areas of behavioral research in diabetes in which there is strong evidence that can be used to create educational and advocacy initiatives for children with diabetes. Finally, I will recommend several priorities for behavioral research in the next decade which will help to strengthen Prof. Lestradet's legacy of support for children with diabetes and their families.

Adult minimal oral sedation in the general practice setting

Patients who are phobic, elderly, physically disabled, or mentally impaired pose unique challenges in the dental operating environment. Reducing stress during the dental appointment allows for improved cooperation, safety, and clinical efficiency. There is an increased need for dentists who are able to confidently and competently render care to these patients. Adult oral conscious sedation at the minimal level is a valuable way to more effectively manage the specific dental needs of this growing population.

Comparison of longitudinal point-of-care and high-performance liquid chromatography HbA1c measurements in a multi-centre trial

AIMS

Point-of-care HbA(1c) is routine in clinical practice. Comparison of point-of-care HbA(1c) against laboratory measurements across sites and over time is warranted.

METHODS

One hundred and twenty-one young persons with Type 1 diabetes from four centres provided 450 paired samples collected over 10 months for point-of-care HbA(1c) and central laboratory-based high-performance liquid chromatography (HPLC) HbA(1c) determinations. Change in HbA(1c) over time was assessed by difference from initial to final HbA(1c) and by growth modelling with annualized slope calculation. Change in HbA(1c) was categorized as improved (decrease of ≥ 0.5% or negative slope), no change (± 0.4% of initial HbA(1c) or slope = 0) or worsened (increase of ≥ 0.5% or positive slope).

RESULTS

The 450 paired samples (median of four pairs/patient) were highly correlated (r = 0.97, P < 0.0001), as were time-specific and site-specific pairs (r = 0.94 to 0.98, P < 0.0001). Initial-to-final point-of-care HbA(1c) and HPLC HbA(1c) changes were 0.3 ± 1.1% (range -2.7 to 4.1) and 0.4 ± 1.2% (-3.9 to 4.5), respectively, with 21% of patients (n = 26) discordant for change categories. ΔHbA(1c) by point-of-care HbA(1c) vs. HPLC HbA(1c) differed across the HbA(1c) range and by ≥ 0.5% absolute difference in ΔHbA(1c) in 14 (54%) of the 26 patients discordant for HbA(1c) change categories. Mean annual HbA(1c) slope was 0.4 ± 1.5% (-5.4 to 4.8) for point-of-care HbA(1c) and 0.4 ± 1.6% (-6.9 to 5.2) for HPLC HbA(1c), with 18% (n = 22 pairs) discordant for change categories.

CONCLUSIONS

Assessment of absolute HbA(1c) change may not be different for point-of-care HbA(1c) compared with HPLC HbA(1c); however, misclassification of patients by discrete cut-off values may occur with point-of-care HbA(1c) compared with HPLC HbA(1c) determinations.

What can we learn from patient-reported outcomes of insulin pen devices?

Although a variety of effective treatment options are available for patients with type 1 or type 2 diabetes, many patients in the United States have difficulty reaching their glycemic goals. Patient adherence to insulin therapy, which often involves self-administered subcutaneous injections of insulin using either a vial and syringe or an insulin pen device, is often poor. Various factors associated with the type of injection device have been shown to influence the rate of patient adherence to insulin therapy. This article reviews patient-reported outcome (PRO) evidence from pediatric and adult studies that compared insulin pen devices with vial and syringe use. In a majority of these cases, patients preferred the pen devices over vial and syringe, stating advantages such as ease of use, convenience, greater confidence in their ability to properly administer the drug, and a greater perceived social acceptance. The pens were considered less painful than syringes and were associated with less needle fear. In addition, PRO evidence has directed pen technology design, leading to development of more advanced insulin pen devices. By appreciating the correlation between adherence to insulin regimens and a patient's device preference, clinicians can make improved treatment recommendations to facilitate achievement and maintenance of glycemic targets.

Depressive symptoms and quality of life in adolescents with type 2 diabetes: baseline data from the TODAY study

OBJECTIVE

The study objective was to examine the prevalence of depressive symptoms and relationships to quality of life and demographics in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study's large, ethnically diverse youth with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 704 youth with type 2 diabetes <2 years' duration, aged 10-17 years, and BMI ≥85th percentile completed depressive symptoms and quality of life measures.

RESULTS

Some 14.8% reported clinically significant depressive symptoms, and older girls had significantly higher rates than older boys.

CONCLUSIONS

Rates of significant depressive symptoms were similar to those of healthy adolescents and lower than those of teens with type 1 diabetes. Elevated depressive symptoms, particularly in older girls, suggest clinicians assess vulnerability.

