The incidence of severe hypoglycemia in type 1 diabetes has not decreased over the past decades. New treatment modalities minimizing the risk of hypoglycemic episodes and attenuating hypoglycemic cognitive dysfunction are needed. We studied if treatment with the neuroprotective hormone erythropoietin (EPO) enhances cognitive function during hypoglycemia.
Materials and Methods
Eleven patients with type 1 diabetes, hypoglycemia unawareness and recurrent severe hypoglycemia completed the study. In a double-blind, randomized, balanced, cross-over study using clamped hypoglycemia they were treated with 40,000 IU of EPO or placebo administered intravenously six days before the two experiments. Cognitive function (primary endpoint), hypoglycemic symptoms, and counter-regulatory hormonal response were recorded.
Compared with placebo, EPO treatment was associated with a significant reduction in errors in the most complex reaction time task (−4.7 (−8.1 to −1.3), p = 0.01) and a less reaction time prolongation (−66 (−117 to −16) msec, p = 0.02). EPO treatment did not change performance in other measures of cognition. Hypoglycemic symptoms, EEG-changes, and counter-regulatory hormone concentrations did not differ between EPO and placebo treatment.
In patients with type 1 diabetes and hypoglycemia unawareness, treatment with EPO is associated with a beneficial effect on cognitive function in a complex reaction time task assessing sustained attention/working memory. Hypoglycemic symptoms and hormonal responses were not changed by EPO treatment.
Hypoglycemia is a common finding in both daily clinical practice and acute care settings. The causes of severe hypoglycemia (SH) are multi-factorial and the major etiologies are iatrogenic, infectious diseases with sepsis and tumor or autoimmune diseases. With the advent of aggressive lowering of HbA1c values to achieve optimal glycemic control, patients are at increased risk of hypoglycemic episodes. Iatrogenic hypoglycemia can cause recurrent morbidity, sometime irreversible neurologic complications and even death, and further preclude maintenance of euglycemia over a lifetime of diabetes. Recent studies have shown that hypoglycemia is associated with adverse outcomes in many acute illnesses. In addition, hypoglycemia is associated with increased mortality among elderly and non-diabetic hospitalized patients. Clinicians should have high clinical suspicion of subtle symptoms of hypoglycemia and provide prompt treatment. Clinicians should know that hypoglycemia is associated with considerable adverse outcomes in many acute critical illnesses. In order to reduce hypoglycemia-associated morbidity and mortality, timely health education programs and close monitoring should be applied to those diabetic patients presenting to the Emergency Department with SH. ED disposition strategies should be further validated and justified to achieve balance between the benefits of euglycemia and the risks of SH. We discuss relevant issues regarding hypoglycemia in emergency and critical care settings.
Hypoglycemia; hyperglycemia; diabetes mellitus; emergency medicine; intensive care unit; anti-diabetic agents; insulin
Hypoglycemia is a cause of significant morbidity among patients with diabetes and may be associated with greater risk of death. We conducted a retrospective study to determine whether patient self-report of severe hypoglycemia is associated with increased mortality.
RESEARCH DESIGN AND METHODS
Adult patients (N = 1,020) seen in a specialty diabetes clinic between August 2005 and July 2006 were questioned about frequency of hypoglycemia during a preencounter interview; 7 were lost to follow-up and excluded from analysis. Mild hypoglycemia was defined as symptoms managed without assistance, and severe hypoglycemia was defined as symptoms requiring external assistance. Mortality data, demographics, clinical characteristics, and Charlson comorbidity index (CCI) were obtained from the electronic medical record after 5 years. Patients were stratified by self-report of hypoglycemia at baseline, demographics were compared using the two-sample t test, and risk of death was expressed as odds ratio (95% CI). Associations were controlled for age, sex, diabetes type and duration, CCI, HbA1c, and report of severe hypoglycemia.
In total, 1,013 patients with type 1 (21.3%) and type 2 (78.7%) diabetes were questioned about hypoglycemia. Among these, 625 (61.7%) reported any hypoglycemia, and 76 (7.5%) reported severe hypoglycemia. After 5 years, patients who reported severe hypoglycemia had 3.4-fold higher mortality (95% CI 1.5–7.4; P = 0.005) compared with those who reported mild/no hypoglycemia.
Self-report of severe hypoglycemia is associated with 3.4-fold increased risk of death. Patient-reported outcomes, including patient-reported hypoglycemia, may therefore augment risk stratification and disease management of patients with diabetes.
Hypoglycemia is associated with failure to show cardiovascular benefit and increased mortality of intensive glycemic control in randomized clinical trials. This retrospective cohort study aimed to examine the impact of hypoglycemia on vascular events in clinical practice.
