Emotional changes during experimentally induced hypoglycaemia in type 1 diabetes

Associations between Hunger and Psychological Outcomes: A Large-Scale Ecological Momentary Assessment Study

Studies assessing the association between hunger and psychological states have been conducted in laboratory settings, or limited to persons with eating disorders. In this study, 748 community-dwelling adults (56.4% women, 60.0 ± 9.3 years) completed the Ecological Momentary Assessment four times a day (08:00, 12:00, 16:00 and 20:00) for seven days. At each assessment, respondents indicated their current hunger level, food intake, and psychological states (sad, anxious, active, lively, distracted, anhedonic, angry, slow thinking and restless). Time-lagged associations assessing the effect of hunger on subsequent psychological states 4 h later and vice-versa were assessed. Hunger intensity increased subsequent active feeling (coefficient and 95% confidence interval: 0.029 (0.007; 0.051)) and lively feeling (0.019 (0.004; 0.034)) and decreased later slow thinking (-0.016 (-0.029; -0.003)). Previous eating increased later activity (0.116 (0.025; 0.208)). Feeling active (0.050 (0.036; 0.064)), lively (0.045 (0.023; 0.067)) and restless (0.040 (0.018; 0.063)) increased later hunger intensity, while distraction (-0.039 (-0.058; -0.019)) and slow thinking (-0.057 (-0.080; -0.034)) decreased it. No association was found between hunger, food intake and negative psychological states (sadness, anxiety and anger). Conclusions: Positive psychological states and hunger influence each other, while no association was found between hunger and negative psychological states.

Consistent Effects of Hypoglycemia on Cognitive Function in People With or Without Diabetes

OBJECTIVE

Hypoglycemia poses an immediate threat for cognitive function. Due to its association with acute cognitive impairment, the International Hypoglycemia Study Group (IHSG) defines a blood glucose level <3.0 mmol/L as "level 2 hypoglycemia." In the current study we investigated whether having diabetes, type of diabetes, or hypoglycemia awareness moderates this association.

RESEARCH DESIGN AND METHODS

Adults with type 1 diabetes with normal (n = 26) or impaired (n = 21) hypoglycemic awareness or with insulin-treated type 2 diabetes (n = 15) and age-matched control subjects without diabetes (n = 32) underwent a hyperinsulinemic-euglycemic-hypoglycemic glucose clamp (2.80 ± 0.13 mmol/L [50.2 ± 2.3 mg/dL]). At baseline and during hypoglycemia, calculation ability, attention, working memory and cognitive flexibility were measured with the Paced Auditory Serial Addition Test (PASAT) and the Test of Attentional Performance (TAP).

RESULTS

For the whole group, hypoglycemia decreased the mean ± SD proportion of correct answers on the PASAT by 8.4 ± 12.8%, increased reaction time on the TAP Alertness task by 32.1 ± 66.6 ms, and increased the sum of errors and omissions on the TAP Working Memory task by 2.0 ± 5.5 (all P < 0.001). Hypoglycemia-induced cognitive declines were largely irrespective of the presence or type of diabetes, level of symptomatic awareness, diabetes duration, or HbA1c.

CONCLUSIONS

IHSG level 2 hypoglycemia impairs cognitive function in people with and without diabetes, irrespective of type of diabetes or hypoglycemia awareness status. These findings support the cutoff value of hypoglycemia <3.0 mmol/L (<54 mg/dL) as being clinically relevant for most people with diabetes.

Real-Time Continuous Glucose Monitoring Can Predict Severe Hypoglycemia in People with Type 1 Diabetes: Combined Analysis of the HypoDE and DIAMOND Trials

Objective: We combined data from two landmark trials (DIAMOND and HypoDE) to examine the diagnostic performance of low glucose measurements derived from open and masked continuous glucose monitoring (CGM) to predict the occurrence of future severe hypoglycemia (SH). Methods: We analyzed hypoglycemia parameters (low blood glucose index [LBGI], % <70 mg/dL, 54-69 mg/dL [level 1 hypoglycemia] and <54 mg/dL [level 2 hypoglycemia]) from masked CGM over 14 days during baseline and from open CGM over 14 days after randomization. We used receiver operating characteristics (ROC) curves to evaluate the screening performance of these measures to predict future SH. Positive likelihood ratios were calculated to indicate the overall diagnostic performance of these parameters. Results: Data from 288 individuals with type 1 diabetes (mean age 45.6 ± 12.8 years, diabetes duration 20.7 ± 13.7 years, HbA1c 8.2% ± 1.0%, Hypoglycemia Unawareness Score 3.4 ± 2.1) were analyzed. Area under ROC-curve (AUC) for LBGI and % <70 mg/dL ranged between 0.68 and 0.75, indicating that LBGI and % <70 mg/dL could significantly predict future SH. Significance of AUC regarding % <54 mg/dL were mixed (0.63-0.72). Positive and negative likelihood ratios ranged between 1.82 to 3.40 and 0.56 to 0.32, respectively. Suggested optimal cutoff values were remarkedly lower in open CGM than in masked CGM. Conclusion: These results indicate that CGM-derived hypoglycemic parameters have a good screening performance to significantly predict future clinical hypoglycemia. In addition, this analysis suggests that cutoff values to indicate elevated hypoglycemia risk in the future are substantially lower in open CGM than in masked CGM. ClinicalTrials.gov registration numbers: HypoDE: NCT02671968. DIAMOND: NCT02282397.