Spatial covariation between freshwater and terrestrial ecosystem services

To inform the design and implementation of land-use policies that consider the variety of goods and services people derive from ecosystems, it is essential to understand spatial patterns of individual services, how multiple services relate to each other, and how these relationships vary across spatial scales and localities. Despite the importance of freshwater as a determinant of regional economic and human demographic patterns, there are surprisingly few studies that map the provision of a range of services associated with the quality of the aquatic environment. Here we examine relationships between indicators of riverine water and associated habitat quality, freshwater biodiversity, three terrestrial ecosystem services, and terrestrial biodiversity across England and Wales. The results indicate strong associations between our indicators of freshwater services. However, a comparison of these indicators of freshwater services with other ecosystem services (carbon storage, agricultural production, recreation) and biodiversity of species of conservation concern in the surrounding terrestrial landscape shows no clear relationships. While there are potential policy "win-wins" for the protection of multiple services shown by associations between indicators of freshwater services and carbon storage in upland areas of Britain, the other ecosystem services showed either negative or no relationships with the indicators of freshwater services. We also consider the influence that spatial scale has on these relationships using River Basin Districts. Our results indicate that relationships between indicators of services can change dramatically depending on the societal pressures and other regional conditions. Thus, the delivery of multiple ecosystem services requires the development of regional strategies, or of national strategies that take account of regional variation.

Validation of an abbreviated adherence measure for young people with Type 1 diabetes

AIMS

Adherence to diabetes-related tasks is an important construct. The Diabetes Self-Management Profile is a validated, semi-structured interview assessing adherence in paediatric patients with Type 1 diabetes. We created and validated a brief questionnaire version of the Diabetes Self-Management Profile called the Diabetes Self-Management Questionnaire.

METHODS

Young people with Type 1 diabetes, ages 9-15 years (n = 338) and their parents provided data from chart review, interview and questionnaires.

RESULTS

Diabetes Self-Management Questionnaire scores correlated significantly with Diabetes Self-Management Profile scores, HbA(1c) , blood glucose monitoring frequency and other measures associated with adherence and/or glycaemic control (P ≤ 0.01 for all). Young people and parent scores were correlated (r = 0.55, P < 0.0001). The Diabetes Self-Management Questionnaire demonstrated modest internal consistency (Cronbach's α = 0.59), adequate for a brief measure of multidimensional adherence. In addition, factor analysis confirmed one factor.

CONCLUSIONS

This brief adherence questionnaire demonstrated construct validity in young people 9-15 years old and their parents and may have utility in clinical and research settings.

Balancing alternative land uses in conservation prioritization

Pressure on ecosystems to provide various different and often conflicting services is immense and likely to increase. The impacts and success of conservation prioritization will be enhanced if the needs of competing land uses are recognized at the planning stage. We develop such methods and illustrate them with data about competing land uses in Great Britain, with the aim of developing a conservation priority ranking that balances between needs of biodiversity conservation, carbon storage, agricultural value, and urban development potential. While both carbon stocks and biodiversity are desirable features from the point of view of conservation, they compete with the needs of agriculture and urban development. In Britain the greatest conflicts exist between biodiversity and urban areas, while the largest carbon stocks occur mostly in Scotland in areas with low agricultural or urban pressure. In our application, we were able successfully to balance the spatial allocation of alternative land uses so that conflicts between them were much smaller than had they been developed separately. The proposed methods and software, Zonation, are applicable to structurally similar prioritization problems globally.

Thiopentone elimination in newborn infants: exploring Michaelis-Menten kinetics

BACKGROUND

Thiopentone elimination has been described using Michaelis-Menten pharmacokinetics in adults after prolonged infusion or overdose, but there are few reports of elimination in neonates.

METHODS

Time-concentration profiles for neonates (n=37) given single-dose thiopentone were examined using both first-order (constant clearance) and mixed-order (Michaelis-Menten) elimination processes using nonlinear mixed effects models. These profiles included a 33-week post-menstrual age (PMA) neonate given an overdose. A two-compartment mamillary model was used to fit data. Parameter estimates were standardized to a 70 kg person using allometric models.

RESULTS

There were 197 observations available for analysis from neonates with a mean post-menstrual age of 35 (SD 4.5) weeks and a mean weight of 2.5 (SD 0.9) kg. They were given a mean thiopentone dose of 3 (SD 0.4) mg/kg as a rapid bolus. Clearance at 26 weeks PMA was 0.015 l/min/70 kg and increased to 0.119 l/min/70 kg by 42 weeks PMA. The maximum rate of elimination (V(max)) at 26 weeks PMA was 0.22 mg/min/70 kg and increased to 4.13 mg/min/70 kg by 42 weeks PMA. These parameter estimates are approximately 40% adult values at term gestation. The Michaelis constant (K(m)) was 28.3 [between subject variability (BSV) 46.4%, 95% confidence interval (CI) 4.49-99.2] mg/l; intercompartment clearance was 0.44 (BSV 97.5%, 95% CI 0.27-0.63) l/min/70 kg; central volume of distribution was 46.4 (BSV 29.2%, 95% CI 41.7-59.8) l/70 kg; peripheral volume of distribution was 95.7 (BSV 70.3%, 95% CI 61.3-128) l/70 kg.

CONCLUSIONS

Both first-order and mixed-order processes satisfactorily described elimination. First-order elimination adequately described the time-concentration profile in the premature neonate given an overdose. Clearance is immature in the pre-term neonate although there is rapid maturation around 40 weeks PMA, irrespective of post-natal age.