RESEARCH DESIGN AND METHODS
Patients with type 2 diabetes were identified by ICD-9-CM codes (250.xx except for 250.x1 and 250.x3) between 1 January 2004 and 1 September 2010 from the Veterans Integrated Service Network 16. Index date was defined as the first date of new antihyperglycemic medications (index treatment). Patients with 1-year preindex records of hypoglycemia, cardiovascular, and microvascular diseases were excluded. The hypoglycemia group was identified by ICD-9-CM codes (250.8, 251.0, 251.1, and 251.2) within the index treatment period. A propensity score–matched group was used as control subjects. Cardiovascular events, microvascular complications, and all-cause death were compared using Kaplan-Meier analysis and Cox proportional hazards regression model.
Among the unmatched sample (N = 44,261), the hypoglycemia incidence rate was 3.57/100 patient-years. The matched sample (hypoglycemia group: n = 761; control group: n = 761) had a median follow-up of 3.93 years, mean age of 62.6 ± 11.0 years, and preindex HbA1c of 10.69 ± 2.61%. The 1-year change in HbA1c was similar (hypoglycemia group −0.51 vs. control group −0.32%, P = 0.7244). The hypoglycemia group had significantly higher risks of cardiovascular events (hazard ratio 2.00 [95% CI 1.63–2.44]) and microvascular complications (1.76 [1.46–2.11]) but no statistical mortality difference. Patients with at least two hypoglycemic episodes were at higher risks of vascular events than those with one episode (1.53 [1.10–1.66]).
Hypoglycemia is associated with higher risks of incident vascular events. Patients with hypoglycemia should be monitored closely for vascular events.
We hypothesize that in patients with insulin-dependent diabetes mellitus (IDDM), recent antecedent iatrogenic hypoglycemia is a major cause of hypoglycemia-associated autonomic failure, a disorder distinct from classical diabetic autonomic neuropathy (CDAN), and that hypoglycemia-associated autonomic failure, by reducing both symptoms of and defense against developing hypoglycemia, results in recurrent iatrogenic hypoglycemia, thus creating a vicious cycle. We used the hyperinsulinemic (12.0 pmol.kg-1.min-1) stepped hypoglycemic clamp technique to assess autonomic and symptomatic responses to hypoglycemia and the insulin infusion test (4.0 pmol.kg-1.min-1) to assess defense against hypoglycemia on mornings before and after clamped afternoon hypoglycemia (approximately 2.8 mmol/liter) and hyperglycemia (approximately 11.1 mmol/liter) in patients with IDDM. Compared with nondiabetic subjects, IDDM with or without CDAN exhibited reduced epinephrine (P = 0.0222 and 0.0040) and pancreatic polypeptide (P = 0.0083 and 0.0056) responses to hypoglycemia. After afternoon hypoglycemia, lower plasma glucose concentrations were required to elicit autonomic and symptomatic responses during morning hypoglycemic clamps in patients without CDAN. At the 2.8 mmol/liter step, mean (+/- SE) epinephrine levels were 1,160 +/- 270 and 2,040 +/- 270 pmol/liter (P = 0.0060), pancreatic and total symptom scores were 22 +/- 3 and 41 +/- 7 (P = 0.0475) after afternoon hypoglycemia and hyperglycemia, respectively. During morning insulin infusion tests after afternoon hypoglycemia, nadir plasma glucose concentrations were 2.6 +/- 0.2 mmol/liter compared with 3.3 +/- 0.3 mmol/liter (P < 0.001) at the corresponding time points after afternoon hyperglycemia. Thus, we conclude: (a) elevated glycemic thresholds for autonomic responses to hypoglycemia are a feature of IDDM per se, not classical diabetic autonomic neuropathy; and (b) a single episode of afternoon hypoglycemia results in both elevated glycemic thresholds for autonomic and symptomatic responses to hypoglycemia and impaired physiological defense against hypoglycemia the next morning in IDDM.
Hypoglycemia is a major barrier to achieving glycemic goals in patients with diabetes. Both acute and chronically recurrent hypoglycemic events appear to have long-term consequences for patients with type 2 diabetes mellitus (T2DM). Chronically recurrent hypoglycemia may lead to an impairment of the counterregulatory system, with the potential for the development of hypoglycemia unawareness syndrome, increased severe hypoglycemia-associated hospitalization, and increased mortality. Hypoglycemic events may also have negative implications in cardiovascular disease and/or dementia. Avoidance of hypoglycemia by treating with appropriate, individualized regimens for patients with T2DM should be a primary focus of physicians. Utilizing traditional agents (eg, metformin and thiazolidinediones) that do not promote hypoglycemia, in combination with newer agents such as dipeptidyl peptidase-4 inhibitors and incretin mimetics, could offer a therapeutic advantage when trying to help patients reach their hemoglobin A1c goal without the added risk of hypoglycemia.
