Cognition in patients with post-bariatric hypoglycemia.

Objective: Bariatric surgery, a highly effective treatment for obesity and associated comorbidities, may improve cognition and brain volume in parallel with cardiometabolic function. However, some post-bariatric individuals develop post-bariatric hypoglycemia (PBH), which can be frequent and severe. The impact of recurrent hypoglycemia on cognition in PBH is unknown.

Hyperglycemia and hyperinsulinemia effects on anterior cingulate cortex myoinositol-relation to brain network functional connectivity in healthy adults.

Brain mechanisms underlying the association of diabetes metabolic disorders-hyperglycemia and insulin resistance-with cognitive impairment are unknown. Myoinositol is a brain metabolite involved in cell osmotic balance, membrane phospholipid turnover, and second messenger neurotransmission, which affect brain function. Increased brain myoinositol and altered functional connectivity have been found in diabetes, mild cognitive impairment, and Alzheimer's disease, but the independent effects of plasma glucose and insulin on brain myoinositol and function are not characterized.

Association of Cognitive Function and Retinal Neural and Vascular Structure in Type 1 Diabetes.

Context: Cognitive dysfunction is a growing and understudied public health issue in the aging type 1 diabetic population and is difficult and time-consuming to diagnose. Studies in long duration type 1 diabetes have reported the presence of proliferative diabetic retinopathy was associated with cognitive dysfunction.

Objective: This study assessed whether structural and vascular abnormalities of the retina, representing an extension of the central nervous system, are associated with cognitive impairment and other complications of type 1 diabetes.

Acute Hyperglycemia Increases Brain Pregenual Anterior Cingulate Cortex Glutamate Concentrations in Type 1 Diabetes.

The brain mechanisms underlying the association of hyperglycemia with depressive symptoms are unknown. We hypothesized that disrupted glutamate metabolism in pregenual anterior cingulate cortex (ACC) in type 1 diabetes (T1D) without depression affects emotional processing. Using proton MRS, we measured glutamate concentrations in ACC and occipital lobe cortex (OCC) in 13 subjects with T1D without major depression (HbA 7.

Cognitive Function Deficits Associated With Long-Duration Type 1 Diabetes and Vascular Complications.

Objective: Patients with type 1 diabetes now live long enough to experience cognitive decline. During middle age, they show mild cognitive deficits, but it is unknown whether severity increases with aging or whether cognitive profiles are similar to those of age-matched peers with and without diabetes.

Research Design And Methods: We tested and compared cognition in 82 individuals with 50 or more years of type 1 diabetes (Medalists), 31 age-matched individuals with type 2 diabetes, and 30 age-matched control subjects without diabetes.

Prefronto-temporal white matter microstructural alterations 20 years after the diagnosis of type 1 diabetes mellitus.

Objective: Microvascular pathophysiology that uniquely manifests as white matter (WM) abnormalities is often implicated in type 1 diabetes mellitus (T1DM)-related central nervous system (CNS) complications. This study sought to identify regional WM abnormalities in young adults diagnosed with T1DM and further examine their association with cognitive and emotional dysfunction.

Research Design And Methods: Diffusion tensor images (DTI) obtained from 34 young adults with T1DM for ≥15 years (mean duration, 20.

Functional Connectivity of Insula, Basal Ganglia, and Prefrontal Executive Control Networks during Hypoglycemia in Type 1 Diabetes.

Unlabelled: Human brain networks mediating interoceptive, behavioral, and cognitive aspects of glycemic control are not well studied. Using group independent component analysis with dual-regression approach of functional magnetic resonance imaging data, we examined the functional connectivity changes of large-scale resting state networks during sequential euglycemic-hypoglycemic clamp studies in patients with type 1 diabetes and nondiabetic controls and how these changes during hypoglycemia were related to symptoms of hypoglycemia awareness and to concurrent glycosylated hemoglobin (HbA1c) levels. During hypoglycemia, diabetic patients showed increased functional connectivity of the right anterior insula and the prefrontal cortex within the executive control network, which was associated with higher HbA1c.

