Predictors of change in the neuropsychological profiles of children with type 1 diabetes 2 years after disease onset

Monitoring Glucose Concentrations in Children with Epilepsy on a Ketogenic Diet

Ketogenic diet (KD) and pulsatile dexamethasone therapy (PDT) are commonly used in the treatment of children with drug resistant epilepsy. Potential side effects of the KD are hypoglycemia, whereas PDT might lead to hyperglycemia. One practical option to measure glucose concentrations regularly is the flash glucose monitoring system (FGM). In this single-center study in Germany, two pediatric patients with epilepsy (age: 6.0 and 6.8 years) received FGM from the beginning of the KD over six months, in the year 2020, and one patient (9.8 years) was observed for one month on PDT and switched to the KD thereafter. Glucose concentrations were measured by using an FGM system and capillary blood measurement. Seizure frequency, changes in cognition, motor performance, social behavior, and sleep quality were evaluated. The mean hypoglycemia rate per day (65 mg/dL and lower) declined significantly in patient 1 and 2 after three months. Patient 3 showed in total seven hyperglycemic events during PDT. Patient 1 became seizure free. Improvement of attention and memory performance were reported. FGM during the KD as a treatment for drug resistant epilepsies in childhood is a practical option to explore and to avoid hypoglycemia during the KD and hyperglycemia during PDT.

Association between trajectory of severe hypoglycemia and dementia in patients with type 2 diabetes: A population-based study

Background

We aimed to investigate associations between exposure to various trajectories of severe hypoglycemic events and risk of dementia in patients with type 2 diabetes.

Methods

In 2002–2003, 677,618 patients in Taiwan were newly diagnosed as having type 2 diabetes. Among them, 35,720 (5.3%) experienced severe hypoglycemic events during the 3-year baseline period following diagnosis. All patients were followed from the first day after baseline period to the date of dementia diagnosis, death, or the end of 2011. A group-based trajectory model was used to classify individuals with severe hypoglycemic events during the baseline period. Cox proportional hazard models with the competing risk method were used to relate dementia risk to various severe hypoglycemia trajectories.

Results

After a median follow-up 6.70 and 6.10 years for patients with and without severe hypoglycemia at baseline, respectively, 1,952 (5.5%) individuals with severe hypoglycemia and 23,492 (3.7%) without developed dementia during follow-up, for incidence rates of 109.80 and 61.88 per 10,000 person-years, respectively. Four groups of severe hypoglycemia trajectory were identified with a proportion of 18.06%, 33.19%, 43.25%, and 5.50%, respectively, for Groups 1 to 4. Groups 3 (early manifestation but with later decrease) and 4 (early and sustained manifestation) were associated with a significantly increased risk of dementia diagnosis, with a covariate-adjusted subdistribution hazard ratio of 1.22 (95% confidence interval, 1.14–1.31) and 1.25 (95% confidence interval, 1.02–1.54), respectively.

Conclusion

Our analysis highlighted that early manifestation of severe hypoglycemic events may contribute more than does late manifestation to the risk of dementia among individuals newly diagnosed as having type 2 diabetes.

Priorities in the Interdisciplinary Approach of Specific Learning Disorders (SLD) in Children with Type I Diabetes Mellitus (T1DM). From Theory to Practice

BACKGROUND

A considerable endeavor had taken place in order to understand the associated challenges for children and adolescents with Specific Learning Disorder (SLD) and Type 1 Diabetes Mellitus (T1DM) but also in order to describe the necessary skills and approaches that the care givers have to develop to assist both children and parents. (1) Aim: The aim of this review is twofold. Firstly, to highlight the T1DM's potential impact on psychological well-being, on cognitive functioning and on school performance in children and adolescents who confront SLD. Secondly, to discuss the necessity of a multidiscipline approach of poor school performance in students with SLD and T1DM, presenting the serious contribution of care providers: (a) parents/carers in the family setting, (b) teachers and psychologists in the school setting and (c) health specialists (pediatricians, nutricians, nurses, child psychiatrists and psychologists) in the medical setting. (2) Methods: In this narrative literature review of 12 selected articles, each one studies a special aspect of approach, during the diagnosis and the treatment of individuals with T1DM and SLD. The review concerns the arising problems and difficulties in the adherence to diagnosis, the management of insulin, the mental and physical wellbeing, the school performance, the cognitive functioning and learning difficulties of patients. We tried to synthesize an interdisciplinary approach that involves collaboration between family, school and medical frame; facilitating children's and adolescents' difficulties management, as well as parent and teacher involvement during the intervention implementation. (3) Results: The main issues of concern were examined through the available literature, as different factors had to be re-examined in the previous studies, regarding the potential impact of T1DM in cognitive and psychological functioning, as well as the effects of the intervention/approach/treatment of children and adolescents with SLD and T1DM. (4) Conclusions: Although T1DM diagnosis and demanding treatment are a heavy burden for children and their families, T1DM may or may not be associated with a variety of academic and psychological outcomes. Despite the variability of the reviewed research design quality, it was clearly defined that the impact of T1DM is not uniform across educational and mental variables. Strengthening the children's physical, psychological and social wellbeing is an especially important factor, as it facilitates the insulin's management as well as the learning difficulties. This is possible by supporting the parental and teacher involvement in the intervention process. This review highlights the need to reduce the distance between theory/research and practice, in some of the proposed areas in this field of knowledge.

Relationships between Early Nutrition, Illness, and Later Outcomes among Infants Born Preterm with Hyperglycemia

OBJECTIVE

To evaluate the effects of hyperglycemia on body composition and neurodevelopment, and how early nutrition and illness modify these relationships in infants born preterm.

STUDY DESIGN

Prospective data were collected from infants born <32 weeks of gestational age (N = 97), including inpatient days of hyperglycemia (blood glucose >150 mg/dL) and nutrient intake. Body composition was measured at discharge and 4 months' postmenstrual age (PMA). Bayley Scales of Infant Development III (BSID-III) were administered at 12 months' PMA. Linear regression analysis was performed, adjusting for birth gestational age. Associations between hyperglycemia, body composition, and BSID-III were analyzed in models accounting for first-week nutrition and early illness severity via Score for Neonatal Acute Physiology-II.

RESULTS

Mean birth gestational age was 27.8 (SD 2.4) weeks. Hyperglycemia occurred in 48.5% of infants. Hyperglycemia for ≥5 days was negatively associated with fat mass and fat free mass z scores at discharge, and fat free mass z score at 4 months' PMA (P < .05 all). Hyperglycemia for ≥5 days was negatively associated with cognition, language, and motor scores on the BSDI at 12 months (P ≤ .01 all). Associations with body composition and BSID-III were diminished when models included first week nutrition yet remained unchanged when illness severity was included.

CONCLUSIONS

In infants <32 weeks, ≥5 days of hyperglycemia is associated with decreased lean mass at 4 months' PMA and poorer neurodevelopmental outcome at 12 months' PMA. These associations may be mediated by decreased first week nutrition, potentially related to reduced glucose infusion rate for management of hyperglycemia.

A systematic review of the effect of prior hypoglycaemia on cognitive function in type 1 diabetes

BACKGROUND

The effect of prior hypoglycaemia on cognitive function in type 1 diabetes is an important unresolved clinical question. In this systematic review, we aimed to summarize the studies exploring the impact of prior hypoglycaemia on any aspect of cognitive function in type 1 diabetes.

