Age-related loss of brain volume and T2 relaxation time in youth with Type 1 diabetes

OBJECTIVE: Childhood-onset type 1 diabetes is associated with neurocognitive deficits, but there is limited evidence to date regarding associated neuroanatomical brain changes and their relationship to illness variables such as age at disease onset. This report examines age-related changes in volume and T2 relaxation time (a fundamental parameter of magnetic resonance imaging that reflects tissue health) across the whole brain. RESEARCH DESIGN AND METHODS: Type 1 diabetes, N = 79 (mean age 20.32 ± 4.24 years), and healthy control participants, N = 50 (mean age 20.53 ± 3.60 years). There were no substantial group differences on socioeconomic status, sex ratio, or intelligence quotient. RESULTS: Regression analyses revealed a negative correlation between age and brain changes, with decreasing gray matter volume and T2 relaxation time with age in multiple brain regions in the type 1 diabetes group. In comparison, the age-related decline in the control group was small. Examination of the interaction of group and age confirmed a group difference (type 1 diabetes vs. control) in the relationship between age and brain volume/T2 relaxation time. CONCLUSIONS: We demonstrated an interaction between age and group in predicting brain volumes and T2 relaxation time such that there was a decline in these outcomes in type 1 diabetic participants that was much less evident in control subjects. Findings suggest the neurodevelopmental pathways of youth with type 1 diabetes have diverged from those of their healthy peers by late adolescence and early adulthood but the explanation for this phenomenon remains to be clarified

Pharmaceutical opioid analgesic and heroin dependence: How do treatment-seeking clients differ in Australia?

Introduction and Aims. Non-prescribed use of pharmaceutical opioid analgesics (POA) has been escalating internationally. In Australia, few studies have examined if POA users have similar characteristics and treatment needs to heroin users. The aim of this study was to compare those presenting for treatment where heroin versus POA were the primary drugs of concern. Design and Methods. A convenience sample of 192 treatment entrants were recruited from alcohol and drug treatment services in four Australian jurisdictions. A structured interview collected data on demographic characteristics, substance use, self-perceived mental and physical health, crime and harms resulting from drug use. Multivariate analyses were performed to identify characteristics which may differentiate those seeking treatment for heroin compared with POA. Results. Most treatment entrants sampled reported a history of injection drug use and use of both heroin and POA. However, those with primary POA problems were less likely to report an overdose history (adjusted odds ratio 0.90, 95% confidence interval 0.81–0.99) and more likely to initiate opioid use for pain (adjusted odds ratio 2.52, 95% confidence interval 1.04–6.12) than those with primary heroin problems. Latent Class Analysis found that, while most of the POA group were similar to heroin users in demographics, health and injecting drug use, there was a small, distinct group of primary POA problem users that did not typically inject and who commonly initiated opioid use for pain and also experienced elevated physical and mental health disability.Discussion and Conclusions. While some differences existed, this study of Australian treatment seekers found many similar characteristics between those with primary problems with heroin and POA. Few non-injecting POA were recruited in this sample. This finding contrasts with reports of a growing population of opioid-dependent people with characteristics that are distinct from traditional opioid-dependent populations, which may reflect the orientation of current treatment systems in Australia towards injection drug users.[Nielsen S, Bruno R, Lintzeris N, Fischer J, Carruthers S, Stoové M. Pharmaceutical opioid analgesic and heroin dependence: How do treatment-seeking clients differ in Australia? Drug Alcohol Rev 2011;30:291–299

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