Elisabeth Northam

Development of Executive Functions Through Late Childhood and Adolescence in an Australian Sample

Although there have been significant theoretical advances in the field of child neuropsychology, developmental features of adolescence have received less attention. Progress in clinical practice is restricted due to a lack of well-standardized, developmentally appropriate assessment techniques. This article addresses these issues in relation to executive skills. These abilities are targeted for 2 reasons: first, because they are often considered to be mature during late childhood and adolescence, despite limited investigation in this age range; and second, because of their central importance to efficient day-to-day functioning. Using a normative sample of 138 children, aged 11.0 to 17.11 years, this article plots the development of executive skills through late childhood and early adolescence and interprets progress in these skills with reference to current neurological and cognitive theory.

Relationships between cognitive and behavioral measures of executive function in children with brain disease.

This study addressed the clinical and construct validity of the Behavior Rating Inventory of Executive Function. (BRIEF: Gioia, Isquith, Guy, & Kenworthy, 2000), a questionnaire designed to tap behavioral aspects of executive functions in children. BRIEF profiles in early treated phenylketonuria (PKU; n = 44), early treated hydrocephalus (n = 45), frontal focal lesions (n = 20) and controls (n = 80) were examined. Clinical validity was supported through significant between-group comparisons, especially between the frontal focal lesion group and other groups. To examine construct validity, raw scores on cognitive executive function measures including the Contingency Naming Test (CNT), Rey Complex Figure (RCF), Tower of London (TOL), and Controlled Oral Word Association Test (COWAT), were correlated with BRIEF scale scores. Few significant correlations were found, indicating cognitive and behavioral measures appear to tap different constructs within the executive function domain. A dissociation was found between behavioral and cognitive impairments in the frontal as opposed to PKU and hydrocephalus groups. This is discussed in relation to underlying pathology, the cognitive measures used, and possible limitations in the BRIEFs usefulness for measuring behavioral executive dysfunction in groups only mildly affected by neurological compromise.

Central Nervous System Function in Youth With Type 1 Diabetes 12 Years After Disease Onset

OBJECTIVE—In this study, we used neurocognitive assessment and neuroimaging to examine brain function in youth with type 1 diabetes studied prospectively from diagnosis. RESEARCH DESIGN AND METHODS—We studied type 1 diabetic (n = 106) and control subjects (n = 75) with no significant group difference on IQ at baseline 12 years previously by using the Wechsler Abbreviated Scale of General Intelligence, magnetic resonance spectroscopy and imaging, and metabolic control data from diagnosis. RESULTS—Type 1 diabetic subjects had lower verbal and full scale IQs than control subjects (both P < 0.05). Type 1 diabetic subjects had lower N-acetylaspartate in frontal lobes and basal ganglia and higher myoinositol and choline in frontal and temporal lobes and basal ganglia than control subjects (all P < 0.05). Type 1 diabetic subjects, relative to control subjects, had decreased gray matter in bilateral thalami and right parahippocampal gyrus and insular cortex. White matter was decreased in bilateral parahippocampi, left temporal lobe, and middle frontal area (all P < 0.0005 uncorrected). T2 in type 1 diabetic subjects was increased in left superior temporal gyrus and decreased in bilateral lentiform nuclei, caudate nuclei and thalami, and right insular area (all P < 0.0005 uncorrected). Early-onset disease predicted lower performance IQ, and hypoglycemia was associated with lower verbal IQ and volume reduction in thalamus; poor metabolic control predicted elevated myoinositol and decreased T2 in thalamus; and older age predicted volume loss and T2 change in basal ganglia. CONCLUSIONS—This study documents brain effects 12 years after diagnosis in a type 1 diabetic sample whose IQ at diagnosis matched that of control subjects. Findings suggest several neuropathological processes including gliosis, demyelination, and altered osmolarity.

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.

Neuropsychological Complications of IDDM in Children 2 Years After Disease Onset

OBJECTIVE To compare the neuropsychological profiles of children with IDDM with a community control group at two time points: 3 months after disease onset and 2 years after the baseline assessment. RESEARCH DESIGN AND METHODS A total of 123 children (age 3–14 years) with recent IDDM onset were compared with 129 community control subjects, stratified for age and sex, on standardized measures of general intelligence, attention, speed of processing, memory, learning, executive skills, and behavioral adjustment soon after diagnosis and 2 years later. Exclusion criteria were premorbid evidence of central nervous system disease or trauma, or English not spoken in the home. RESULTS There were no differences between children with IDDM and control subjects on any measure at the initial assessment 3 months after disease onset. Two years later, children with IDDM tended to show a less positive change, relative to control subjects, in their standardized scores on measures of general intelligence, and significantly so on the vocabulary (P < 0.01) and block design (P < 0.05) subtests. Multivariate group differences were also apparent on speed of processing (P < 0.05) and learning (P < 0.01) subtests, reflecting smaller developmental gains in the children with IDDM when compared with control subjects. CONCLUSIONS The findings are consistent with previous reports, suggesting that IDDM is associated with an increased risk of mild neuropsychological dysfunction. The skills most affected in this cohort were information processing speed, acquisition of new knowledge, and conceptual reasoning abilities. Clinicians and educators should be made aware of the risk of specific neuropsychological deficits in children with IDDM.