METHODS

We used a multidatabase search platform Healthcare Database Advanced Search to search Medline, PubMed, EMBASE, EMCARE, CINAHL, PsycINFO, BNI, HMIC, and AMED from inception until 1 May 2019. We included studies on type 1 diabetes of any age. The outcome measure was any aspect of cognitive function.

RESULTS

The 62 studies identified were grouped as severe hypoglycaemia (SH) in childhood (⩽18 years) and adult-onset (>18 years) diabetes, nonsevere hypoglycaemia (NSH) and nocturnal hypoglycaemia (NH). SH in early childhood-onset diabetes, especially seizures and coma, was associated with poorer memory (verbal and visuospatial), as well as verbal intelligence. Among adult-onset diabetes, SH was associated with poorer cognitive performance in the older age (>55 years) group only. Early versus late exposure to SH had a significant association with cognitive dysfunction (CD). NSH and NH did not have any significant association with CD, while impaired awareness of hypoglycaemia was associated with poorer memory and cognitive-processing speeds.

CONCLUSION

The effect of SH on cognitive function is age dependent. Exposure to SH in early childhood (<10 years) and older age groups (>55 years) was associated with a moderate effect on the decrease in cognitive function in type 1 diabetes [PROSPERO ID: CRD42019141321].

Priming effect in children with Type 1 Diabetes Mellitus

Previous studies have evidenced cognitive difficulties across various domains in Type 1 Diabetes Mellitus (T1DM) children, but the implicit memory system has not yet been systematically explored.Taking into account that the interplay between memory and perception may be modulated by the semantic category of the stimuli and their salience, we explored explicit and implicit memory using both object and food stimuli to verify whether for T1DM children there is a feebleness in performing the function of memory as a function of the stimuli used.Eighteen T1DM children and 47 healthy children performed an explicit recognition task in which they were requested to judge whether the presented image had already been shown ("old") or not ("new") and an identification priming task in which they were asked to name new and old pictures presented at nine ascending levels of spatial filtering.Results did not reveal any differences between controls and T1DM children in the explicit memory recognition task, whereas some differences between the two groups were found in the identification priming task. In T1DM children, the priming effect was observed only for food images.The dissociation between implicit and explicit memory observed in children with diabetes seems to be modulated by the category of the stimuli, and these results underscore the relevance of taking into account this variable when exploring cognitive functions.

Psychosocial aspects of diabetes management: dilemma of diabetes distress

Diabetes mellitus (DM) is a debilitating chronic illness with complex pathophysiological, psychological, and quality of life (QoL) implications creating a constant state of turbulence. Some of these interconnections are apparent to healthcare providers and are easily addressed in a routine diabetic clinical care. However, a large number of these hidden factors that interplay with each other and impact on the physical outcomes of DM goes unnoticed by health care providers. This is a frustrating and lonely predicament for DM patients making it very difficult for them to manage their illness well. At times these patients are mislabeled as "difficult patients". In other cases they are considered to have and unnecessarily treated for psychiatric illness like depression, other mood or anxiety spectrum disorders which they may not need. In recent years clinical researcher are making strides in understanding the emotional distress a DM patient may feel and the factors contributing or perpetuating diabetes distress. This article focuses on understanding the diabetes distress and how it impacts our patients, how to screen, assess, treat and eventually prevent it from happening. The paper also attempt to bring out the major differences between diabetes distress and common psychiatric comorbidities of DM including but not limiting to major depressive disorder and other depression spectrum disorders.

Diabetic Ketoacidosis at Diagnosis of Type 1 Diabetes Predicts Poor Long-term Glycemic Control

OBJECTIVE

This study tested the hypothesis that diabetic ketoacidosis (DKA) at diagnosis of type 1 diabetes in children predicts poor long-term glycemic control independently of established risk factors.

RESEARCH DESIGN AND METHODS

This was a prospective cohort study of 3,364 Colorado residents diagnosed with type 1 diabetes before 18 years of age, in 1998-2012, and monitored for up to 15 years. Of those, 1,297 (39%) had DKA at diagnosis (blood glucose >250 mg/dL, and venous pH <7.3 or bicarbonate <15 mEq/L). Severity of DKA was further classified as mild/moderate (pH 7.10-7.29 or bicarbonate 5-14 mEq/L) or severe (pH <7.10 or bicarbonate <5 mEq/L). HbA_1c levels were measured an average of 2.8 times/year (median 20 HbA_1c values/patient). A linear mixed model was used to examine the effect of DKA on long-term HbA_1c levels, adjusting for age, race/ethnicity, sex, family history of diabetes, health insurance, and insulin pump use.

RESULTS

DKA at diagnosis predicted persistently elevated HbA_1c levels. Compared with children without DKA, HbA_1c tracked 1.4% (15.3 mmol/mol) higher in those with severe DKA (P < 0.0001) and 0.9% (9.8 mmol/mol) higher in those with mild/moderate DKA at diagnosis (P < 0.0001). These effects were independent of ethnic minority status or lack of health insurance at diagnosis that predicted higher HbA_1c by 0.5% (5.5 mmol/mol; P < 0.0001) and 0.2% (2.2 mmol/mol; P < 0.0001), respectively. Insulin pump use or having a parent or sibling with type 1 diabetes predicted lower long-term HbA_1c by, respectively, 0.4% (4.4 mmol/mol; P < 0.0001) and 0.2% (2.2 mmol/mol; P = 0.01).

CONCLUSIONS

DKA at diagnosis of type 1 diabetes in children predicts poor long-term glycemic control, independent of demographic and socioeconomic factors.

A longitudinal investigation of cognitive function in children and adolescents with type 1 diabetes mellitus

OBJECTIVE

Cross-sectional studies find altered cognition in youth with type 1 diabetes mellitus (T1DM). However, few longitudinal studies have examined the trajectories of their cognitive performance over time. The aims of this study were to explore longitudinal change in cognitive function in youth with T1DM as compared with nondiabetic sibling controls, and how glycemic control and age of onset influence cognitive performance over time.

METHODS

We assessed crystallized intelligence, visual-spatial ability, delayed memory, and processing speed at 3 time points using the same cognitive tasks in youth with T1DM and sibling controls. Hierarchical linear modeling examined relationships between diabetes, hyperglycemia (HbA1c values), age of onset, and cognition over 5.5 y.

RESULTS

Youth with diabetes performed worse than controls on visual-spatial ability and memory tasks over time, and did not improve as much in processing speed. Greater hyperglycemia was associated with lower crystallized intelligence and slower processing speed but better memory across all time points. There was a stronger negative relationship between hyperglycemia and visual-spatial ability for youth with earlier compared with later onset diabetes. Importantly, within-person decreases in hyperglycemia between time points were associated with improved visual-spatial ability and faster processing speed.

CONCLUSIONS

On average, differences in cognitive function between youth with T1DM and nondiabetic relatives are maintained or increase during childhood and adolescence. Hyperglycemia and age of onset can have negative effects on the developmental trajectories of cognitive processes in youth with T1DM. However, treatments that lower hyperglycemia may lead to improved cognitive function in youth with T1DM.

Cognition and Type 1 Diabetes in Children and Adolescents

IN BRIEF In children and adolescents with type 1 diabetes, exposure to glycemic extremes (severe hypoglycemia, chronic hyperglycemia, and diabetic ketoacidosis) overlaps with the time period of most active brain and cognitive development, leading to concerns that these children are at risk for cognitive side effects. This article summarizes the existing literature examining the impact of glycemic extremes on cognitive function and brain structure in youth with type 1 diabetes and points out areas for future research.