Improvement and emergence of insulin restriction in women with type 1 diabetes

OBJECTIVE

To determine the distinguishing characteristics of women who report stopping insulin restriction at 11 years of follow-up from those continuing to endorse insulin restriction as well as those characteristics differing in patients who continue to use insulin appropriately from new insulin restrictors.

RESEARCH DESIGN AND METHODS

This is an 11-year follow-up study of 207 women with type 1 diabetes. Insulin restriction, diabetes self-care behaviors, diabetes-specific distress, and psychiatric and eating disorder symptoms were assessed using self-report surveys.

RESULTS

Of the original sample, 57% participated in the follow-up study. Mean age was 44 ± 12 years, diabetes duration was 28 ± 11 years, and A1C was 7.9 ± 1.3%. At follow-up, 20 of 60 baseline insulin restrictors had stopped restriction. Women who stopped reported improved diabetes self-care and distress, fewer problems with diabetes self-management, and lower levels of psychologic distress and eating disorder symptoms. Logistic regression indicated that lower levels of fear of weight gain with improved blood glucose and fewer problems with diabetes self-management predicted stopping restriction. At follow-up, 34 women (23%) reported new restriction, and a larger proportion of new insulin restrictors, relative to nonrestrictors, endorsed fear of weight gain with improved blood glucose.

CONCLUSIONS

Findings indicate that fear of weight gain associated with improved blood glucose and problems with diabetes self-care are core issues related to both the emergence and resolution of insulin restriction. Greater attention to these concerns may help treatment teams to better meet the unique treatment needs of women struggling with insulin restriction.

Feasibility, acceptability, and predictive validity of a psychosocial screening program for children and youth newly diagnosed with type 1 diabetes

OBJECTIVE

Psychosocial screening has been recommended for pediatric patients with newly diagnosed type 1 diabetes and their families. Our objective was to assess a psychosocial screening protocol in its feasibility, acceptability to families, and ability to predict early emerging complications, nonadherent family behavior, and use of preventive psychology services.

RESEARCH DESIGN AND METHODS

A total of 125 patients and their caregivers were asked to participate in a standardized screening interview after admission at a large urban children's hospital with a new diagnosis of type 1 diabetes. Medical records were reviewed for subsequent diabetes-related emergency department (ED) admissions, missed diabetes clinic appointments, and psychology follow-up within 9 months of diagnosis.

RESULTS

Of 125 families, 121 (96.8%) agreed to participate in the screening, and a subsample of 30 surveyed caregivers indicated high levels of satisfaction. Risk factors at diagnosis predicted subsequent ED admissions with a sensitivity of 100% and a specificity of 98.6%. Children from single-parent households with a history of behavior problems were nearly six times more likely to be seen in the ED after diagnosis. Missed appointments were likeliest among African Americans, 65% of whom missed at least one diabetes-related appointment. Psychology services for preventive intervention were underutilized, despite the high acceptability of the psychosocial screening.

CONCLUSIONS

Psychosocial screening of newly diagnosed patients with type 1 diabetes is feasible, acceptable to families, and able to identify families at risk for early emerging complications and nonadherence. Challenges remain with regards to reimbursement and fostering follow-up for preventive care.

Influence of obesity on propofol pharmacokinetics: derivation of a pharmacokinetic model

BACKGROUND

The objective of this study was to develop a pharmacokinetic (PK) model to characterize the influence of obesity on propofol PK parameters.

METHODS

Nineteen obese ASA II patients undergoing bariatric surgery were studied. Patients received propofol 2 mg kg(-1) bolus dose followed by a 5-20-40-120 min, 10-8-6-5 mg kg(-1) h(-1) infusion. Arterial blood samples were withdrawn at 1, 3, 5 min after induction, every 10-20 min during propofol infusion, and every 10-30 min for 2 h after stopping the propofol infusion. Arterial samples were processed by high-performance liquid chromatography. Time-concentration data profiles from this study were pooled with data from two other propofol PK studies available at http://www.opentci.org. Population PK modelling was performed using non-linear mixed effects model.

RESULTS

The study involved 19 obese adults who contributed 163 observations. The pooled analysis involved 51 patients (weight 93 sd 24 kg, range 44-160 kg; age 46 sd 16 yr, range 25-81 yr; BMI 33 sd 9 kg m(-2), range 16-52 kg m(-2)). A three-compartment model was used to investigate propofol PK. An allometric size model using total body weight (TBW) was superior to all other models investigated (linear TBW, free fat mass, lean body weight, normal fat mass) for all clearance parameters. Variability in V2 and Q2 was reduced by a function showing a decrease in both parameters with age.

CONCLUSIONS

We have derived a population PK model using obese and non-obese data to characterize propofol PK over a wide range of body weights. An allometric model using TBW as the size descriptor of volumes and clearances was superior to other size descriptors to characterize propofol PK in obese patients.

Blood glucose monitoring and glycemic control in adolescence: contribution of diabetes-specific responsibility and family conflict

PURPOSE

To examine age and time trends in responsibility for diabetes management tasks and diabetes-specific family conflict and their relationship to blood glucose monitoring (BGM) frequency and blood glucose control (HbA1c).