Routine Psychological Screening in Youth With Type 1 Diabetes and Their Parents: A notion whose time has come?

In the post-DCCT (Diabetes Control and Complications Trial) (1) and -EDIC (Epidemiology of Diabetes Interventions and Complications) (2) eras, considerable effort has been expended on early detection and treatment of diabetes-related microvascular complications in youth using screening programs. Numerous consensus statements have been generated relating to the timing, frequency, and content of such programs (3–7). Although each recommends a slightly different approach to screening, the same basic principles apply—achieve and maintain excellent glycemic control; reduce known and modifiable risk factors, such as smoking, obesity, hyperlipidemia, and hypertension; and screen for nephropathy and retinopathy on a regular basis following the inset of puberty. To be considered successful, any screening program must satisfy several criteria (8): Certainly, given what we know about microvascular complications and their progression and treatment, universal diabetes complication screening programs satisfy most of these prerequisites. Ten years after the DCCT, average levels of metabolic control have improved in most clinical reports of children and adolescents with type 1 diabetes, although population-based data remain scanty and perhaps less optimistic (9–14). Contemporary clinic-based reports of microvascular complication rates in adolescence have shown a concomitant improvement (15–18). On the other hand, reports relating to health-related quality of life (HRQOL) and psychological outcomes have been distressingly suboptimal (19–24). Although not all studies report significant associations (25–27), there are a number of reports showing that psychosocial dysfunction and family conflict are close correlates of poor health …

Therapy Insight: the impact of type 1 diabetes on brain development and function

The CNS is one of the main organ systems that is affected in type 1 diabetes, as both cerebral glucose and insulin levels are frequently abnormal, even when the diabetes is well-controlled. Literature is emerging that documents pathophysiological CNS changes and neurocognitive deficits in both adults and children with type 1 diabetes, but empirical findings to date have often been inconsistent and difficult to interpret. This article provides a comprehensive review of current knowledge about the impact of type 1 diabetes on brain development and function, focusing particularly on the evidence for specific illness-related risk factors for CNS sequelae. We argue that clinical management of young patients with type 1 diabetes should take into account current knowledge of the relative risks of hypoglycemia and hyperglycemia to the developing brain.

Neuropsychological profiles of young people with type 1 diabetes 12 yr after disease onset

Lin A, Northam EA, Rankins D, Werther GA, Cameron FJ. Neuropsychological profiles of young people with type 1 diabetes 12 yr after disease onset.

Interventions to promote optimal health outcomes in children with Type 1 diabetes—are they effective?

The incidence of Type 1 diabetes is increasing worldwide, imposing enormous public health costs, as well as profoundly affecting individual quality of life. There is evidence that psychological problems are increased in children with diabetes and this morbidity is often associated with poor metabolic control. Specific risk factors for this dual morbidity are emerging from empirical studies. The next challenge is to identify effective interventions for use with children at risk for adverse mental and physical health outcomes. The intervention literature is reviewed. It is noted that most studies have used diabetes‐specific, unstandardized interventions in groups of adolescents, with few interventions trialled with younger children. No study has targeted a specific psychological disorder such as behaviour problems or depression, both of which are known to be increased in children with diabetes and for which effective standardized interventions are available. Attention is drawn to methodological limitations in many of the studies conducted to date and suggestions made to reduce these in future interventions attempting to reduce the burden of illness in children with diabetes.

Psychosocial well-being and functional outcomes in youth with type 1 diabetes 12 years after disease onset

OBJECTIVE Type 1 diabetes in youth and community controls were compared on functional outcomes. Relationships were examined between psychosocial variables at diagnosis and functional outcome 12 years later. RESEARCH DESIGN AND METHODS Participants were subjects with type 1 diabetes (n = 110, mean age 20.7 years, SD 4.3) and control subjects (n = 76, mean age 20.8 years, SD 4.0). The measures used included the Youth Self-Report and Young Adult Self-Report and a semi-structured interview of functional outcomes. Type 1 diabetes participants also provided information about current diabetes care and metabolic control from diagnosis. RESULTS Type 1 diabetes participants and control subjects reported similar levels of current well-being but for the youth with type 1 diabetes, the mental health referral rates over the previous 12 years were higher by 19% and school completion rates were lower by 17%. Over one-third of clinical participants were not currently receiving specialist care and this group had higher mental health service usage in the past (61 vs. 33%) and lower current psychosocial well- being. Within the type 1 diabetes group, behavior problems, high activity, and low family cohesion at diagnosis predicted lower current well-being, but were not associated with metabolic control history. Poorer metabolic control was associated with higher mental health service usage. CONCLUSIONS Type 1 diabetes participants report similar levels of current psychosocial well-being compared with control subjects, but higher levels of psychiatric morbidity since diagnosis and lower school completion rates. Psychiatric morbidity was associated with poor metabolic control and failure to transition to tertiary adult diabetes care.