Longitudinal Evaluation of Cognitive Functioning in Young Children with Type 1 Diabetes over 18 Months

OBJECTIVES

Decrements in cognitive function may already be evident in young children with type 1 diabetes (T1D). Here we report prospectively acquired cognitive results over 18 months in a large cohort of young children with and without T1D.

METHODS

A total of 144 children with T1D (mean HbA1c: 7.9%) and 70 age-matched healthy controls (mean age both groups 8.5 years; median diabetes duration 3.9 years; mean age of onset 4.1 years) underwent neuropsychological testing at baseline and after 18-months of follow-up. We hypothesized that group differences observed at baseline would be more pronounced after 18 months, particularly in those T1D patients with greatest exposure to glycemic extremes.

RESULTS

Cognitive domain scores did not differ between groups at the 18 month testing session and did not change differently between groups over the follow-up period. However, within the T1D group, a history of diabetic ketoacidosis (DKA) was correlated with lower Verbal IQ and greater hyperglycemia exposure (HbA1c area under the curve) was inversely correlated to executive functions test performance. In addition, those with a history of both types of exposure performed most poorly on measures of executive function.

CONCLUSIONS

The subtle cognitive differences between T1D children and nondiabetic controls observed at baseline were not observed 18 months later. Within the T1D group, as at baseline, relationships between cognition (Verbal IQ and executive functions) and glycemic variables (chronic hyperglycemia and DKA history) were evident. Continued longitudinal study of this T1D cohort and their carefully matched healthy comparison group is planned.

Long-term Outcomes in Youths with Diabetes Mellitus

In this article, the author reviews the long-term outcomes and their precursors of type 1 diabetes starting in youth. The author also contrasts the changing incidence of these long-term complications as we have moved from the pre-Diabetes Control and Complications Trial (DCCT) to the post-DCCT standard of care and reviews the emerging data related to complications in youths with type 2 diabetes. Finally, the author reviews the recent understanding related to the effects of diabetes on the brain and cognition.

Evaluation of Pre-Treatment and Post-Treatment S100B, Oxidant and Antioxidant Capacity in Children with Diabetic Ketoacidosis

OBJECTIVE

The study aimed to evaluate the pre-treatment and post-treatment oxidant capacity, antioxidant capacity and S100B protein levels in cases of diabetic ketoacidosis (DKA).

METHODS

The study included 49 pediatric patients diagnosed with DKA and a control group comprising 49 healthy children. Blood samples were obtained after confirmation of the DKA diagnosis and also after treatment. S100B, total oxidant (TOL) and total antioxidant levels (TAL) were measured and the oxidative stress index (OSI) was calculated.

RESULTS

When the pre-treatment and post-treatment values of patients with DKA were compared with those of the healthy control group, the S100B level, TOL, TAL and OSI were found to be significantly higher in the diabetes group (p<0.001). Pre-treatment TOL and TAL were also significantly higher than post-treatment levels (p<0.001), while no statistically significant difference was found in the S100B levels or the OSI (p>0.05).

CONCLUSION

We believe that long-term exposure to high blood glucose concentrations leads to an increase in TOL in patients with DKA and that the neurotransmitter changes that develop in response to this exposure lead to an increase in S100B levels, which is an indicator of neuronal damage.

Diabetes Mellitus, Cognitive Impairment, and Traditional Chinese Medicine

Diabetes mellitus (DM) is a metabolic disorder affecting a large number of people worldwide. Numerous studies have demonstrated that DM can cause damage to multiple systems, leading to complications such as heart disease, cancer, and cerebrovascular disorders. Numerous epidemiological studies have shown that DM is closely associated with dementia and cognition dysfunction, with recent research focusing on the role of DM-mediated cerebrovascular damage in dementia. Despite the therapeutic benefits of antidiabetic agents for the treatment of DM-mediated cognitive dysfunction, most of these pharmaceutical agents are associated with various undesirable side-effects and their long-term benefits are therefore in doubt. Early evidence exists to support the use of traditional Chinese medicine (TCM) interventions, which tend to have minimal toxicity and side-effects. More importantly, these TCM interventions appear to offer significant effects in reducing DM-related complications beyond blood glucose control. However, more research is needed to further validate these claims and to explore their relevant mechanisms of action. The aims of this paper are (1) to provide an updated overview on the association between DM and cognitive dysfunction and (2) to review the scientific evidence underpinning the use of TCM interventions for the treatment and prevention of DM-induced cognitive dysfunction and dementia.

Cognitive functioning in young children with type 1 diabetes

The aim of this study was to assess cognitive functioning in children with type 1 diabetes (T1D) and examine whether glycemic history influences cognitive function. Neuropsychological evaluation of 216 children (healthy controls, n = 72; T1D, n = 144) ages 4-10 years across five DirecNet sites. Cognitive domains included IQ, Executive Functions, Learning and Memory, and Processing Speed. Behavioral, mood, parental IQ data, and T1D glycemic history since diagnosis were collected. The cohorts did not differ in age, gender or parent IQ. Median T1D duration was 2.5 years and average onset age was 4 years. After covarying age, gender, and parental IQ, the IQ and the Executive Functions domain scores trended lower (both p = .02, not statistically significant adjusting for multiple comparisons) with T1D relative to controls. Children with T1D were rated by parents as having more depressive and somatic symptoms (p < .001). Learning and memory (p = .46) and processing speed (p = .25) were similar. Trends in the data supported that the degree of hyperglycemia was associated with Executive Functions, and to a lesser extent, Child IQ and Learning and Memory. Differences in cognition are subtle in young children with T1D within 2 years of onset. Longitudinal evaluations will help determine whether these findings change or become more pronounced with time.

Glycemic extremes in youth with T1DM: the structural and functional integrity of the developing brain

The adult brain accounts for a disproportionally large percentage of the body’s total energy consumption (1). However, during brain development,energy demand is even higher, reaching the adult rate by age 2 and increasing to nearly twice the adult rate by age 10, followed by gradual reduction toward adult levels in the next decade (1,2). The dramatic changes in brain metabolism occurring over the first two decades of life coincide with the initial proliferation and then pruning of synapses to adult levels.The brain derives its energy almost exclusively from glucose and is largely driven by neuronal signaling, biosynthesis, and neuroprotection (3–6).Glucose homeostasis in the body is tightly regulated by a series of hormones and physiologic responses. As a result, hypoglycemia and hyperglycemia are rare occurrences in normal individuals, but they occur commonly inpatients with type 1 diabetes mellitus (T1DM) due to a dysfunction of peripheral glucose-insulin-glucagon responses and non-physiologic doses of exogenous insulin, which imperfectly mimic normal physiology. These extremes can occur more frequently in children and adolescents with T1DM due to the inadequacies of insulin replacement therapy, events leading to the diagnosis [prolonged untreated hyperglycemia and diabetic ketoacidosis (DKA)], and to behavioral factors interfering with optimal treatment. When faced with fluctuations in glucose supply the metabolism of the body and brain change dramatically, largely to conserve resources and, at a cost to other organs, to preserve brain function (7). However,if the normal physiological mechanisms that prevent these severe glucose fluctuations and maintain homeostasis are impaired, neuronal function and potentially viability can be affected (8–11).