METHODS

A sample of 147 adolescents (mean = 15.5 +/- 1.4 years) with type 1 diabetes and their caregivers completed measures of diabetes-specific responsibility and family conflict at baseline and 6 months. BGM frequency and HbA1c were measured during outpatient clinic appointments.

RESULTS

Responsibility for diabetes management tasks shifted from caregivers to adolescents with increasing age by adolescent and caregiver report. Diabetes-specific conflict was stable. Similar trends in responsibility and conflict were seen over the 6-month follow-up period. Less frequent BGM and higher HbA1c were also observed with increasing adolescent age. Multivariate analyses demonstrated adolescents taking greater responsibility for management tasks and experiencing greater family conflict at baseline reported lower BGM at 6 months. Family, demographic, psychosocial, and disease-specific variables accounted for 26% of the variance in BGM frequency by both adolescent and caregiver report. Adolescents reporting greater diabetes-specific family conflict at baseline experienced higher HbA1c values at 6 months. Variables accounted for 23% and 28% of the variance in HBA1c by adolescent and caregiver report respectively.

CONCLUSIONS

Diabetes-specific responsibility and conflict have important implications for improving disease outcomes. Interventions targeting responsibility and conflict (i.e., reducing conflict while keeping caregivers involved in diabetes management) may help prevent the deterioration in BGM and HbA1c frequently seen during adolescence.

Responsibility sharing between adolescents with type 1 diabetes and their caregivers: importance of adolescent perceptions on diabetes management and control

OBJECTIVE

To analyze associations between factor scores for caregiver responsibility for direct and indirect diabetes management tasks with glycemic control and blood glucose monitoring (BGM) frequency.

METHODS

Two hundred and sixty one adolescents with type 1 diabetes and their caregivers completed the Diabetes Family Responsibility Questionnaire (DFRQ). Data on diabetes management (e.g., BGM frequency) and glycemic control (e.g., A1c values) were obtained.

RESULTS

Confirmatory factor analysis of the DFRQ revealed two factors-direct and indirect management tasks. Multivariate analyses demonstrated that adolescent perception of greater responsibility sharing with caregivers on direct management tasks was significantly associated with higher BGM frequency.

CONCLUSIONS

Adolescents who perceive greater caregiver responsibility, particularly around direct management tasks, engage in better diabetes management. Implications of these findings include designing interventions that encourage and sustain caregiver responsibility through adolescence and make explicit the contribution of caregivers.

Early risk factors for nonadherence in pediatric type 1 diabetes: a review of the recent literature

Nonadherence to different aspects of the diabetes regimen is common. Problems early in the course of illness predict later difficulties with nonadherence; conversely, good management early on protects against later complications. Screening for early risk factors at the time of diabetes diagnosis is therefore critical for promoting the health of children with type 1 diabetes. The purpose of this paper is to review and synthesize the recent empirical literature on early risk factors for nonadherence in type 1 diabetes, with a focus on three specific adherence behaviors: insulin administration, blood glucose monitoring, and clinic attendance. Risk factors are considered within several broad categories: sociodemographic barriers that limit access to care; child and parent factors that affect adherence both directly and indirectly via their impact on the development of family teamwork; and family interactions with their health-care providers. We integrate the different findings into a "simple model" that can be used to develop efficient screening protocols that can in turn guide efforts at preventive intervention.

Brief screening tool for disordered eating in diabetes: internal consistency and external validity in a contemporary sample of pediatric patients with type 1 diabetes

OBJECTIVE To update and validate a diabetes-specific screening tool for disordered eating (the Diabetes Eating Problem Survey [DEPS]) in contemporary youth with type 1 diabetes. RESEARCH DESIGN AND METHODS A total of 112 youth with type 1 diabetes, ages 13-19 years, completed the DEPS. Higher scores on the DEPS indicate more disordered eating behaviors. Youth and their parents also completed additional surveys to examine diabetes-specific family conflict, negative affect related to blood glucose monitoring, youth quality of life, and diabetes burden. Clinicians provided data on height, weight, A1C, and insulin dosing. The DEPS was revised into a shorter, updated measure and validated. RESULTS The revised 16-item DEPS (DEPS-R) displayed excellent internal consistency (Cronbach's alpha = 0.86). Construct validity was demonstrated by positive correlations with zBMI (P = 0.01), A1C (P = 0.001), diabetes-specific family conflict (P < 0.005), youth negative affect around blood glucose monitoring (P = 0.001), parental diabetes-specific burden (P = 0.0005), and negative correlations with frequency of blood glucose monitoring (P = 0.03) and quality of life (P < or = 0.002). External validity was confirmed against clinician report of insulin restriction. CONCLUSIONS The DEPS-R is a 16-item diabetes-specific self-report measure of disordered eating that can be completed in <10 min. It demonstrated excellent internal consistency, construct validity, and external validity in this contemporary sample of youth with type 1 diabetes. Future studies should focus on using the DEPS-R to identify high-risk populations for prevention of and early intervention for disordered eating behaviors.

