I. Hammana

No relationship between mean plasma glucose and glycated haemoglobin in patients with cystic fibrosis-related diabetes

AIM Cystic fibrosis-related diabetes (CFRD) prevalence has increased dramatically with the improved life expectancy of patients with cystic fibrosis (CF). Glycated haemoglobin (HbA(1c)) is an important tool for monitoring blood glucose control but, unlike in type 1 and type 2 diabetes, a correlation between HbA(1c), fructosamine and mean plasma glucose has not been clearly established in CF. This study aimed to examine the relationship between mean plasma glucose and HbA(1c) or fructosamine in stable patients with CFRD. METHODS Fifteen type 1 diabetes and 13 CFRD patients (HbA(1c)<9.0%; no anaemia), matched for age and body mass index (BMI), provided 72 capillary blood glucose profiles taken 3days/month for three months. At the end of this time, HbA(1c) and fructosamine were measured. Mean plasma glucose was estimated using the Diabetes Control and Complications Trial (DCCT) conversion formula, and linear regressions carried out to establish its relationship with HbA(1c) and fructosamine. RESULTS In type 1 diabetes patients, mean plasma glucose correlated significantly with HbA(1c) (r=0.68; P=0.005). In CFRD patients, no correlation was found between mean plasma glucose and HbA(1c) (r=0.24; P=0.460). Also, no association was found between mean plasma glucose, representing the month before blood sampling, and fructosamine in either group. CONCLUSION Unlike in type 1 diabetes, HbA(1c) did not correlate with mean plasma glucose in CFRD subjects. Thus, having a normal HbA(1c) may not be sufficient to indicate a low risk of diabetes complications in CFRD. Further studies are required to explain such a discrepancy.

Speech Recognition in the Radiology Department: A Systematic Review:

Objective: to conduct a systematic review of the literature describing the impact of speech recognition systems on report error rates and productivity in radiology departments. Methods: The search was conducted for relevant papers published from January 1992 to October 2013. Comparative studies reporting any of the following outcomes were selected: error rates, departmental productivity, and radiologist productivity. The retrieved studies were assessed for quality and risk of bias. Results: The literature search identified 85 potentially relevant publications, but, based on the inclusion and exclusion criteria, only 20 were included. Most studies were before and after assessments with no control group. There was a large amount of heterogeneity due to differences in the imaging modalities assessed and the outcomes measured. The percentage of reports containing at least one error varied from 4.8% to 89% for speech recognition, and from 2.1% to 22% for transcription. Departmental productivity was improved with decreases in report turnaround times varying from 35% to 99%. Most studies found a lengthening of radiologist dictation time. Conclusion: Overall gains in departmental productivity were high, but radiologist productivity, as measured by the time to produce a report, was diminished.

Validation of insulin secretion indices in cystic fibrosis patients.

BACKGROUND AND AIMS Impaired insulin secretion plays a key role in the development of cystic fibrosis-related diabetes (CFDR). Numerous indices to evaluate insulin secretion have been proposed, but their validity has not been explored in cystic fibrosis (CF). The aim of the present study was to validate surrogate indices of insulin secretion in CF patients against the gold standard, the intravenous glucose tolerance test (IVGTT). METHODS 32 subjects were enrolled: 16 controls, 10 cystic fibrosis-normal glucose tolerant (CF-NGT) and 6 CFRD patients. All subjects underwent a 2-h oral glucose tolerance test (OGTT) and an IVGTT. Insulin secretion was estimated using three indices: the HOMA-beta cell, the Stumvolls early insulin secretion, and the insulin secretion rate (ISR). RESULTS In control subjects, all insulin secretion indices correlated significantly with the IVGTT. In CF-NGT patients, the HOMA-beta cell correlated significantly with the IVGTT at shorter time points but not over longer time-period. On the other hand, both OGTT-derived indices (Stumvoll and IRS) correlated significantly with the IVGTT for the CF-NGT and CFRD groups. CONCLUSION Since the OGTT is required on a regular basis in CF patients to screen for CFRD, OGTT-derived indices appear to be suitable for evaluating insulin secretion.

Dichotomy between postprandial glucose and lipid profiles in adults with cystic fibrosis: A pilot study

BACKGROUND Cystic fibrosis (CF) patients present a high incidence of glucose tolerance abnormalities. Altered insulin secretion combined with recommended high-fat intake could be associated with dysregulation of glucose and lipid metabolism. We examined postprandial glucose and lipid profiles during an oral glucose tolerance test (OGTT) and following a standardized high-fat test meal (TM). METHODS Sixteen CF patients with normal glucose tolerance (NGT) or CF-related diabetes (CFRD) and 16 controls underwent a 4 h OGTT and a TM. We then measured plasma glucose, insulin, free fatty acid (FFA) and triglyceride (TG) concentrations. RESULTS CF patients presented higher glucose excursion compared to controls after the OGTT and TM. However, in CF patients, this excursion was significantly reduced in both amplitude and length after the TM. The TM provoked a comparable increase in TG levels in both groups whereas they remained stable during the OGTT. FFAs were suppressed similarly in both groups after both challenges. CONCLUSION CF is associated with abnormal glucose excursion in the presence of relatively normal lipid excursion. The rapid normalization of glucose values after a mixed meal should be further explored and, if confirmed, might have significant implications for CFRD diagnostic.