Feasibility of prolonged continuous glucose monitoring in toddlers with type 1 diabetes

OBJECTIVE

To examine the feasibility of continuous glucose monitoring (CGM) use in very young children with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

Twenty-three children less than 4 yr of age with T1D were provided with a FreeStyle Navigator(®) (n = 21) or a Paradigm(®) (n = 2) CGM device. At baseline, mean age was 3.0 ± 0.8 yr, mean hemoglobin A1c (HbA1c) was 8.0 ± 0.8%, 10 were using an insulin pump and 13 were on multiple daily injections. CGM use was evaluated over a 6-month period.

RESULTS

Three children dropped out of the study before the end of 6 months. Among the 20 children who completed 6 months of follow-up, CGM use in month 6 was ≥6 d/wk in 9 (45%), 4 ≤ 6 d/wk in 2 (10%), and <4 d/wk in 9 (45%). Skin reactions were minimal. Although there was no detectable change in mean HbA1c between baseline and 6 months (7.9 and 8.0%, respectively), there was a high degree of parental satisfaction with CGM as measured on the CGM satisfaction scale questionnaire. A high percentage of glucose values were in the hyperglycemic range, and biochemical hypoglycemia was infrequent.

CONCLUSION

More than 40% of very young children were able to safely use CGM on a near-daily basis after 6 months. CGM demonstrated frequent hyperglycemic excursions, with a large variability in glucose readings. Although improvement in glycemic control was not detected in the group as a whole, parental satisfaction with CGM was high.

The effect of recurrent severe hypoglycemia on cognitive performance in children with type 1 diabetes: a meta-analysis

The purpose of this study was to investigate the existence and extent of cognitive impairment in type 1 diabetic children with episodes of recurrent severe hypoglycemia, using meta-analysis to synthesize data across studies. The meta-analysis sample included: 441 children with diabetes and recurrent severe hypoglycemia, 560 children with diabetes and without recurrent severe hypoglycemia. Overall, children with type 1 diabetes and recurrent severe hypoglycemia had slightly lower performance than diabetic children without severe hypoglycemia, only in some cognitive domains: intelligence, memory, learning, and verbal fluency/language. Greater impairment was found in memory and learning. No impairment was found for motor speed. Our results seem to confirm the hypothesis that recurrent severe hypoglycemia has a selective negative effect on the children's cognitive functions. However, these results must be considered with caution taking into account factors such as small sample sizes, the different definitions of severe hypoglycemia, and the variety of neuropsychological tests used.

Management of nonpsychiatric medical conditions presenting with psychiatric manifestations

There is a significant dilemma when underlying medical disorders present as psychiatric conditions. It is important to identify the medical condition because treatment and management strategies need to be directed to the presenting symptoms and also to the underlying medical condition for successful treatment of the patient. Some systemic disorders present with psychiatric manifestations more often than others. The pattern of psychiatric disturbance seen may be specific for a particular medical disorder but may also be varied. Many drug formulations and medications also may produce psychiatric presentations. This article considers the management of nonpsychiatric medical conditions presenting with psychiatric manifestations.

Pharmacologic amelioration of severe hypoglycemia-induced neuronal damage

Hypoglycemia is a common complication for insulin treated people with diabetes. Severe hypoglycemia, which occurs in the setting of excess or ill-timed insulin administration, has been shown to cause brain damage. Previous pre-clinical studies have shown that memantine (an N-methyl-d-aspartate receptor antagonist) and erythropoietin can be neuroprotective in other models of brain injury. We hypothesized that these agents might also be neuroprotective in response to severe hypoglycemia-induced brain damage. To test this hypothesis, 9-week old, awake, male Sprague-Dawley rats underwent hyperinsulinemic (0.2 U kg(-1)min(-1)) hypoglycemic clamps to induce severe hypoglycemia (blood glucose 10-15 mg/dl for 90 min). Animals were randomized into control (vehicle) or pharmacological treatments (memantine or erythropoietin). One week after severe hypoglycemia, neuronal damage was assessed by Fluoro-Jade B and hematoxylin and eosin staining of brain sections. Treatment with both memantine and erythropoietin significantly decreased severe hypoglycemia-induced neuronal damage in the cortex by 35% and 39%, respectively (both p<0.05 vs. controls). These findings demonstrate that memantine and erythropoietin provide a protective effect against severe hypoglycemia-induced neuronal damage.

Short and long term outcome of neonatal hyperglycemia in very preterm infants: a retrospective follow-up study

Background

Hyperglycemia in premature infants is associated with increased morbidity and mortality, but data on long-term outcome are limited. We investigated the effects of neonatal hyperglycemia (blood glucose ≥ 10 mmol/l, treated with insulin for ≥ 12 hours) on growth and neurobehavioral outcome at 2 years of age.

Methods

Retrospective follow-up study at 2 years of age among 859 infants ≤32 weeks of gestation admitted to a tertiary neonatal center between January 2002 and December 2006. Thirty-three survivors treated with insulin for hyperglycemia and 63 matched controls without hyperglycemia were evaluated at a corrected age of 2 years. Outcome measures consisted of growth (weight, length, and head circumference) and neurological and behavioural development.

Results

66/859 (8%) infants ≤ 32 weeks of gestation developed hyperglycemia. Mortality during admission was 27/66 (41%) in the hyperglycemia group versus 62/793 (8%) in those without hyperglycemia (p < 0.001). Mortality was higher in infants with hyperglycemia with a birth weight ≤1,000 gram (p = 0.005) and/or gestational age of 24-28 weeks (p = 0.009) than in control infants without hyperglycemia. Sepsis was more prominent in infants with hyperglycemia and a birth weight of >1,000 gram (p = 0.002) and/or gestational age of 29-32 weeks (p = 0.009) than in control infants without hyperglycemia. Growth at 2 years of age was similar, but neurological and behavioural development was more frequently abnormal among those with neonatal hyperglycemia (p = 0.036 and 0.021 respectively).

Conclusions

Mortality was higher in very preterm infants with hyperglycemia treated with insulin during the neonatal period. At 2 years of age survivors showed normal growth, but a higher incidence of neurological and behavioural problems. Better strategies to manage hyperglycemia may improve outcome of very preterm infants.

Cognitive functions and glycemic control in children and adolescents with type 1 diabetes

BACKGROUND

The relationship between metabolic control and cognitive function in adolescents with type 1 diabetes (DM type 1) is not clear. We compared the quality of glycemic control (GC) and cognitive measures in adolescents with DM type 1 to find out if the quality of diabetes management is related to cognitive impairment.

METHOD

We assessed executive functions (EFs) and other neuropsychological and psychosocial variables in 70 adolescent patients with DM type 1 and 20 age-matched controls. Patients were divided into two groups according to their last hemoglobin A1c (HbA1c): acceptable (HbA1c 5.9-8.0%, mean 6.9%, 36 patients, mean age 14 years) and non-optimal (HbA1c 8.2-11.6%, mean 9.3%, 34 patients, mean age 15.6 years).

RESULTS

We found impaired EFs, mainly problems of concept formation (p=0.038), cognitive flexibility (p=0.011) and anticipation (p=0.000), in the patients with DM type 1. Both groups did not differ in intelligence, most assessed EFs and adjustment to chronic illness (Youth Self-Report; YSR). Younger patients (<15 years) were cognitively less flexible. GC was worse in older patients and in patients with longer duration of the disease. We also found significant differences between patients with diabetes and controls concerning somatic complaints, internalizing problems (Child Behavior Checklist; CBCL) and social activity (CBCL and YSR).

CONCLUSIONS

DM type 1 is associated with cognitive deficits in adolescents independent of the quality of metabolic control and the duration of the disease. These deficits are probably related to the disease, especially in patients with early-onset diabetes.