hypoglycemia; type 2 diabetes mellitus; incretin; dipeptidyl peptidase-4 inhibitors; diabetes management
Hypoglycemia-associated autonomic failure (HAAF) constitutes one of the main clinical obstacles to optimum treatment of type 1 diabetes. Neurons in the ventromedial hypothalamus are thought to mediate counterregulatory responses to hypoglycemia. We have previously hypothesized that hypoglycemia-induced hypothalamic angiotensin might contribute to HAAF, suggesting that the angiotensin blocker valsartan might prevent HAAF. On the other hand, clinical studies have demonstrated that the opioid receptor blocker naloxone ameliorates HAAF. The goal of this study was to generate novel hypothalamic markers of hypoglycemia and use them to assess mechanisms mediating HAAF and its reversal.
RESEARCH DESIGN AND METHODS
Quantitative PCR was used to validate a novel panel of hypothalamic genes regulated by hypoglycemia. Mice were exposed to one or five episodes of insulin-induced hypoglycemia, with or without concurrent exposure to valsartan or naloxone. Corticosterone, glucagon, epinephrine, and hypothalamic gene expression were assessed after the final episode of hypoglycemia.
A subset of hypothalamic genes regulated acutely by hypoglycemia failed to respond after repetitive hypoglycemia. Responsiveness of a subset of these genes was preserved by naloxone but not valsartan. Notably, hypothalamic expression of four genes, including pyruvate dehydrogenase kinase 4 and glycerol 3-phosphate dehydrogenase 1, was acutely induced by a single episode of hypoglycemia, but not after antecedent hypoglycemia; naloxone treatment prevented this failure. Similarly, carnitine palmitoyltransferase-1 was inhibited after repetitive hypoglycemia, and this inhibition was prevented by naloxone. Repetitive hypoglycemia also caused a loss of hypoglycemia-induced elevation of glucocorticoid secretion, a failure prevented by naloxone but not valsartan.
Based on these observations we speculate that acute hypoglycemia induces reprogramming of hypothalamic metabolism away from glycolysis toward β-oxidation, HAAF is associated with a reversal of this reprogramming, and naloxone preserves some responses to hypoglycemia by preventing this reversal.
To characterize the amount of nocturnal hypoglycemia and evaluate factors associated with nocturnal hypoglycemia assessed with continuous glucose monitoring (CGM) in adults and children with type 1 diabetes who participated in the Juvenile Diabetes Research Foundation CGM randomized clinical trial.
RESEARCH DESIGN AND METHODS
The analysis included 36,467 nights with ≥4 h of CGM glucose readings between 12 midnight and 6:00 a.m. from 176 subjects assigned to the CGM group of the trial. The percentage of nights in which hypoglycemia occurred (two consecutive CGM readings ≤60 mg/dl in 20 min) was computed for each subject. Associations with baseline characteristics and clinical factors were evaluated using a multivariate regression model.
Hypoglycemic events occurred during 8.5% of nights, with the median percentage of nights with hypoglycemia per subject being 7.4% (interquartile range 3.7–12.1%). The duration of hypoglycemia was ≥2 h on 23% of nights with hypoglycemia. In a multivariate model, a higher incidence of nocturnal hypoglycemia was associated with 1) lower baseline A1C levels (P < 0.001) and 2) the occurrence of hypoglycemia on one or more nights during baseline blinded CGM (P < 0.001). The hypoglycemia frequency was not associated with age or with insulin modality (pump versus multiple daily injections).
Nocturnal hypoglycemia is frequent and often prolonged in adults and children with type 1 diabetes. Patients with low A1C levels are at an increased risk for its occurrence. One week of blinded CGM can identify patients who are at greater risk for nocturnal hypoglycemia.
Hypoglycemia is an important complication of glucose-lowering therapy in patients with diabetes mellitus. Attempts made at intensive glycemic control invariably increases the risk of hypoglycemia. A six-fold increase in deaths due to diabetes has been attributed to patients experiencing severe hypoglycemia in comparison to those not experiencing severe hypoglycemia Repeated episodes of hypoglycemia can lead to impairment of the counter-regulatory system with the potential for development of hypoglycemia unawareness. The short- and long-term complications of diabetes related hypoglycemia include precipitation of acute cerebrovascular disease, myocardial infarction, neurocognitive dysfunction, retinal cell death and loss of vision in addition to health-related quality of life issues pertaining to sleep, driving, employment, recreational activities involving exercise and travel. There is an urgent need to examine the clinical spectrum and burden of hypoglycemia so that adequate control measures can be implemented against this neglected life-threatening complication. Early recognition of hypoglycemia risk factors, self-monitoring of blood glucose, selection of appropriate treatment regimens with minimal or no risk of hypoglycemia and appropriate educational programs for healthcare professionals and patients with diabetes are the major ways forward to maintain good glycemic control, minimize the risk of hypoglycemia and thereby prevent long-term complications.