The Relationship Between Emotional Intelligence and Diabetes Management: A Systematic Review

Diabetes has been associated with affective disorders which complicate the management of the disease. Emotional intelligence (EI), or the ability to perceive, facilitate, understand, and regulate emotions, has shown to be a protective factor of emotional disorders in general population. The main objective of this study was to systematically review the role of the EI construct in Type 1 and Type 2 diabetics and to observe how EI is related to biological and psychological variables. Comprehensive searches were conducted in PubMed, Scopus, PsycInfo, and Cochrane without time limitations, for studies examining the link between diabetes and EI. A total of 12 eligible studies were selected according to the inclusion criteria. We divided the results into four sections: (1) EI and hemoglobin glycosylated (HbA1c), (2) EI training effects, (3) differences in EI between persons with diabetes and without diabetes, and (4) EI and psychological adjustment and well-being. The results showed negative correlations between EI and HbA1c, positive effects of EI training on quality of life, anxiety, and glycemic control, no differences in EI between people with diabetes and healthy individuals, and, finally, negative correlations between EI and different psychological variables such as diabetes-related anxiety and distress, and positive correlations with quality of life, well-being, and marital satisfaction. This systematic review offers a starting point for a theoretical and practical understanding of the role played by EI in the management of diabetes and reveals that EI is a promising protective factor for biological and psychological variables in this population.

Effects of continuous glucose monitor-recorded nocturnal hypoglycaemia on quality of life and mood during daily life in type 1 diabetes

AIMS/HYPOTHESIS

The aim of this work was to assess the effect of spontaneous nocturnal hypoglycaemia on quality of life and mood during subsequent days in type 1 diabetes.

METHODS

A total of 153 people with type 1 diabetes participated in 6 days of blinded continuous glucose monitoring while documenting hypoglycaemic symptoms, quality of life and mood, daily. Hypoglycaemia was defined by interstitial glucose ≤3.9 mmol/l (IG_3.9) and ≤ 3.0 mmol/l (IG_3.0) for ≥15 min and was classified as asymptomatic if no hypoglycaemic symptoms were reported.

RESULTS

Self-estimated quality of life assessed by the EQ-5D VAS (but not by the WHO Well-Being Index) was higher the day after asymptomatic (but not after symptomatic) hypoglycaemic nights, as compared with non-hypoglycaemic nights (IG_3.9, p = 0.021; IG_3.0, p = 0.048). The effect increased with lower glucose nadir and longer duration of nocturnal hypoglycaemia (IG_3.9, p = 0.03). The finding was confined to participants with impaired hypoglycaemia awareness. There was no effect of nocturnal hypoglycaemia on mood or self-estimated effectiveness at work the following day.

CONCLUSIONS/INTERPRETATION

Individuals with type 1 diabetes and impaired hypoglycaemia awareness reported higher quality of life on days preceded by nights with asymptomatic (but not symptomatic) hypoglycaemia. The effect was amplified by lower glucose nadir and longer duration of the episodes and may help explain resistance to implementation of interventions to reduce hypoglycaemia in many people with impaired hypoglycaemia awareness.

Hypothalamic insulin signalling as a nexus regulating mood and metabolism

Insulin has long been known as a metabolic hormone critical in the treatment of diabetes for its peripheral effects on blood glucose. However, in the last 50 years, insulin has entered the realm of neuroendocrinology and many studies have described its function on insulin receptors in the brain in relation to both metabolic and mood disorders. Indeed, rodent models of impaired insulin signalling show signs of dysregulated energy and glucose homeostasis, as well as anxiety-like and depressive behaviours. Importantly, many metabolic diseases such as obesity and diabetes increase the risk of developing mood disorders; however, the brain mechanisms underlying the connection between metabolism and mood remain unresolved. We present the current literature on the importance of the insulin receptor with respect to regulating glucose and energy homeostasis and mood-related behaviours. Specifically, we hypothesise that the insulin receptor in the hypothalamus, classically known as the homeostatic centre of the brain, plays a causal role in linking metabolic and behavioural effects of insulin signalling. In this review, we discuss insulin signalling in the hypothalamus as a critical point of neural integration controlling metabolism and mood.