Clinical evaluation of a noninvasive alarm system for nocturnal hypoglycemia

BACKGROUND

The aim of this study was to evaluate the performance of a prototype noninvasive alarm system (HypoMon) for the detection of nocturnal hypoglycemia. A prospective cohort study evaluated an alarm system that included a sensor belt, a radio frequency transmitter for chest belt signals, and a receiver. The receiver incorporated integrated "real-time" algorithms designed to recognize hypoglycemia "signatures" in the physiological parameters monitored by the sensor belt.

METHODS

Fifty-two children and young adults with type 1 diabetes mellitus (T1DM) participated in this blinded, prospective, in-clinic, overnight study. Participants had a mean age of 16 years (standard deviation 2.1, range 12-20 years) and were asked to follow their normal meal and insulin routines for the day of the study. Participants had physiological parameters monitored overnight by a single HypoMon system. Their BG levels were also monitored overnight at regular intervals via an intravenous cannula and read on two independent Yellow Springs Instruments analyzers. Hypoglycemia was not induced by any manipulations of diabetes management, rather the subjects were monitored overnight for "natural" occurrences of hypoglycemia. Performance analyses included comparing HypoMon system alarm times with allowed time windows associated with each hypoglycemic event.

RESULTS

The primary recognition algorithm in the prototype alarm system performed at a level consistent with expectations based on prior user surveys. The HypoMon system correctly recognized 8 out of the 11 naturally occurring overnight hypoglycemic events and falsely alarmed on 13 out of the remaining 41 normal nights [sensitivity 73% (8/11), specificity 68% (28/41), positive predictive value 38%,negative predictive value 90%].

CONCLUSION

The prototype HypoMon shows potential as an adjunct method for noninvasive overnight monitoring for hypoglycemia events in young people with T1DM.

Type 1 diabetes is associated with alexithymia in nondepressed, non-mentally ill diabetic patients: a case-control study

OBJECTIVE

Alexithymia refers to difficulty in identifying and expressing emotions, and it is a characteristic common to several psychiatric and medical conditions, including autoimmune disorders. Type 1 diabetes (T1D) is an autoimmune disorder with increased psychiatric comorbidity. Previously reported associations between alexithymia and T1D may have been confounded by the presence of depression. The central aim of this study was to examine alexithymia levels in psychiatrically uncomplicated T1D outpatients with that of nondiabetic controls.

METHODS

Ninety-six T1D patients without any DSM-IV Axis I diagnoses and 105 age- and sex-matched healthy controls entered the study. Alexithymia and depressive symptoms were assessed with the Toronto Alexithymia Scale (TAS-20) and the Beck Depression Inventory (BDI-21), respectively. Multivariate regression models were used to evaluate the association of alexithymia with the presence of diabetes, duration of diabetes, diabetes control, parameters of treatment intensification, and diabetic complications.

RESULTS

T1D was positively associated with the TAS-20 "identifying feelings" (beta coefficient=2.64, P=.003) and "externally oriented thinking" (beta coefficient=1.73, P=.011) subscales. The prevalence of overall alexithymia (TAS-20 total score, > or =60) was 22.2% in T1D patients and 7.6% in the controls (OR, 4.6; 95% CI, 1.7-12.8). TAS-20 scores were positively associated with diabetes duration and negatively with treatment intensification parameters.

CONCLUSIONS

Alexithymia is higher in psychiatrically uncomplicated T1D patients than in healthy controls even after adjustment for confounding depressive symptoms; it is greater with longer diabetes duration and is associated with some reduced parameters of treatment intensification but not with worse outcome in terms of glycemic control or somatic complications.

Diabetes increases brain damage caused by severe hypoglycemia

Insulin-induced severe hypoglycemia causes brain damage. The hypothesis to be tested was that diabetes portends to more extensive brain tissue damage following an episode of severe hypoglycemia. Nine-week-old male streptozotocin-diabetic (DIAB; n = 10) or vehicle-injected control (CONT; n = 7) Sprague-Dawley rats were subjected to hyperinsulinemic (0.2 U.kg(-1).min(-1)) severe hypoglycemic (10-15 mg/dl) clamps while awake and unrestrained. Groups were precisely matched for depth and duration (1 h) of severe hypoglycemia (CONT 11 +/- 0.5 and DIAB 12 +/- 0.2 mg/dl, P = not significant). During severe hypoglycemia, an equal number of episodes of seizure-like activity were noted in both groups. One week later, histological analysis demonstrated extensive neuronal damage in regions of the hippocampus, especially in the dentate gyrus and CA1 regions and less so in the CA3 region (P < 0.05), although total hippocampal damage was not different between groups. However, in the cortex, DIAB rats had significantly (2.3-fold) more dead neurons than CONT rats (P < 0.05). There was a strong correlation between neuronal damage and the occurrence of seizure-like activity (r(2) > 0.9). Separate studies conducted in groups of diabetic (n = 5) and nondiabetic (n = 5) rats not exposed to severe hypoglycemia showed no brain damage. In summary, under the conditions studied, severe hypoglycemia causes brain damage in the cortex and regions within the hippocampus, and the extent of damage is closely correlated to the presence of seizure-like activity in nonanesthetized rats. It is concluded that, in response to insulin-induced severe hypoglycemia, diabetes uniquely increases the vulnerability of specific brain areas to neuronal damage.

Prevalence of structural central nervous system abnormalities in early-onset type 1 diabetes mellitus

OBJECTIVE

To characterize the effects of severe hypoglycemia on the developing brain in children with early-onset type 1 diabetes mellitus (T1DM).

STUDY DESIGN

Children diagnosed with T1DM before age 6 years were studied. Those with prospectively monitored severe hypoglycemia (coma/seizure; n = 32) were compared with age-matched peers (n = 30) with no history of such events using magnetic resonance imaging. Glycemic control (evaluated based on glycated hemoglobin [HbA(lc)] level), episodes of diabetic ketoacidosis (DKA), and clinical variables were monitored continuously since diagnosis in all subjects.

RESULTS

Mean HbA(lc) from diagnosis and the duration of T1DM were similar in those with and without a history of severe hypoglycemia (9.0% +/- 0.9% vs 8.8% +/- 0.9%; 7.2 +/- 2.7 years vs 6.7 +/- 2.3 years). A high prevalence of central nervous system (CNS) structural abnormalities was detected (29%), and mesial temporal sclerosis (MTS) was detected in 16% of the total sample (n = 62). The presence of MTS was not associated with a history of severe hypoglycemia or DKA. Analysis of brain matter volumes suggested relatively less gray matter density in those subjects with a history of severe hypoglycemia.

CONCLUSIONS

Early age of onset of T1DM per se is associated with a high incidence of CNS abnormalities, particularly MTS, suggesting hippocampal damage. Early-onset severe hypoglycemia may have an effect on gray matter volume.

Neuro-cognitive performance in children with type 1 diabetes--a meta-analysis

OBJECTIVE

To conduct meta-analyses of neuropsychological performance in young people with type 1 diabetes.

METHODS

Meta-analysis of 24 studies. Studies published between 1980 and 2005 were identified. The inclusion criteria were: young people who were < or =19 years of age with type 1 diabetes, a case-control design and standardized neuropsychological tests of seven cognitive domains.