Combined acetaminophen and ibuprofen for pain relief after oral surgery in adults: a randomized controlled trial

Background

Acetaminophen is often used with a non-steriodal anti-inflammatory drug for acute pain. Hitherto, these drugs have had to be given separately, typically at different time intervals. Maxigesic^® tablets combine acetaminophen and ibuprofen in clinically appropriate doses to simplify administration and dosage regimen. We compared this combination with each of the constituent drugs for the relief of pain after extraction of third molar teeth.

Methods

Adults (more than 16 yr) having one or more wisdom teeth removed under general or local anaesthesia were instructed to take two tablets before operation, then two tablets every 6 h for up to 48 h of: (i) a combination of acetaminophen 500 mg and ibuprofen 150 mg per tablet (Maxigesic^®); (ii) acetaminophen 500 mg per tablet alone; or (iii) ibuprofen 150 mg per tablet alone. The primary outcome measure was the area under the curve (AUC) of the 100 mm visual analogue scale pain measurements taken for up to 48 h after surgery, divided by time, at rest and on activity. Pharmacokinetic data were collected in a subset of patients.

Results

The mean (sem) time-corrected AUC on rest and activity, respectively, were: combination group 22.3 (3.2) and 28.4 (3.4); acetaminophen group 33.0 (3.1) and 40.4 (3.3); and ibuprofen group 34.8 (3.2) and 40.2 (3.4); P<0.01 for each of the four comparisons of combination vs constituent drug. There was no pharmacokinetic interaction between acetaminophen and ibuprofen administered together.

Conclusions

Maxigesic^® tablets provide superior pain relief after oral surgery to acetaminophen or ibuprofen alone.

Ecosystem service benefits of contrasting conservation strategies in a human-dominated region

The hope among policy-makers and scientists alike is that conservation strategies designed to protect biodiversity also provide direct benefits to people by protecting other vital ecosystem services. The few studies that have examined the delivery of ecosystem services by existing conservation efforts have concentrated on large, 'wilderness'-style biodiversity reserves. However, such reserves are not realistic options for densely populated regions. Here, we provide the first analyses that compare representation of biodiversity and three other ecosystem services across several contrasting conservation strategies in a human-dominated landscape (England). We show that small protected areas and protected landscapes (restrictive zoning) deliver high carbon storage and biodiversity, while existing incentive payment (agri-environment) schemes target areas that offer little advantage over other parts of England in terms of biodiversity, carbon storage and agricultural production. A fourth ecosystem service-recreation-is under-represented by all three strategies. Our findings are encouraging as they illustrate that restrictive zoning can play a major role in protecting natural capital assets in densely populated regions. However, trade-offs exist even among the four ecosystem services we considered, suggesting that a portfolio of conservation and sustainability investments will be needed to deliver both biodiversity and the other ecosystem services demanded by society.

Dyadic measures of the parent-child relationship during the transition to adolescence and glycemic control in children with type 1 diabetes

To identify aspects of family behavior associated with glycemic control in youth with type 1 diabetes mellitus during the transition to adolescence, the authors studied 121 9- to 14-year-olds (M = 12.1 yrs) and their parents, who completed the Diabetes Family Conflict Scale (DFCS) and the Diabetes Family Responsibility Questionnaire (DFRQ). From the DFRQ, the authors derived 2 dyadic variables, frequency of agreement (exact parent and child concurrence about who was responsible for a task) and frequency of discordance (opposite parent and child reports about responsibility). The authors divided the cohort into Younger (n = 57, M = 10.6 yrs) and Older (n = 64, M = 13.5 yrs) groups. Family conflict was significantly related to glycemic control in the entire cohort and in both the Younger and Older groups. However, only in the Younger group was Agreement related to glycemic control, with higher Agreement associated with better glycemic control. Findings suggest that Agreement about sharing of diabetes responsibilities may be an important target for family-based interventions aiming to optimize glycemic control in preteen youth.

A multisite trial of a clinic-integrated intervention for promoting family management of pediatric type 1 diabetes: feasibility and design

The feasibility of a family-based clinic-integrated behavioral intervention to improve family management of type 1 diabetes was evaluated. In each of four clinical sites, 30-32 families (a total of 122) were randomized to intervention or usual care comparison groups. The WE*CAN intervention, based on family problem-solving methods, was delivered during three routine clinic visits by trained 'Health Advisors'. Of eligible families across the four sites, 83% agreed to participate, of whom 96% completed the baseline, mid-term, and postintervention assessments. Families participated in an average of 2.85 intervention sessions over an 8-month period. The intervention was integrated into the clinic setting without impairing clinic flow and was implemented with fidelity and consistency across sites by trained non-professionals. The findings provide evidence of the feasibility of conducting a multisite trial to evaluate the effects of a clinic-integrated problem-solving intervention to improve family management. Many lessons were learned that provide guidance for recruitment, measurement, and intervention for the larger clinical trial.

Psychosocial issues in youth with type 2 diabetes mellitus

Little published research exists on psychosocial issues in adolescents with type 2 diabetes mellitus (T2DM), because until two decades ago, diabetes diagnosed in children and adolescents was almost exclusively type 1 diabetes mellitus or insulin-dependent diabetes. In the past two decades, rates of T2DM have increased, especially in adolescents from families of minority racial and ethnic groups. Youth with T2DM are most often obese, have a parent or other first-degree relative with T2DM, and are of low socioeconomic status. To understand the complex set of interrelated psychological and social influences that affect the well-being of youth with T2DM, levels of influence from determinants of genetics, family, and community/societal and minority ethnic groups must be included.