Diabetes mellitus; glucagon; hypoglycemia; hypoglycemia unawareness; insulin; management; physiologic impact; quality of life
Hypoglycemia, the limiting factor in the glycemic management of diabetes, is the result of the interplay of therapeutic insulin excess and compromised glycemic defenses. The key feature of the latter is an attenuated sympathoadrenal response to hypoglycemia that typically follows an episode of recent antecedent iatrogenic hypoglycemia, a phenomenon termed hypoglycemia-associated autonomic failure (HAAF) in diabetes. We investigated the role of cerebral mechanisms in HAAF by measuring regional brain activation during recurrent hypoglycemia with attenuated counterregulatory responses and comparing it to initial hypoglycemia in healthy individuals.
Research Design and Methods
We used [15O]water and positron emission tomography to measure regional cerebral blood flow (CBF) as a marker of brain synaptic activity during hyperinsulinemic hypoglycemic clamps (55 mg/dL [3.0 mmol/L]) in the naïve condition (Day 1) and after ∼24 hours of interval interprandial hypoglycemia (Day 2) in nine healthy adults.
Interval hypoglycemia produced attenuated sympathoadrenal, symptomatic and other counterregulatory responses to hypoglycemia on Day 2, a model of HAAF. Synaptic activity in the dorsal midline thalamus during hypoglycemia was significantly greater on Day 2 than Day 1 (P=0.004).
Greater synaptic activity associated with attenuated counterregulatory responses indicates that the dorsal midline thalamus plays an active inhibitory role in reducing sympathoadrenal and symptomatic responses to hypoglycemia when previous hypoglycemia has occurred, the key feature of HAAF in diabetes.
Hypoglycemia; Diabetes; Hypoglycemia-Associated Autonomic Failure; Positron Emission Tomography; Thalamus
We sought to develop descriptions of health states associated with daytime and nocturnal hypoglycemia in a structured fashion from the patient’s perspective under different combinations of severity and frequency of hypoglycemic events.
An expert meeting followed by two patient focus groups was used to develop comprehensive descriptions of acute consequences of severe and non-severe, daytime and nocturnal hypoglycemia. Patients with diabetes (type 1 = 85, type 2 = 162) from a survey panel then validated these descriptions and assessed how often they worried and took different actions to prevent hypoglycemia. Severity and frequency of hypoglycemia were compared with respect to how often people worried and took actions to prevent an event. The effect of hypoglycemia on 35 different life activities was quantitatively compared for patients who had and had not experienced a severe hypoglycemic event.
At least 95% of respondents agreed that the detailed patient-level descriptions of health states accurately reflected their experience of severe and non-severe, daytime and nocturnal hypoglycemia, thereby validating these descriptions. Respondents who had experienced a severe hypoglycemic event were generally more adversely affected in their worries and actions and life events than those who experienced only non-severe events; those who experienced nocturnal events were more affected than those who experienced only daytime events.
The negative psychosocial consequences and undesirable compensatory behaviors arising from hypoglycemia underscore the importance of preventing severe episodes, particularly severe nocturnal episodes. These validated descriptions for hypoglycemia from the patient’s perspective may also help inform future qualitative and quantitative research.
hypoglycemia; health states; diabetes; quality of life
Current recommendations are that people with Type 1 and Type 2 diabetes mellitus exercise regularly. However, in cases in which insulin or insulin secretagogues are used to manage diabetes, patients have an increased risk of developing hypoglycemia, which is amplified during and after exercise. Repeated episodes of hypoglycemia blunt autonomic nervous system, neuroendocrine and metabolic defenses (counter-regulatory responses) against subsequent episodes of falling blood glucose levels during exercise. Likewise, antecedent exercise blunts counter-regulatory responses to subsequent hypoglycemia. This can lead to a vicious cycle, by which each episode of either exercise or hypoglycemia further blunts counter-regulatory responses. Although contemporary insulin therapies cannot fully mimic physiologic changes in insulin secretion, people with diabetes have several management options to avoid hypoglycemia during and after exercise, including regularly monitoring blood glucose, reducing basal and/or bolus insulin, and consuming supplemental carbohydrates.
exercise; hypoglycemia; hypoglycemia-associated autonomic failure; insulin; insulin secretagogues; physical activity; Type 1 diabetes mellitus; Type 2 diabetes mellitus
The majority of cases of post-prandial reactive hypoglycemia are considered idiopathic. Abnormalities of B-cell function and glucose regulation by insulin and glucagon have been postulated as causes but associated gastrointestinal dysfunction has not been reported. We report the first case of accelerated gastric emptying associated with post-prandial reactive hypoglycemia, abdominal bloating and diarrhea. We consider that gastric dysmotility is an important cause of this condition as treatment of the underlying abnormal gastric emptying allows effective control of symptoms.