RESULTS

Diabetes was statistically associated with poorer performance on visuospatial ability (d = -0.29), motor speed (d = -0.26) and writing (d = -0.28), on sustained attention (d = -0.21) and reading (d = -0.23). Smaller effects were identified on full IQ (d = -0.14), on performance (d = -0.18) and verbal IQ (d = -0.15). Severe hypoglycemia was linked to deficits in short-term verbal memory (d = -0.14; Confidence Interval: -0.318, 0.024; p =.04).

CONCLUSIONS

This meta-analysis indicates that children with type 1 diabetes have mild cognitive impairments and subtly reduced overall intellectual functioning.

Effects of prior hypoglycemia and hyperglycemia on cognition in children with type 1 diabetes mellitus

OBJECTIVE

Despite the general consensus that youth with type 1 diabetes mellitus (T1DM) can experience modest cognitive impairment, debate continues over the role of severe hypoglycemia (Hypo) and/or hyperglycemia (Hyper) in producing such impairment. Our aim was to determine how Hypo and Hyper experienced during brain development predict patterns of subsequent cognitive performance in youth with T1DM.

METHODS

We tested youth aged 5-16 yr (T1DM, n = 117; non-diabetic sibling controls, n = 58) on cognitive tasks (verbal and spatial intelligence, verbal and spatial memory, and processing speed). T1DM participants were categorized as having experienced 0, 1-2, or 3 or more (3+) Hypo episodes, as having their first Hypo episode before or after 5 yr of age and as having early (before age 5) or late (after age 5) diabetes onset. Hyper exposure was estimated with median hemoglobin A1c, adjusted for diabetes duration for each subject.

RESULTS

The group with T1DM had lower estimated verbal intelligence than sibling controls. Within the T1DM group, verbal intelligence was reduced with increased exposure to Hyper, not to Hypo. In contrast, spatial intelligence and delayed recall were reduced only with repeated Hypo, particularly when Hypo episodes occurred before the age of 5 yr. Age of onset did not explain these results.

CONCLUSIONS

Hypo and Hyper have qualitatively different effects on cognitive function in T1DM that depend in part on the timing of exposure during development, independent of onset age. This information extends the known benefits of avoiding both Hypo and chronic Hyper during childhood to include preservation of specific cognitive skills.

Cognition and brain imaging in type 1 diabetes

Type 1 diabetes has mild effects on cognition that are influenced by age of onset, hyperglycemia, and hypoglycemic episodes. Some of these changes occur quite early in the disease course. Studies using relatively new brain imaging techniques have also shown brain changes in adults and children that appear to be influenced by metabolic abnormalities present in diabetes. Early detections of brain changes may be early indicators of subsequent cognitive abnormalities.

Cognitive function in children and subsequent type 2 diabetes

OBJECTIVE

To assess whether a diagnosis of type 2 diabetes by age 42 years is associated with prior cognitive deficits in childhood.

RESEARCH DESIGN AND METHODS

Logistic regression estimated type 2 diabetes risk among 9,113 members of the 1958 British birth cohort of the National Child Development Study (NCDS). Associations with type 2 diabetes were estimated for general ability and reading comprehension assessments at age 11 years, modeled using SD units. Adjustment was for markers of early-life exposures, social and material family characteristics, sex, and disability, with further adjustment for BMI at age 7 years.

RESULTS

Adjusted odds ratios (95% CIs) for type 2 diabetes (n = 69) are 0.67 (0.51-0.87) for general ability and 0.58 (0.44-0.77) for reading comprehension. Neither additional adjustment for BMI, nor limiting the definition of type 2 diabetes to onset after age 33 years altered the associations substantially.

CONCLUSIONS

Impaired cognitive function may precede clinical onset of type 2 diabetes.

Regional brain volume differences associated with hyperglycemia and severe hypoglycemia in youth with type 1 diabetes

OBJECTIVE

Despite interest in the effects of type 1 diabetes on the developing brain, structural brain volumes in youth with this disease have not previously been examined. This study is the first to quantify regional brain volume differences in a large sample of youth with diabetes.

RESEARCH DESIGN AND METHODS

Magnetic resonance images (MRIs) were acquired from youth with diabetes (n = 108) and healthy sibling control subjects (n = 51) aged 7-17 years. History of severe hypoglycemia was assessed by parent interview and included seizure, loss of consciousness, or requiring assistance to treat. A1C values since diagnosis were obtained from medical records; median A1C was weighted by duration of disease. Voxel-based morphometry was used to determine the relationships of prior hypo- and hyperglycemia to regional grey and white matter volumes across the whole brain.

RESULTS

No significant differences were found between diabetic and healthy control groups in grey or white matter. However, within the diabetic group, a history of severe hypoglycemia was associated with smaller grey matter volume in the left superior temporal region. Greater exposure to hyperglycemia was associated with smaller grey matter volume in the right cuneus and precuneus, smaller white matter volume in a right posterior parietal region, and larger grey matter volume in a right prefrontal region.

CONCLUSIONS

Qualitatively different relationships were found between hypo- and hyperglycemia and regional brain volumes in youth with type 1 diabetes. Future studies should investigate whether these differences relate to cognitive function and how these regions are affected by further exposure.

Predictors of cognitive impairment in type 1 diabetes

A decline in cognitive function has been reported in type 1 diabetes, but its relation to different disease factors such as hypoglycemic events and peripheral neuropathy is controversial. The objective of the present study was to identify factors that are important for cognitive impairment in type 1 diabetes. A cross-sectional study was performed in adult patients (N=150) with type 1 diabetes (duration 26.6+/-11.4 years). Function in different cognitive domains was evaluated by the same trained examiner, in order to eliminate inter-rater variability. Peripheral nerve function was tested quantitatively. Predictors of cognitive impairment were identified using multiple regression analysis. The major finding was that long diabetes duration and young age of diabetes onset were the strongest predictors of low scores in psychomotor speed, memory, processing speed, attention, working memory, verbal ability, general intelligence, executive functions and a low global score. The number of previous hypoglycemic events had no defined effect upon cognitive functioning. Other significant predictors were low compound muscle action potential (CMAP) (for visual perception-organization), old age (for visual-spatial ability), short stature, high BMI and hypertension. Presence of retinopathy and long-term metabolic control correlated with nerve conduction defects, but not with cognitive impairment. Although a history of hypoglycemic events was not a predictor of cognitive impairment, we cannot exclude the possibility that the influence of young age of diabetes onset depends on the effect of hypoglycemic events early in life. The clinical relationships of cognitive impairment differ from those of peripheral neuropathy, indicating a different pathogenesis. The influence of diabetes duration, BMI, height, age and CMAP may suggest that loss of the neuroprotective effects of insulin or insulin-like growth factors plays a role.

Subtractive hybridisation screen identifies genes regulated by glucose deprivation in human neuroblastoma cells

Glucose is the major source of energy for the brain and inadequate glucose supply causes damage of neuronal cells. In this study we employed the human neuroblastoma cell line SH-SY5Y, as an in vitro model for neuronal cells, to identify genes regulated by glucose deprivation. Using subtractive hybridisation screen, validated by Northern analysis, we identify for the first time specific targets of the glucopenic response. These genes are involved in key cellular process including gene transcription, protein synthesis, mitochondrial metabolism, neuronal development, neuroprotection and neuronal apoptosis. Our findings suggest that the fate of neuronal cells undergoing glucose starvation relies on complex gene interactions. Modulation of the expression of these genes in vivo will enable determination of the precise role of each gene and possibly identify key elements and potential therapeutic targets of the glucopenic response.