Task-induced brain activity patterns in type 2 diabetes: a potential biomarker for cognitive decline.

Patients with type 2 diabetes demonstrate reduced functional connectivity within the resting state default mode network (DMN), which may signal heightened risk for cognitive decline. In other populations at risk for cognitive decline, additional magnetic resonance imaging abnormalities are evident during task performance, including impaired deactivation of the DMN and reduced activation of task-relevant regions. We investigated whether middle-aged type 2 diabetic patients show these brain activity patterns during encoding and recognition tasks.

Cerebral white matter integrity and resting-state functional connectivity in middle-aged patients with type 2 diabetes.

Early detection of brain abnormalities at the preclinical stage can be useful for developing preventive interventions to abate cognitive decline. We examined whether middle-aged type 2 diabetic patients show reduced white matter integrity in fiber tracts important for cognition and whether this abnormality is related to preestablished altered resting-state functional connectivity in the default mode network (DMN). Diabetic and nondiabetic participants underwent diffusion tensor imaging, functional magnetic resonance imaging, and cognitive assessment.

Network-level structural abnormalities of cerebral cortex in type 1 diabetes mellitus.

Type 1 diabetes mellitus (T1DM) usually begins in childhood and adolescence and causes lifelong damage to several major organs including the brain. Despite increasing evidence of T1DM-induced structural deficits in cortical regions implicated in higher cognitive and emotional functions, little is known whether and how the structural connectivity between these regions is altered in the T1DM brain. Using inter-regional covariance of cortical thickness measurements from high-resolution T1-weighted magnetic resonance data, we examined the topological organizations of cortical structural networks in 81 T1DM patients and 38 healthy subjects.

Prefrontal cortical deficits in type 1 diabetes mellitus: brain correlates of comorbid depression.

CONTEXT Neural substrates that may be responsible for the high prevalence of depression in type 1 diabetes mellitus (T1DM) have not yet been elucidated. OBJECTIVE To investigate neuroanatomic correlates of depression in T1DM. DESIGN Case-control study using high-resolution brain magnetic resonance images.

Resting-state brain functional connectivity is altered in type 2 diabetes.

Type 2 diabetes mellitus (T2DM) is a risk factor for Alzheimer disease (AD). Populations at risk for AD show altered brain activity in the default mode network (DMN) before cognitive dysfunction. We evaluated this brain pattern in T2DM patients.

Brain activation during working memory is altered in patients with type 1 diabetes during hypoglycemia.

Objective: To investigate the effects of acute hypoglycemia on working memory and brain function in patients with type 1 diabetes.

Research Design And Methods: Using blood oxygen level-dependent (BOLD) functional magnetic resonance imaging during euglycemic (5.0 mmol/L) and hypoglycemic (2.

Biomedical risk factors for decreased cognitive functioning in type 1 diabetes: an 18 year follow-up of the Diabetes Control and Complications Trial (DCCT) cohort.

Aims/hypothesis: In patients with type 1 diabetes, there has been concern about the effects of recurrent hypoglycaemia and chronic hyperglycaemia on cognitive function. Because other biomedical factors may also increase the risk of cognitive decline, this study examined whether macrovascular risk factors (hypertension, smoking, hypercholesterolaemia, obesity), sub-clinical macrovascular disease (carotid intima-media thickening, coronary calcification) and microvascular complications (retinopathy, nephropathy) were associated with decrements in cognitive function over an extended time period.

Methods: Type 1 diabetes patients (n = 1,144) who had completed a comprehensive cognitive test battery at entry into the Diabetes Control and Complications Trial were re-assessed at a mean of 18.

The associations of apolipoprotein E and angiotensin-converting enzyme polymorphisms and cognitive function in Type 1 diabetes based on an 18-year follow-up of the DCCT cohort.

Aims: Specific polymorphisms of the apolipoprotein E (APOE) and angiotensin-converting enzyme (ACE) genes appear to increase risk for Alzheimer's disease and cognitive dysfunction in the general population, yet little research has examined whether genetic factors influence risk of cognitive dysfunction in patients with Type 1 diabetes. The long-term follow-up of the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) population provides an opportunity to examine if specific genetic variations in APOE and ACE alter risk for cognitive decline.