A 20-year-old Caucasian woman presented with post-prandial fatigue, sweating, nausea, faintness and intermittent confusion, which had led to pre-syncope and syncope on occasions. She also experienced marked abdominal bloating and diarrhea over the same period. These episodes responded to oral administration of sweet drinks. Her symptoms were ameliorated by modification of her diet.
This is an original case report of the association of idiopathic accelerated gastric emptying with post-prandial reactive hypoglycemia and diarrhea. Family physicians, endocrinologists and gastroenterologists often consult patients with a constellation of post-prandial symptoms, which are considered to be idiopathic in most cases. This case indicates that gastric dysmotility might be the primary cause of these symptoms in some patients and, if found, offers a therapeutic target which in our case was successful.
To improve outcomes for patients with many serious clinical problems, multifactorial research approaches by nurse scientists, including the use of animal models, are necessary. Animal models serve as analogies for clinical problems seen in humans and must meet certain criteria, including validity and reliability, to be useful in moving research efforts forward. This article describes research considerations in the development of rodent models. As the standard of diabetes care evolves to emphasize intensive insulin therapy, rates of severe hypoglycemia are increasing among patients with type 1 and type 2 diabetes mellitus. A consequence of this change in clinical practice is an increase in rates of two hypoglycemia-related diabetes complications: hypoglycemia-associated autonomic failure (HAAF) and resulting hypoglycemia unawareness. Work on an animal model of HAAF is in an early developmental stage, with several labs reporting different approaches to model this complication of type 1 diabetes mellitus. This emerging model serves as an example illustrating how evaluation of validity and reliability is critically important at each stage of developing and testing animal models to support inquiry into human disease.
translational research; animal models; hypoglycemia unawareness; diabetes complications
The aim of this study was to examine the relationship between frequent and unrecognized hypoglycemia and mortality in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study cohort.
RESEARCH DESIGN AND METHODS
A total of 10,096 ACCORD study participants with follow-up for both hypoglycemia and mortality were included. Hazard ratios (95% CIs) relating the risk of death to the updated annualized number of hypoglycemic episodes and the updated annualized number of intervals with unrecognized hypoglycemia were obtained using Cox proportional hazards regression models, allowing for these hypoglycemia variables as time-dependent covariates and controlling for the baseline covariates.
Participants in the intensive group reported a mean of 1.06 hypoglycemic episodes (self-monitored blood glucose <70 mg/dL or <3.9 mmol/L) in the 7 days preceding their regular 4-month visit, whereas participants in the standard group reported an average of 0.29 episodes. Unrecognized hypoglycemia was reported, on average, at 5.8% of the intensive group 4-month visits and 2.6% of the standard group visits. Hazard ratios for mortality in models including frequency of hypoglycemic episodes were 0.93 (95% CI 0.9–0.97; P < 0.001) for participants in the intensive group and 0.98 (0.91–1.06; P = 0.615) for participants in the standard group. The hazard ratios for mortality in models, including unrecognized hypoglycemia, were not statistically significant for either group.
Recognized and unrecognized hypoglycemia was more common in the intensive group than in the standard group. In the intensive group of the ACCORD study, a small but statistically significant inverse relationship of uncertain clinical importance was identified between the number of hypoglycemic episodes and the risk of death among participants.
Iatrogenic hypoglycemia, typically the result of the interplay of therapeutic hyperinsulinemia and compromised defenses resulting in hypoglycemia-associated autonomic failure (HAAF) in diabetes, is a problem for people with T1DM. It causes recurrent morbidity and is sometimes fatal, leads to recurrent hypoglycemia, and precludes euglycemia over a lifetime of T1DM. Risk factors include those that result in relative or absolute insulin excess and those indicative of HAAF in diabetes including absolute endogenous insulin deficiency, a history of severe hypoglycemia, hypoglycemia unawareness, or both, and lower glycemic goals. Minimizing the risk of hypoglycemia involves matching insulin action and glucose availability and four specific steps: 1) acknowledge the problem, 2) apply the principles of aggressive glycemic therapy, 3) consider the conventional risk factors, and 4) consider the risk factors indicative of HAAF. Treatment of hypoglycemia is usually accomplished by ingestion of carbohydrate by the patient. Sometimes it involves administration of glucagon or infusion of glucose by others. Elimination of hypoglycemia from the lives of people with T1DM will likely be accomplished by new treatment methods that provide plasma glucose regulated insulin replacement or secretion.