Dynamics of range margins for metapopulations under climate change

We link spatially explicit climate change predictions to a dynamic metapopulation model. Predictions of species' responses to climate change, incorporating metapopulation dynamics and elements of dispersal, allow us to explore the range margin dynamics for two lagomorphs of conservation concern. Although the lagomorphs have very different distribution patterns, shifts at the edge of the range were more pronounced than shifts in the overall metapopulation. For Romerolagus diazi (volcano rabbit), the lower elevation range limit shifted upslope by approximately 700 m. This reduced the area occupied by the metapopulation, as the mountain peak currently lacks suitable vegetation. For Lepus timidus (European mountain hare), we modelled the British metapopulation. Increasing the dispersive estimate caused the metapopulation to shift faster on the northern range margin (leading edge). By contrast, it caused the metapopulation to respond to climate change slower, rather than faster, on the southern range margin (trailing edge). The differential responses of the leading and trailing range margins and the relative sensitivity of range limits to climate change compared with that of the metapopulation centroid have important implications for where conservation monitoring should be targeted. Our study demonstrates the importance and possibility of moving from simple bioclimatic envelope models to second-generation models that incorporate both dynamic climate change and metapopulation dynamics.

Collaborative involvement of primary and secondary caregivers: associations with youths' diabetes outcomes

OBJECTIVE

Collaboration between youths with type 1 diabetes (T1D) and their adult caregivers may be central to effective management of T1D. This article includes analysis of cross-sectional associations between T1D outcomes (adherence, glycemic control, quality of life, family conflict, depression, and self-efficacy) and scores on the Collaborative Parent Involvement (CPI) Scale obtained from 309 youths with T1D about their primary and secondary caregivers.

METHODS

MANCOVA, controlling for age, evaluated associations of diabetes outcomes with youths' CPI scores for each caregiver.

RESULTS

Diabetes outcomes were poor when both caregivers obtained CPI scores below the median. Diabetes outcomes were more strongly associated with CPI scores of primary, rather than secondary, caregivers. CPI scores at or above the median among primary caregivers were associated with more favorable status on multiple youth outcomes. When both caregivers obtained CPI scores at or above the median, children had significantly lower HbA1C and parents retained more responsibility for diabetes care.

CONCLUSIONS

Higher collaborative involvement, particularly among primary caregivers, was associated with favorable status along a variety of diabetes outcomes. Longitudinal studies could confirm if youth-parent collaboration is a justifiable intervention target.

The coincidence of climatic and species rarity: high risk to small-range species from climate change

Why do areas with high numbers of small-range species occur where they do? We found that, for butterfly and plant species in Europe, and for bird species in the Western Hemisphere, such areas coincide with regions that have rare climates, and are higher and colder areas than surrounding regions. Species with small range sizes also tend to occur in climatically diverse regions, where species are likely to have been buffered from extinction in the past. We suggest that the centres of high small-range species richness we examined predominantly represent interglacial relict areas where cold-adapted species have been able to survive unusually warm periods in the last ca 10000 years. We show that the rare climates that occur in current centres of species rarity will shrink disproportionately under future climate change, potentially leading to high vulnerability for many of the species they contain.

Morphine pharmacokinetics and pharmacodynamics in preterm and term neonates: secondary results from the NEOPAIN trial

BACKGROUND

Relationships between plasma morphine concentrations and neonatal responses to endotracheal tube (ETT) suctioning are unknown in preterm neonates.

METHODS

Ventilated preterm neonates (n=898) from 16 centres were randomly assigned to placebo (n=449) or morphine (n=449). After an i.v. loading dose (100 microg kg(-1)), morphine infusions [23-26 weeks postmenstrual age (PMA) 10 microg kg(-1) h(-1); 27-29 weeks 20 microg kg(-1) h(-1); and 30-32 weeks 30 microg kg(-1) h(-1)] were established for a maximum of 14 days. Open-label morphine (20-100 microg kg(-1)) was given for pain or agitation. Morphine assay and neonatal response to ETT suctioning was measured at 20-28 and 70-76 h after starting the drug infusion and at 10-14 h after discontinuation of the study drug. The concentration-effect response was investigated using non-linear mixed effects models.

RESULTS

A total of 5119 data points (1598 measured morphine concentrations and 3521 effect measures) were available from 875 neonates for analysis. Clearance was 50% that of the mature value at 54.2 weeks PMA (CLmat(50)) and increased from 2.05 litre h(-1) 70 kg(-1) at 24 weeks PMA to 6.04 litre h(-1) 70 kg(-1) at 32 weeks PMA. The volume of distribution in preterm neonates was 190 litre 70 kg(-1) (CV 51%) and did not change with age. There was no relationship between morphine concentrations (range 0-440 microg litre(-1)) and heart rate changes associated with ETT suctioning or with the Premature Infant Pain Profile.