Methods: Neurocognitive function in Type 1 diabetic subjects from the DCCT/EDIC study was assessed at DCCT entry and re-assessed approximately 18 years later, using a comprehensive cognitive test battery.

Altered prefrontal glutamate-glutamine-gamma-aminobutyric acid levels and relation to low cognitive performance and depressive symptoms in type 1 diabetes mellitus.

Context: Neural substrates for low cognitive performance and depression, common long-term central nervous system-related changes in patients with type 1 diabetes mellitus, have not yet been studied.

Objective: To investigate whether prefrontal glutamate levels are higher in patients with type 1 diabetes and whether an elevation is related to lower cognitive performance and depression.

Design: Cross-sectional study.

Impact of diabetes and its treatment on cognitive function among adolescents who participated in the Diabetes Control and Complications Trial.

Objective: The purpose of this study was to evaluate whether severe hypoglycemia or intensive therapy affects cognitive performance over time in a subgroup of patients who were aged 13-19 years at entry in the Diabetes Control and Complications Trial (DCCT).

Research Design And Methods: This was a longitudinal study involving 249 patients with type 1 diabetes who were between 13 and 19 years old when they were randomly assigned in the DCCT. Scores on a comprehensive battery of cognitive tests obtained during the Epidemiology of Diabetes Interventions and Complications follow-up study, approximately 18 years later, were compared with baseline performance.

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.

Regional brain activation during hypoglycemia in type 1 diabetes.

Context: Mechanisms underlying the brain response to hypoglycemia are not well understood.

Objective: Our objective was to determine the blood glucose level at which the hypothalamus and other brain regions are activated in response to hypoglycemia in type 1 diabetic patients and control subjects.

Design: This was a cross-sectional study evaluating brain activity using functional magnetic resonance imaging in conjunction with a hyperinsulinemic hypoglycemic clamp to lower glucose from euglycemia (90 mg/dl) to hypoglycemia (50 mg/dl).

The effects of type 1 diabetes on cerebral white matter.

Aim/hypothesis: Studies investigating the structure, neurophysiology and functional outcomes of white matter among type 1 diabetes patients have given conflicting results. Our aim was to investigate the relationship between type 1 diabetes and white matter hyperintensities.

Method: We assessed white matter integrity (using magnetic resonance imaging), depressive symptoms and neuropsychological function in 114 type 1 diabetes patients and 58 age-matched non-diabetic controls.

Long-term effect of diabetes and its treatment on cognitive function.

Background: Long-standing concern about the effects of type 1 diabetes on cognitive ability has increased with the use of therapies designed to bring glucose levels close to the nondiabetic range and the attendant increased risk of severe hypoglycemia.

Methods: A total of 1144 patients with type 1 diabetes enrolled in the Diabetes Control and Complications Trial (DCCT) and its follow-up Epidemiology of Diabetes Interventions and Complications (EDIC) study were examined on entry to the DCCT (at mean age 27 years) and a mean of 18 years later with the same comprehensive battery of cognitive tests. Glycated hemoglobin levels were measured and the frequency of severe hypoglycemic events leading to coma or seizures was recorded during the follow-up period.

Effects of type 1 diabetes on gray matter density as measured by voxel-based morphometry.

The effects of type 1 diabetes and key metabolic variables on brain structure are not well understood. Sensitive methods of assessing brain structure, such as voxel-based morphometry (VBM), have not previously been used to investigate central nervous system changes in a diabetic population. Using VBM, we compared type 1 diabetic patients aged 25-40 years with disease duration of 15-25 years and minimal diabetes complications with an age-matched, nondiabetic control group.

Attentional requirements for object-location priming.

The purpose of the present experiments was to investigate whether a verbal and a spatial secondary task would disrupt priming for object-location associations. Symbols were placed one at a time in one of nine locations in a rectangle. Implicit memory was tested with a reaction time (RT) task.