Hypoglycemia; Diabetes; Defective Glucose Counterregulation; Hypoglycemia Unawareness; Hypoglycemia-Associated Autonomic Failure in Diabetes
Self-management of type 2 diabetes including avoidance of hypoglycemia is complex, but the impact of cognition on safe self-management is not well understood. This study aimed to assess the effect of baseline cognitive function and cognitive decline on subsequent risk of severe hypoglycemia and to assess the effect of different glycemic strategies on these relationships.
RESEARCH DESIGN AND METHODS
Prospective cohort analysis of data from the ACCORD trial included 2,956 adults aged ≥55 years with type 2 diabetes and additional cardiovascular risk factors. Cognitive tests (Digit Symbol Substitution Test [DSST], Rey Auditory Verbal Learning Test, Stroop Test, and Mini Mental Status Examination) were conducted at baseline and 20 months. Study outcomes were incident confirmed severe hypoglycemia requiring medical assistance (HMA) and hypoglycemia requiring any assistance (HAA).
After a median 3.25-year follow-up, a 5-point-poorer baseline score on the DSST was predictive of a first episode of HMA (hazard ratio 1.13 [95% CI 1.08–1.18]). Analyses of the other cognitive tests and of HAA were consistent with the DSST results. Cognitive decline over 20 months increased the risk of subsequent hypoglycemia to a greater extent in those with lower baseline cognitive function (Pinteraction = 0.037). Randomization to an intensive versus standard glycemic strategy had no impact on the relationship between cognitive function and the risk of severe hypoglycemia.
Poor cognitive function increases the risk of severe hypoglycemia in patients with type 2 diabetes. Clinicians should consider cognitive function in assessing and guiding their patients regarding safe diabetes self-management regardless of their glycemic targets.
Although tight glucose control is widely used in hospitalized patients, there is concern that medication-induced hypoglycemia may worsen patient outcomes. We sought to determine if the mortality risk associated with hypoglycemia in hospitalized non-critically ill patients is linked to glucose-lowering medications (drug-associated hypoglycemia) or if it is merely an association mediated by comorbidities (spontaneous hypoglycemia).
Retrospective cohort of patients admitted to the general wards of an academic center during 2007. The in-hospital mortality risk of a hypoglycemic group (at least one blood glucose ≤ 70 mg/dl) was compared to that of a normoglycemic group using survival analysis. Stratification by subgroups of patients with spontaneous and drug-associated hypoglycemia was performed.
Among 31,970 patients, 3,349 (10.5%) had at least one episode of hypoglycemia. Patients with hypoglycemia were older, had more comorbidities, and received more antidiabetic agents. Hypoglycemia was associated with increased in-hospital mortality (HR: 1.67, 95% CI, 1.33 to 2.09, p<0.001). However, this greater risk was limited to patients with spontaneous hypoglycemia (HR: 2.62, 95% CI, 1.97 to 3.47, p<0.001), not to those with drug-associated hypoglycemia (HR: 1.06, 95% CI, 0.74 to 1.52, p=0.749). After adjustment for patient comorbidities, the association between spontaneous hypoglycemia and mortality was eliminated (HR: 1.11, 95% CI, 0.76 to 1.64, p=0.582).
Drug-associated hypoglycemia was not associated with increased mortality risk in patients admitted to the general wards. The association between spontaneous hypoglycemia and mortality was eliminated after adjustment for comorbidities, suggesting that hypoglycemia may be a marker of disease burden rather than a direct cause of death.
Hypoglycemia; mortality; hypoglycemia in general ward patients
This article reviews diagnosis and management of infants with diabetes. These infants present with signs and symptoms confused with other more common illnesses in this age group. A physician examining an ill-appearing dehydrated infant, without any obvious cause for the dehydration, should quickly screen the urine for glucose and ketones. Diagnosis of diabetes is a problem when an infant has only hyperglycemia or ketonuria. Febrile illnesses, convulsions, and dehydration can cause these laboratory abnormalities. Once the diagnosis of diabetes is made in the infant, management is complicated by the difficulty in administering small doses of insulin, monitoring blood glucose, complementing insulin administration with feedings, and hypoglycemia. The potential for brain damage with unrecognized episodes of hypoglycemia is always a concern in infants. This article offers suggestions for treating hypoglycemia as well as guidelines for making insulin adjustments when the infant is ill. The physician should be aware of the psychosocial issues involving the family of an infant with diabetes. Optimism and ongoing support should be provided to the family, so that the infant can grow up healthy and possibly benefit from research on the cure of diabetes.