CONCLUSIONS

A sigmoid curve describing maturation of morphine clearance is moved to the right in preterm neonates and volume of distribution is increased compared with term neonates. Morphine does not alter the neonatal response to ETT suctioning.

The impact of modifiable family factors on glycemic control among youth with type 1 diabetes

OBJECTIVE

To identify modifiable family factors impacting glycemic control in youth with type 1 diabetes (T1DM) beyond the anticipated physical, developmental, and behavioral issues associated with adolescence.

STUDY DESIGN

In 153 youth (aged 8-16 yr) with T1DM duration of 6.3 +/- 3.5 yr and average hemoglobin A1c (HbA1c) of 8.4 +/- 1.4%, we examined modifiable family factors that might impact adherence to diabetes management and, in turn, influence glycemic control. Youth and parents completed surveys that assessed diabetes-specific knowledge, negative affect related to blood glucose monitoring (BGM), and parental-perceived burden of diabetes care. Clinician report and chart review provided data on growth, pubertal development, and diabetes management tasks. Glycemic control was measured as HbA1c.

RESULTS

In bivariate analyses, higher parental diabetes-specific knowledge (p < 0.0001), less youth negative affect related to BGM (p = 0.0005), and less parental-perceived burden (p = 0.0008) were associated with lower HbA1c. In a multivariate model controlling for demographic and diabetes-specific variables, these three factors remained independent and significant predictors of HbA1c (R(2) = 0.31 and p < 0.0001). Higher parental knowledge, less youth negative affect, and less parental burden predicted lower HbA1c, while youth knowledge and parental negative affect did not.

CONCLUSION

To attain optimal glycemic control, treatment programs for youth with T1DM should include ongoing efforts to reinforce parental knowledge of diabetes tasks, promote positive youth affect related to diabetes management, and acknowledge and reduce parental-perceived burden of diabetes management.

I.V. acetaminophen pharmacokinetics in neonates after multiple doses

BACKGROUND

Pharmacokinetics of an i.v. prodrug of acetaminophen (propacetamol) in neonates after repeat dosing are reported, with scant data for i.v. acetaminophen formulation.

METHODS

Neonates from an intensive care unit received 6-hourly prn i.v. acetaminophen dosed according to postmenstrual age (PMA): 28-32 weeks, 10 mg kg(-1); 32-36 weeks, 12.5 mg kg(-1); and > or =36 weeks, 15 mg kg(-1). A maximum of five blood samples for assay and liver function tests (LFTs) were collected. A one-compartment linear disposition model (zero-order input; first-order elimination) was used to describe time-concentration profiles using population modelling (NONMEM).

RESULTS

Fifty neonates, median (range) PMA 38.6 (32-45) weeks, mean (SD) weight 2.9 (0.7) kg, received a mean of 15 doses over a median 4 days with 189 serum acetaminophen and 231 LFT measurements. Standardized population parameter estimates for a term neonate were clearance (CL) 5.24 (CV 30.5%) litre h(-1) 70 kg(-1) and volume of distribution (V) 76 (29.6%) litre 70 kg(-1). CL increased with PMA from 4.4 litre h(-1) 70 kg(-1) at 34 weeks to 6.3 litre h(-1) 70 kg(-1) at 46 weeks. The presence of unconjugated hyperbilirubinaemia was associated with reduced CL: 150 micromol litre(-1) associated with 40% CL reduction. Acetaminophen concentrations between 10 and 23 mg litre(-1) at steady state are predicted after 15 mg kg(-1) 6-hourly for a neonate of PMA 40 weeks. Hepatic enzyme analysis of daily samples changed significantly for one patient whose alanine aminotransferase concentration tripled.

CONCLUSIONS

The parameter estimates are similar to those described for propacetamol. There was no evidence of hepatotoxicity. Unconjugated hyperbilirubinaemia impacts upon CL, dictating dose reduction.

Community structure in ichneumonid parasitoids at different spatial scales

The processes underlying parasitoid community structure are little known. Stochastic niche-apportionment models provide one route to underlying assemblage rules in this and other groups. Previous work has applied this approach to parasitoids found on single host species in single populations. However, parasitoid communities are known to extend across multiple hosts and scales. The patterns of relative abundances generated by five niche-apportionment models were compared to those observed in assemblages of two sub-families of the Ichneumonidae, the Diplazontinae and Pimplinae, at landscape and patch scales, Yorkshire, UK. Three of the five models produced patterns that were significantly different to the observed pattern for all taxonomic levels at both spatial scales. The Diplazontinae fit the random fraction (RF) model at the landscape scale in broadleaved woods. This suggests that hierarchical structuring and biotic interactions may play a role in the structuring of Diplazontinae assemblages at this scale. In contrast the Pimplinae fit the RF model only at the patch scale and only at one site. However, the Pimplini tribe (all chiefly parasitoids of Lepidoptera) fit the random assortment (RA) model at both the landscape and the patch scales, whilst the Ephialtini tribe (wide range of hosts) fit no model at either scale. The ecological interpretation of the RA model suggests that the Pimplini tribe is an unsaturated assemblage, where some of the total available resources are unused. Our results show, through the fit of mechanistic niche-apportionment models, that the processes that may structure ichneumonid parasitoid assemblages are not consistent across taxa and spatial scales.