Diabetes mellitus as a model of psychosomatic and somatopsychic interrelationships

The article reviews research on the problem of interrelationship between different physical and psychosocial factors in type 1 diabetes mellitus (DM1). The authors consider methodological principles of health-related quality of life (HRQoL) assessment in DM1 patients and stress the need for an integrated biopsychosocial approach to the management of the disease. DM1 is a chronic metabolic disease with an absolute requirement for insulin replacement therapy. The stress-inducing nature of DM1 is associated with its unexpected and dramatic manifestation in juvenile years, life-threatening nature of severe hypo-/hyperglycaemias and long-term complications, with the burden of diabetes self-management, threat of work disability, employment and career problems etc. These features of DM1 increase the likelihood of the development of anxiety and depressive disorders, which, in turn, may negatively influence the course of diabetes and in particular, diabetes self-care. This necessitates early diagnosis of emotional and behavioral disturbances in DM1 using self-report instruments as well as clinical assessment. Evidence suggests that active problem-focused coping behavior and adequate social support promote adherence to diabetes regimes and may act as a buffer against negative effects of the disease on HRQoL in DM1 patients. The core element in the HRQoL structure is personal disease picture (as opposed by objective clinical picture)--the cognitive-affective-behavioral complex reflecting the patient's personal perception of the disease. Examination of the personal disease picture and attitude towards the ailment in DM1 patients may help to improve understanding of the mechanisms of poor adjustment. Problems in disease adjustment can be detected also by diabetes-specific HRQoL assessment. The measures of HRQoL can be applied as screening instruments useful in increasing the effectiveness of patient-provider interactions and diabetes care.

Hypoglycemia: a complication of diabetes therapy in children

The experience of hypoglycemia is probably the most feared and hated consequence of life with type 1 diabetes among pediatric patients and their parents. Although transient detrimental effects are clearly disturbing and may have severe results, there is surprisingly little evidence of long-term CNS damage, even after multiple hypoglycemic episodes, except in rare instances. Despite the latter evidence, we advocate that every treatment regimen be designed to prevent hypoglycemia without inducing unacceptable hyperglycemia and increasing the risk of micro- and macrovascular complications.

Cognitive functioning in children with early onset type 1 diabetes and severe hypoglycemia

OBJECTIVE

To investigate whether severe hypoglycemia in young children with early-onset type 1 diabetes (T1DM) is associated with subsequent abnormalities in cognitive status.

STUDY DESIGN

Recruitment was from a large population-based database of children and adolescents with T1DM. Children and adolescents with early-onset T1DM (<6 years) were eligible for the study. Diabetic individuals (n = 41) with a prospectively documented history of seizure or coma were compared with peers with no history of severe hypoglycemic events (n = 43). A comprehensive test battery of learning and memory was used together with intellectual and behavioral measures.

RESULTS

No significant group differences were revealed on the intellectual, memory, or behavioral measures. Similarly, those participants with a history of early first seizure did not differ from their peers with no seizures. There were no significant group differences on the memory subtests that were examined given their potential sensitivity to compromised hippocampal function.

CONCLUSIONS

There was no clear evidence from this cohort that episodes of seizure or coma, even those occurring in very early childhood, resulted in broad cognitive dysfunction, nor was there evidence of specific memory difficulties at the time of testing in children and adolescents with early-onset T1DM.

Frequency and timing of severe hypoglycemia affects spatial memory in children with type 1 diabetes

OBJECTIVE

Repeated severe hypoglycemia has been reported to reduce long-term spatial memory in children with type 1 diabetes. Early exposure to hypoglycemia may be more damaging to cognitive function than later exposure. Our goal was to determine whether the age at which severe hypoglycemia occurs modulates the impact of severe hypoglycemia frequency on long-term spatial memory.

RESEARCH DESIGN AND METHODS

We combined data from three independent studies to obtain a sample of children aged 6-18 years with type 1 diabetes (n = 103) and nondiabetic control subjects (n = 60). Each study evaluated previous severe hypoglycemia and tested short (5 s)- and long (60 s)-delay spatial memory with the spatial delayed response task. Type 1 diabetic participants were categorized as having zero, one to two, or three or more severe hypoglycemic episodes and as having their first severe hypoglycemic episode before or after 5 years of age. Information on chronic hyperglycemia (HbA1c values) was also collected.

RESULTS

We found that repeated severe hypoglycemia (more than three episodes) reduced long-delay spatial delayed response performance, particularly when severe hypoglycemic episodes began before the age of 5 years. Age of type 1 diabetes onset and estimates of chronic hyperglycemia did not influence performance.

CONCLUSIONS

High frequency of and early exposure to severe hypoglycemia during development negatively affects spatial long-term memory performance.

Influence of an early-onset age of type 1 diabetes on cerebral structure and cognitive function

OBJECTIVE

Children who develop type 1 diabetes before age 7 years (early-onset diabetes; EOD) have comparatively poorer cognitive abilities. Whether this relates to psychosocial consequences of chronic illness or organic factors related to diabetes and its complications remains unresolved. We hypothesized that if differences in neuroradiological structure and cognitive ability coexisted in those who had EOD, then an organic component to their etiology was likely.

RESEARCH DESIGN AND METHODS

A cohort of 71 young adults with long-duration type 1 diabetes diagnosed during childhood or adolescence participated in a cross-sectional evaluation of cognitive ability (neuropsychological test battery) and brain structure (magnetic resonance imaging). Diabetes onset age, preceding severe hypoglycemia exposure, retinopathy status, and diabetes duration were examined as potential correlates of cognitive and neuroradiological differences. No participants had previous neuropsychological pathology.

RESULTS

In EOD participants (n = 26), current intellectual ability (Wechsler Adult Intelligence Scale-Revised performance IQ; P = 0.03) and information processing ability (Choice Reaction Time; P = 0.006) were comparatively poorer than was observed in those with later- onset diabetes (n = 45). Furthermore, lateral ventricular volumes were 37% greater (P = 0.002) and ventricular atrophy was more prevalent (61 vs. 20%; P = 0.01) in the EOD group than in those who had later-onset type 1 diabetes.

CONCLUSIONS

An early childhood onset of type 1 diabetes was associated with mild central brain atrophy and significant differences in intellectual performance in adulthood, implying that neurodevelopment may be adversely affected by EOD. The differences observed in brain structure support an organic contribution to their etiology but do not exclude a coexistent contribution of psychosocial factors.

Childhood precursors of adolescent outcomes in type 1 diabetes mellitus

Contemporary outcome measures of chronic illnesses such as type 1 diabetes mellitus are broader than those clinical outcomes traditionally assessed in therapeutic encounters. A holistic approach emphasises quality of life and emotional well-being as well as the achievement of optimal disease management. This paper reviews current knowledge about growth, metabolic control, diabetes complications, neurocognitive and psychological outcomes as well as health-related quality of life in childhood diabetes mellitus. It is suggested that the antecedents of adverse diabetes and psychological outcomes in adolescence lie in the years prior to adolescence. The model of care in childhood diabetes mellitus must be focussed on earlier screening and intervention if adverse outcomes are to be reduced.

Psychiatric morbidity and health outcome in Type 1 diabetes--perspectives from a prospective longitudinal study

AIMS

To describe psychiatric status and relationship to metabolic control in adolescents with Type 1 diabetes studied prospectively from diagnosis.

METHODS

Adolescents (n = 41) completed a self-report measure of psychiatric status 10 years after disease onset. Metabolic control information was recorded prospectively from diagnosis. The rate and type of psychiatric disorder were determined and the relationship between mental health status and metabolic control history examined.