To determine the prevalence and clinical associations of impaired awareness of hypoglycemia in a population-based sample of children and adolescents with type 1 diabetes.
RESEARCH DESIGN AND METHODS
A validated questionnaire was administered to 656 patients with type 1 diabetes over a 6-month period to determine hypoglycemia awareness status. Case ascertainment was 79% of the clinic population. The rate of severe hypoglycemia was determined by data collected prospectively in the preceding year.
Impaired awareness of hypoglycemia was present in 29% of patients. Patients with impaired awareness of hypoglycemia had an earlier onset of diabetes (P < 0.001), were younger (P < 0.001), and had lower mean levels of A1C since diabetes onset (P = 0.006) and at their last visit (P = 0.001). The overall rate of severe hypoglycemia was 24.5 episodes per 100 patient-years in the preceding year. The severe hypoglycemia rate was higher in those with impaired awareness of hypoglycemia (37.1 vs. 19.3 episodes per 100 patient-years, P < 0.001). Among patients aged <6 years (n = 46), 59% of care providers reported impaired awareness of hypoglycemia, and the rate of severe hypoglycemia was significantly higher in those reporting impaired awareness (33.3 vs. 52 episodes per 100 patient-years, P = 0.02). More patients with recurrent hypoglycemia reported impaired awareness of hypoglycemia (47 vs. 28%, P = 0.03).
A significant proportion of children and adolescents with type 1 diabetes have impaired awareness of hypoglycemia. Screening for impaired awareness is an important component of routine diabetes care and can identify patients at increased risk of a severe hypoglycemic event.
Hypoglycemia is the rate-limiting factor that often prevents patients with diabetes from safely and effectively achieving their glycemic goals. Recent studies have reported that severe hypoglycemia is associated with a significant increase in the adjusted risks of major macrovascular events, major microvascular events, and mortality. Minor hypoglycemic episodes can also have serious implications for patient health, psychological well being, and adherence to treatment regimens. Hypoglycemic events can impact the health economics of the patient, their employer, and third-party payers. Insulin treatment is a key predictor of hypoglycemia, with one large population-based study reporting an overall prevalence of 7.1% (type 1 diabetes mellitus) and 7.3% (type 2 diabetes mellitus) in insulin-treated patients, compared with 0.8% in patients with type 2 diabetes treated with an oral sulfonylurea. Patients with type 1 diabetes typically experience symptomatic hypoglycemia on average twice weekly and severe hypoglycemia once annually. The progressive loss of islet cell function in patients with type 2 diabetes results in a higher risk of both symptomatic and unrecognized hypoglycemia over time. Patients with diabetes who become hypoglycemic are also more susceptible to developing defective counter-regulation, also known as hypoglycemia awareness autonomic failure, which is life-threatening and must be aggressively addressed. In patients unable to recognize hypoglycemia symptoms, frequent home monitoring or use of continuous glucose sensors are critical. Primary care physicians play a key role in the prevention and management of hypoglycemia in patients with diabetes, particularly in those requiring intensive insulin therapy, yet physicians are often unaware of the multitude of consequences of hypoglycemia or how to deal with them. Careful monitoring, adherence to guidelines, and use of optimal treatment combinations are all important steps toward improving care in patients with diabetes. The most important goals are for primary care physicians to recognize that every patient treated with antihyperglycemic medications is at risk of iatrogenic hypoglycemia and to ask patients about hypoglycemia at every visit.
hypoglycemia; insulin analogs; type 1 diabetes mellitus; type 2 diabetes mellitus
To explore the use of Diabetes Symptom Checklist-Revised (DSC-R) Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia subscales as measures of acute diabetes-associated symptoms in patients with both type 1 and 2 diabetes.
Research design and methods
Our study was conducted in context of two international, multicenter, randomized clinical trials for inhaled insulin. Confirmatory factor analyses and assessments of reliability and construct validity were performed.
Study participants were 371 patients with type 2 (56% male; mean age, 57 years) and 481 with type 1 diabetes (57% male, mean age, 40 years). In both populations a four-factor model was the best fit. Cronbach’s α ≥ 0.79 and intraclass correlation coefficient ≥ 0.63; subscales correlated (P ≤ 0.05) with measures of well-being and satisfaction (0.12 ≤ r ≤ 0.71). In patients with type 1 diabetes, three subscales correlated (P < 0.05) with A1C.
The psychometric properties of the DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia suggest they may be utilized in clinical trials as reliable and valid measures of acute symptoms of diabetes.