Dietary behaviors predict glycemic control in youth with type 1 diabetes

OBJECTIVE

To investigate the association between dietary adherence and glycemic control among youth with type 1 diabetes.

RESEARCH DESIGN AND METHODS

We conducted a cross-sectional analysis of 119 youth aged 9-14 years (mean +/- SD 12.1 +/- 1.6 years) with diabetes duration > or =1 year (5.4 +/- 3.1 years). Dietary adherence was assessed using the Diabetes Self-Management Profile diet domain. Higher score defined greater dietary adherence. Glycemic control was determined by A1C.

RESULTS

Dietary adherence score was inversely correlated with A1C (r = -0.36, P < 0.0001). In a multivariate model (R(2) = 0.34, P < 0.0001), dietary adherence (P = 0.004), pump use (P = 0.03), and caregiver education (P = 0.01) were associated with A1C. A1C of youth in the lowest (9.0%) tertile of diet score was higher than A1C of youth in the middle (8.1%, P = 0.004) and upper (8.4%, P = 0.06) tertiles. Dietary adherence uniquely explained 8% of the variance in A1C in the model.

CONCLUSIONS

Greater dietary adherence was associated with lower A1C among youth with type 1 diabetes.

Insulin restriction and associated morbidity and mortality in women with type 1 diabetes

OBJECTIVE

To determine whether insulin restriction increases morbidity and mortality in women with type 1 diabetes.

RESEARCH DESIGN AND METHODS

This is an 11-year follow-up study of women with type 1 diabetes. A total of 234 women (60% of the original cohort) participated in the follow-up. Mean age was 45 years and mean diabetes duration was 28 years at follow-up. Mean BMI was 25 kg/m(2) and mean A1C was 7.9%. Measures of diabetes self-care behaviors, diabetes-specific distress, fear of hypoglycemia, psychological distress, and eating disorder symptoms were administered at baseline. At follow-up, mortality data were collected through state and national databases. Follow-up data regarding diabetes complications were gathered by self-report.

RESULTS

Seventy-one women (30%) reported insulin restriction at baseline. Twenty-six women died during follow-up. Based on multivariate Cox regression analysis, insulin restriction conveyed a threefold increased risk of mortality after controlling for baseline age, BMI, and A1C. Mean age of death was younger for insulin restrictors (45 vs. 58 years, P < 0.01). Insulin restrictors reported higher rates of nephropathy and foot problems at follow-up. Deceased women had reported more frequent insulin restriction (P < 0.05) and reported more eating disorder symptoms (P < 0.05) at baseline than their living counterparts.

CONCLUSIONS

Our data demonstrate that insulin restriction is associated with increased rates of diabetes complications and increased mortality risk. Mortality associated with insulin restriction appeared to occur in the context of eating disorder symptoms, rather than other psychological distress. We propose a screening question appropriate for routine diabetes care to improve detection of this problem.

Paracetamol (acetaminophen) pharmacodynamics: interpreting the plasma concentration

Interpretation of analgesic and antipyretic responses documented after paracetamol administration is confused because response is not directly related to concentration in the blood, but rather to an effect compartment. The effect compartment does not have real measurable concentrations, but concentrations equate approximately to those observed in the cerebrospinal fluid. A time delay exists before drug reaches the effect compartment, and the equilibration half-time between the central and effect compartment is described by a single first-order parameter (Teq or T(1/2)keo), reported to be approximately 1 h for paracetamol. Paediatric analgesic studies are limited because they have only explored postoperative pain after tonsillectomy or day-stay surgery. Other pain types and pain confounders have not been investigated. Adult studies are also similarly limited. Studies investigating antipyresis have not explored the maximum response, limiting the precision of any EC(50) estimate. The influence of the cyclical nature of fever or initial temperature is seldom accounted for in antipyretic studies. Target effect compartment concentrations of 5 mg/l for fever and 10 mg/l for pain do not seem unreasonable on the basis of current literature. Speed of onset may be shortened by giving a larger initial dose or improving absorption characteristics. Consequent plasma concentration achieved, differences in effect compartment equilibration times, and the shape of the effect compartment concentration-response curve help to explain differences between common analgesic/antipyretic drugs.

Mechanism-based concepts of size and maturity in pharmacokinetics

Growth and development can be investigated using readily observable demographic factors such as weight and age. Size is the primary covariate and can be referenced to a 70-kg person with allometry using a coefficient of 0.75 for clearance and 1 for volume. The use of these coefficients is supported by fractal geometric concepts and observations from diverse areas in biology. Fat free mass (FFM) might be expected to do better than total body weight when there are wide variations in fat affecting body composition. Clearance pathways develop in the fetus before birth. The use of postnatal age as a descriptor of maturation is unsatisfactory because birth may occur prematurely; therefore postmenstrual age is a superior predictor of elimination function. A sigmoid E(max) model (Hill equation) describes gradual maturation of clearance in early life leading to a mature adult clearance achieved at a later age.