Variation of glucose tolerance in adult patients with cystic fibrosis: What is the potential contribution of insulin sensitivity?

BACKGROUND Reduced insulin secretion is a key factor to explain high prevalence of glucose intolerance in patients with cystic fibrosis (CF). However, the role of insulin sensitivity remains unclear. The aim of this study is to investigate the association of insulin secretion and sensitivity with the evolution of glucose tolerance. METHODS A total of 152 patients without known diabetes from the Montreal CF cohort underwent two 2-h oral glucose tolerance tests (OGTT) at baseline and again after 21.2±5.5months. Pulmonary function and anthropometric measurements were also collected at each visit. At both visits, based on their OGTT results, patients were categorized in glucose tolerance groups (normal glucose tolerance, impaired glucose tolerance or CF-related diabetes) and stratified in 3 groups according to the variation of their glucose tolerance: stable, improved or deteriorated. RESULTS At baseline, patients in the deteriorated group had a better sensitivity to insulin than those in the improved group (P=0.029). At follow-up glucose tolerance remained stable in 55.3%, improved in 14.5% and deteriorated in 30.3% of patients. During follow-up, insulin secretion remained stable in all 3 groups. While insulin sensitivity remained stable in patients without changes in glucose tolerance it worsened in patients who deteriorated glucose tolerance (P<0.001) and improved in patients who improved their glucose tolerance (P=0.003). CONCLUSION In a context of significantly reduced insulin secretion, variations of insulin sensitivity are associated with variations of glucose tolerance in adult patients with CF.

Normal total and high molecular weight adiponectin levels in adults with cystic fibrosis.

Cystic fibrosis related diabetes (CFRD) is an important complication of CF that increases mortality. Adiponectin, an adipokine secreted from adipose tissue, plays an important role in fatty acid and glucose metabolism. Lower total adiponectin (TA) levels have been linked to the risk of developing type 2 diabetes. However, studies show that the high molecular weight isoform (HMW), thought to be more active than TA, might be a better indicator of insulin sensitivity. Our aim was to determine the association between HMW and insulin sensitivity in CF subjects and determine if other factors might modulate its levels. Thirteen control subjects and 47 CF adults (16 with normal glucose tolerance, 16 prediabetic and 15 with CFRD) underwent an oral glucose tolerance test. Blood samples were taken at time 0, 30, 60, 90 and 120 min. Body mass index, fibrinogen, glucose and insulin, TA and HMW were measured in every subject. Regression analysis was used to determine the association between TA, HMW and glucose (fasting glucose, 2h glucose and glucose AUC) as well as insulin (fasting insulin, insulin AUC, and Stumvoll insulin sensitivity index) parameters. TA and HMW levels were similar between CF patients and controls and were not associated to insulin sensitivity. TA was negatively associated to insulin AUC (p=0.0108) and 2h glucose (p=0.0116) in controls while these relationships were either weakly negative (p=0.0208) or weakly positive (p=0.0105) in CF patients. Also, HMW was negatively associated to insulin (p=0.00301) and glucose AUC (p=0.0546) in controls whereas these associations were positive in CF patients (p=0.0388, p=0.0232 respectively). In conclusion, our exploratory study on HMW adiponectin demonstrated similar levels of TA and HMW between CF patients and controls and different relationships between forms of adiponectin to glucose metabolism and insulin in CF.

P83 Régulation de l’adiponectine chez les adultes atteints de mucoviscidose

Introduction La mucoviscidose est la maladie autosomique recessive la plus frequemment retrouvee chez la population caucasienne. Le diabete secondaire a la mucoviscidose est une complication importante de cette maladie et augmente le taux de mortalite des patients. L’adiponectine, un polypeptide secrete par les adipocytes, joue un role important dans le metabolisme des glucides et des lipides, dans le diabete de type 2 et augmente la sensibilite a l’insuline. L’adiponectine totale peut etre clivee pour devenir une forme de haut poids moleculaire et des etudes suggerent que le rapport de l’adiponectine de haut poids moleculaire et la forme non-clivee est un indicateur de la sensibilite a l’insuline chez les humains. L’objectif de cette etude est d’examiner la relation entre les concentrations plasmatiques d’adiponectine totale et de haut poids moleculaire ainsi que le rapport et la tolerance au glucose des adultes atteints de mucoviscidose afin d’explorer le role de l’adiponectine au niveau de la sensibilite a l’insuline. Patients et methodes Une hyperglycemie provoquee par voie orale a ete realisee chez 44 patients atteints de mucoviscidose avec differentes tolerances au glucose (normotolerants, intolerants ou diabetiques) et 13 sujets temoins apparies pour le sexe, l’âge et l’indice de masse corporelle. Nous avons ensuite doses les niveaux de glucose, d’insuline et d’adiponectine avec les echantillons plasmatiques. La sensibilite a l’insuline a ete verifiee a l’aide d’indices valides tels que le Stumvoll et le « homeostasis model assessment (HOMA) ». D’autres marqueurs biologiques tels que le fibrinogene et le cholesterol HDL ont aussi ete examines. Observation Dans les analyses preliminaires, on observe une correlation entre l’adiponectine de haut poids moleculaire et le metabolisme des glucides seulement chez les femmes atteintes de mucoviscidose. Conclusion CES donnees suggerent que les niveaux d’adiponectine totale et de haut poids moleculaire pourraient etre regulees differemment selon les sexes.