RESULTS

Thirty-seven per cent of the adolescents met criteria for a DSM-IV psychiatric disorder, two to three times higher than community levels of psychiatric morbidity. Females were significantly more likely to receive a diagnoses (chi2 = 4.98, P < 0.05). Two thirds of participants had experienced at least one serious hypoglycaemic episode and one third had a history of chronic poor metabolic control. DSM-IV diagnoses were present in half of those with a history of chronic poor control, one third of the hypoglycaemia group and one quarter of well controlled participants. Adolescents with a current Mood (t = -2.83, P < 0. 01), Anxiety (t = -3.77, P = 0.001) or Behaviour (t = 2.56, P < 0.05) disorder and those with a history of poorly controlled diabetes (F (2,29) = 5.4, P = 0.01) had higher externalizing behaviour problem scores at diagnosis than those without current disorder.

CONCLUSIONS

Adolescents with Type 1 diabetes are at high risk for psychiatric disorder. Poorly controlled diabetes over the first 10 years of illness was associated with pre-existing behaviour problems at diagnosis and there was a trend for an association with current psychiatric status.

A prospective study of severe hypoglycemia and long-term spatial memory in children with type 1 diabetes

In a previous retrospective study, severe hypoglycemia (SH) was associated with decreased long-term spatial memory in children with type 1 diabetes mellitus (T1DM). In this study, we tested the hypothesis that prospectively ascertained SH would also be associated with decreased spatial long-term memory over time. Children with T1DM (n = 42) and sibling controls (n = 25) performed a spatial delayed response (SDR) task with short and long delays and other neuropsychological tests at baseline and after 15 months of monitoring. Extreme glycemic events and other medical complications were recorded prospectively during follow-up. Fourteen T1DM children experienced at least one episode of SH during the follow-up period (range = 1-5). After controlling for long-delay SDR performance at baseline, age, gender, and age of onset, the presence of SH during the prospective period was statistically associated with decreased long-delay SDR performance at follow-up (semipartial r = -0.38, p = 0.017). This relationship was not seen with short-delay SDR or with verbal or object memory, attention, or motor speed. These results, together with previously reported data, support the hypothesis that SH has specific, negative effects on spatial memory skills in T1DM children.

Health-related quality of life and metabolic control in children with type 1 diabetes: a prospective cohort study

OBJECTIVE

To assess change in health-related quality of life (HRQOL) in children with diabetes over 2 years and determine its relationship to change in metabolic control.

RESEARCH DESIGN AND METHODS

In 1998, parents of children aged 5-18 years attending a tertiary diabetes clinic reported their child's HRQOL using the Child Health Questionnaire PF-50. Those aged 12-18 years also self-reported their HRQOL using the analogous Child Health Questionnaire CF-80. HbA(1c) levels were recorded. In 2000, identical measures were collected for those who were aged < or =18 years and still attending the clinic.

RESULTS

Of 117 eligible subjects, 83 (71%) participated. Parents reported no significant difference in children's HRQOL at baseline and follow-up. However, adolescents reported significant improvements on the Family Activities (P < 0.001), Bodily Pain (P = 0.04), and General Health Perceptions (P = 0.001) scales and worsening on the Behavior (P = 0.04) scale. HbA(1c) at baseline and follow-up were strongly correlated (r = 0.57). HbA(1c) increased significantly (mean 7.8% in 1998 vs. 8.5% in 2000; P < 0.001), with lower baseline HbA(1c) strongly predicting an increase in HbA(1c) over the 2 years (r(2) = 0.25, P < 0.001). Lower parent-reported Physical Summary and adolescent-reported Physical Functioning scores at baseline also predicted increasing HbA(1c). Poorer parent-reported Psychosocial Summary scores were related to higher HbA(1c) at both times but did not predict change in HbA(1c).

CONCLUSIONS

Changes in parent and adolescent reports of HRQOL differ. Better physical functioning may protect against deteriorating HbA(1c), at least in the medium term. While the HRQOL of children with diabetes does not appear to deteriorate over time, we should not be complacent, as it is consistently poorer than that of their healthy peers.

Insulin lispro: a potential role in preventing nocturnal hypoglycaemia in young children with diabetes mellitus

AIMS

The long duration of action of soluble insulin given in the evening could contribute to the high prevalence of nocturnal hypoglycaemia seen in young children with Type 1 diabetes mellitus (T1DM). We examined whether replacing soluble insulin with insulin lispro reduced this risk in children on a three times daily insulin regimen.

METHODS

Open crossover study comparing insulin lispro vs. soluble insulin in 23 (16 boys) prepubertal children (age 7-11 years) with T1DM on three injections/day; long-acting isophane insulin remained identical. At the end of each 4-month treatment arm, an overnight 15-min venous sampled blood glucose profile was performed.

RESULTS

Despite similar blood glucose levels pre-evening meal (lispro vs. soluble: mean +/- se 6.5 +/- 1.0 vs. 7.1 +/- 1.1 mmol/l, P = 0.5), post-meal (18.00-22.00 h) blood glucose levels were lower on insulin lispro (area under curve 138 +/- 12 vs. 170 +/- 13 mmol min-1 l-1, P = 0.03). In contrast, in the early night (22.00-04.00 h) the prevalence of low blood glucose levels (< 3.5 mmol/l) was lower on lispro (8% of blood glucose levels) than on soluble insulin (13%, P = 0.01). In the early morning (04.00-07.00 h) mean blood glucose and prevalence of low levels were no different between the two treatment groups, and fasting (07.00 h) blood glucose levels were similar (6.1 +/- 0.8 vs. 6.3 +/- 0.9 mmol/l, P = 0.8). At the end of each treatment arm there were no differences in HbA1c (lispro vs. soluble 8.6% vs. 8.4%, P = 0.3), or in insulin doses (mean, range 0.97, 0.68-1.26 vs. 0.96, 0.53-1.22 U/kg per day, P = 0.2).

CONCLUSIONS

The shorter duration of action of insulin lispro given before the evening meal may reduce the prevalence of early nocturnal hypoglycaemia without compromising HbA1c in young children with T1DM.

Neurocognitive functioning in children with type-1 diabetes with and without episodes of severe hypoglycaemia

Previous studies have shown that recurrent severe hypoglycaemia can cause long-term cognitive impairment in children with type-1 diabetes, but the results are controversial, possibly due to the heterogeneity of samples and lack of comprehensive neuropsychological assessments of children. The aim of this study was to assess the effects of diabetes and severe hypoglycaemia on the neurocognitive functioning of children with a standardized, wide age-range neuropsychological test battery designed for the assessment of children. Eleven children with diabetes and a history of severe hypoglycaemia, 10 children with diabetes without a history of severe hypoglycaemia, and 10 healthy control children (a total of 31 children: 14 males and 17 females, age range 5 years 6 months to 11 years 11 months, mean 9 years 4 months, SD 1 year 11 months) were studied using the Wechsler Intelligence Scale for Children-Revised (WISC-R) and the NEPSY, a Developmental Neuropsychological Assessment. The NEPSY assessed development in attention and executive functions, language, sensorimotor functions, visuospatial processing, and learning and memory. Children with a history of severe hypoglycaemia had more neuropsychological impairments, more learning difficulties (as reported by parents), and needed more part-time special education than those in the other groups. Significant differences were found in verbal short-term memory and phonological processing. Results suggest that severe hypoglycaemia is a risk factor for learning due to deficits in auditory-verbal functioning.