Impact of CGM on the Management of Hypoglycemia Problems: Overview and Secondary Analysis of the HypoDE Study

Hypoglycemia remains the limiting factor of near-normal glucose control in people with diabetes using insulin therapy. Continuous glucose monitoring (CGM) may be able to avoid hypoglycemia and support the management of hypoglycemia problems in clinical care. Real-time continuous glucose monitoring (rtCGM) systems provide alerts if certain predetermined hypo- or hyperglycemic thresholds are exceeded. The combination of rtCGM systems with insulin pumps allows insulin delivery to be suspended if glucose falls below certain predefined thresholds. This might also support avoidance of hypoglycemia. More sophisticated closed-loop systems allow a semiautomatic insulin dosage, which also have the potential for the prevention of hypoglycemia. In this overview, we discuss and illustrate (1) the efficacy of CGM for intervention in people with hypoglycemia problems and for the avoidance of biochemical as well as clinical hypoglycemia; (2) the potential of CGM technology for the identification of people with diabetes who are at risk for hypoglycemia problems; and (3) the implications of the current state of the art for future research regarding CGM and hypoglycemia. As an example, how rtCGM data can facilitate identification of people with diabetes and an elevated risk of hypoglycemia, a secondary analysis of the HypoDE data is presented. We conclude that CGM technology can assist in the reliable identification of people with diabetes who are at risk for hypoglycemia problems, is a powerful intervention for the avoidance of mild as well as severe hypoglycemia, and can also stimulate research on the course of hypoglycemia problems.

Adolescents with Type 1 diabetes mellitus experience psychosensorial symptoms during hypoglycaemia

AIM

To describe mood and psychosensorial symptoms of hypoglycaemia in adolescents with Type 1 diabetes mellitus in two countries with different cultures, Turkey and the USA.

METHODS

We developed a 68-item questionnaire assessing physical, behavioural, mood and psychosensorial symptom frequency and ratings ['good', 'bad', or 'both' (sometimes good, sometimes bad)]. Adolescents with Type 1 diabetes were recruited from paediatric diabetes clinics at the University of North Carolina at Chapel Hill in the USA and Kocaeli University in Turkey. The percentages of participants at each clinic who endorsed individual symptoms, symptom categories and symptom ratings were calculated and compared.

RESULTS

Cronbach's α values were > 0.7 for each real symptom category. No symptom items were excluded from the questionnaire analysis based on item-total correlation results which were all > 0.2. Data were collected from 132 participants (69 from University of North Carolina, 63 from Kocaeli University, 54% male). The mean (SD) age of the participants was 14.9 (1.9) years, HbA1c level was 8.7 (1.8) % and duration of Type 1 diabetes was 5.8 (3.7) years. On average, each physical symptom was experienced by 65.2% of participants, each behavioural symptom by 46.5%, each mood symptom by 42.8%, and each psychosensorial symptom by 48.9%. On average, each physical, behavioral, mood and psychosensorial symptom was rated as 'good' or 'both' by 23.0, 29.1, 36.9 and 37.2% of participants, respectively. There were no symptom differences between the groups in each country.

CONCLUSIONS

In addition to the classic physical symptoms experienced during hypoglycaemia, adolescents with Type 1 diabetes report psychosensorial, mood and behavioral symptoms, and some describe them as positive experiences. Symptom experiences were similar in these two countries with different cultures.

Diabetes and driving

The principal safety concern for driving for people treated with insulin or insulin secretagogues is hypoglycaemia, which impairs driving performance. Other complications, such as those causing visual impairment and peripheral neuropathy, are also relevant to medical fitness to drive. Case control studies have suggested that drivers with diabetes pose a modestly increased but acceptable and measurable risk of motor vehicle accidents compared to non-diabetic drivers, but many studies are limited and of poor quality. Factors which have been shown to increase driving risk include previous episodes of severe hypoglycaemia, previous hypoglycaemia while driving, strict glycaemic control (lower HbA1c) and absence of blood glucose monitoring before driving. Impaired awareness of hypoglycaemia may be counteracted by frequent blood glucose testing. The European Union Third directive on driving (2006) has necessitated changes in statutory regulations for driving licences for people with diabetes in all European States, including the UK. Stricter criteria have been introduced for Group 1 vehicle licences while those for Group 2 licences have been relaxed. Insulin-treated drivers can now apply to drive Group 2 vehicles, but in the UK must meet very strict criteria and be assessed by an independent specialist to be issued with a 1-year licence.