Diabetes Symptom Checklist-Revised; DSC-R; type 1 diabetes; type 2 diabetes; psychometric validation
Background and Aim
We wished to establish the frequency of unexpected hypoglycemia observed in non diabetic patients outside the intensive care unit and to determine if they have a plausible clinical explanation.
We analysed data for 2010 from three distinct sources to identify non diabetic hypoglycaemic patients: bedside and laboratory blood glucose measurements; medication records for those treatments (high-strength glucose solution and glucagon) commonly given to reverse hypoglycemia; and diagnostic codes for hypoglycemia. We excluded from the denominator admissions of patients with a diagnosis of diabetes or prescribed diabetic medication. Case notes of patients identified were reviewed. We used capture-recapture methods to establish the likely frequency of hypoglycemia in non-diabetic in-patients outside intensive care unit at different cut-off points for hypoglycemia. We also recorded co-morbidities that might have given rise to hypoglycemia.
Among the 37,898 admissions, the triggers identified 71 hypoglycaemic episodes at a cut-off of 3.3 mmol/l. Estimated frequency at 3.3 mmol/l was 50(CI 33–93), at 3.0 mmol/l, 36(CI 24–64), at 2.7 mmol/l, 13(CI 11–19), at 2.5 mmol/l, 11(CI 9–15) and at 2.2 mmol/l, 8(CI 7–11) per 10,000 admissions. Admissions of patients aged above 65 years were approximately 50% more likely to have an episode of hypoglycemia. Most were associated with important co-morbidities.
Significant non-diabetic hypoglycemia in hospital in–patients (at or below 2.7 mmol/l) outside critical care is rare. It is sufficiently rare for occurrences to merit case-note review and diagnostic blood tests, unless an obvious explanation is found.
GH is implicated in the counter-regulatory response to hypoglycemia. We tested whether IGF1 levels are associated with occurrence of severe hypoglycemic events in patients with type 1 diabetes and whether the IGF1 concentration is influenced by glycemic control.
A total of 228 outpatients with type 1 diabetes were included in a post hoc analysis of a 1-year observational study on severe hypoglycemia. Serum total IGF1 was measured at entry into the study. The occurrence of severe episodes of hypoglycemia, mild symptomatic, and biochemical as well as hypoglycemia awareness status was assessed. Also patients were included in a multiple regression analysis to investigate the role of HbA1c in the IGF1 concentration.
IGF1 levels were associated with neither severe hypoglycemia in the entire cohort (P=0.30) nor in any gender nor when confining the analysis to those with long-standing diabetes (>20 years) (n=112, P=0.68) and those with both long-standing diabetes and undetectable C-peptide (n=51, P=0.067). Levels of IGF1 were associated with neither mild symptomatic hypoglycemia (P=0.24) nor biochemical hypoglycemia (0.089) nor hypoglycemia awareness (P=0.16). At a multiple regression analysis, HbA1c was negatively associated with IGF1 (P=0.001).
In type 1 diabetes, circulating IGF1 levels are negatively associated with glycemic control. However, IGF1 levels were not associated with occurrence of hypoglycemia or hypoglycemia awareness in these patients.
type 1 diabetes; IGF1; hypoglycemia; HbA1c
This study tested a model hypothesizing that treatment affects objective clinical outcomes, which in turn affect perceived consequences, which in turn affect satisfaction and preference judgments.
RESEARCH DESIGN AND METHODS
The model was tested in a double-blind, randomized clinical trial in which 266 patients with type 1 diabetes added active or placebo pramlintide to their insulin regimens. Objective clinical outcomes included changes in glucose and weight control, insulin requirements, incidence of hypoglycemia, and study drug tolerance. At the end of the trial, patients completed the validated PRAM-TSQ questionnaire measuring treatment satisfaction and preference and perceived medication benefits and side effects.
Statistical modeling demonstrated that active pramlintide was significantly associated with greater treatment satisfaction, preference, and perceived benefits (all except hypoglycemia prevention), as well as objective clinical outcomes (weight loss, lower postprandial glucose [PPG], lower medication tolerance, more hypoglycemia). Perceptions of treatment consequences were sensitive and specific to their cognate objective clinical outcomes (no halo effects). Clinical outcomes (especially PPG) accounted for almost half of the effect of the study medication on treatment satisfaction and preference. Treatment satisfaction and preference were strongly related to the perceived benefits/side effects of the study medication, and these perceptions (especially glucose control) mediated most of the association of clinical outcomes with satisfaction and preference.
This model received substantial empirical support. Improvements in objective clinical outcomes accounted for a large part of the association of pramlintide treatment with higher treatment satisfaction and preference. Perceived treatment consequences mediated the effect of objective clinical benefits on satisfaction with and preference for the study medication.