Mechanisms of the blunting of the sympatho-adrenal response: a theory

Development of therapeutic measures to reduce the risk of potentially fatal episodes of hypoglycaemia and thus to achieve the full benefits of intensive insulin therapy in diabetic patients requires a complete understanding of the multi-factorial mechanisms for repeated hypoglycaemia-induced blunting of the sympatho-adrenal response (BSAR). After critical analysis of the hypotheses, this review paper suggests a heuristic theory. This theory suggests two mechanisms for the BSAR, each involving a critical role for the central brain noradrenergic system. Furthermore, this theory also suggests that the lateral hypothalamus (LH) plays an important role in this phenomenon. Within the framework of this theory, explanations for 1) sexual dimorphism in the adrenomedullary response (AR), 2) dissociation in the blunting of the AR and the sympathetic response (SR) and 3) antecedent exercise-induced blunting of the AR are provided. In addition, habituation of orexin-A neurons is suggested to cause defective awakening. Moreover, potential therapeutics measures have been also suggested that will reduce or prevent severe episodes of hypoglycaemia.

Association of glucose levels and glucose variability with mood in type 1 diabetic patients

AIMS/HYPOTHESIS

The aim of this study was to investigate the association of glucose levels and variability of glucose, assessed by continuous glucose monitoring, with mood in type 1 diabetic patients.

MATERIALS AND METHODS

Thirty-six type 1 diabetic patients (77.8% male, age: 31.1 +/- 10.0 years; disease duration: 14.7 +/- 7.1 years, BMI: 26.7 +/- 5.1 kg/m2, HbA1c 8.4 +/-1.8%, 27.8% with continuous subcutaneous insulin infusion [CSII] therapy) used a continuous glucose monitoring system for 48.8 h. During this time the patients rated their current mood states 14.6 times on average, using the University of Wales Institute of Science and Technology Mood Adjective Checklist and hand-held computers.

RESULTS

Sensor performance was satisfactory, with a mean absolute difference from reference laboratory glucose measurement of 13.7%. Current glucose values were significantly associated with ratings of 'tension' (z = 2.40), 'hedonic tone' (z = -2.63) and 'energetic arousal' (z = -2.09). 'Anger' (z = 1.64) was not significantly associated with glucose values. The glucose AUC during the 60 min prior to the mood rating showed similar associations. The two parameters of glucose variability-coefficient of variation and absolute glucose change during the 60 min prior to the mood ratings-did not show any significant association with the mood ratings. The magnitude of association was significantly higher for glucose level than for glucose variability in the scales 'tension' and 'hedonic tone'.

CONCLUSIONS/INTERPRETATION

High glucose values had a negative impact on mood; positive mood ratings decreased, whereas negative mood ratings increased. The association between mood and glucose variability seemed to be less important than that between glucose level and mood.

Management of diabetes-related hypoglycemia

Iatrogenic hypoglycemia is the main factor limiting aggressive and optimal diabetes management. Rather than being an inevitable consequence of optimal glycemic control, however, hypoglycemia is avoidable and generally straightforward to manage when it occurs. Professional caregivers, patients, and their families are often fearful of hypoglycemia, even though most episodes are minor and easily self-treated. Understanding the factors contributing to hypoglycemia risk and how to minimize its occurrence is an essential part of diabetes care. Building on the physiologic fundamentals presented in the accompanying review, the incidence, mortality/morbidity, clinical symptoms, severity classification, and psychosocial impact of hypoglycemia are described here. Appropriate selection and titration of therapeutic agents, including insulin analogs with more predictable time-action profiles than human insulin formulations, can reduce hypoglycemia risk. Patient education about hypoglycemia prevention, including symptom recognition and necessity of rapid treatment, behavioral modification, and the importance of frequent blood glucose monitoring should accompany all therapeutic interventions.

Sensors and Sensor Systems for Psychophysiological Monitoring

Abstract. There are a wide range of sensors for acquiring signals from the human body in noninvasive ways. Some of those in use date back a few decades, and many new technologies have enabled different sensors designs in recent years. This review covers the following classes of sensors: electric, magnetic, electrochemical, mechanical, thermal, and optical. Sensor systems that are portable, safe, and low-cost are now becoming possible. This review provides an overview focussing on the technology behind sensors currently used by psychophysiologists with the objective of illuminating the choices available for acquiring signals that inform us about cognitive processes, emotional states, and behavioural patterns. In previously published encyclopaedic-type reviews of psychophysiology, the focus has been on what is measured, not how it is measured. By focussing on how the sensors and sensor systems work, this review aims to provide users of these technologies with information that will help them decide on the appropriate sensor to use, as well as to facilitate innovation and development of new sensors.