[Value of continuous glucose monitoring in screening for diabetes in cystic fibrosis
ABSTRACT In the past few years, survival has increased for people with cystic fibrosis (CF). Diabetes is an important complication of CF caused by pancreatic insufficiency, which reduces insulin secretion. Because of increased longevity of patients with CF, the prevalence of CF-related diabetes (CFRD) has increased. CFRD is associated with increased mortality and morbidity. Several studies have reported a decline in nutritional and pulmonary status 2-4 years before the diagnosis of CFRD. The introduction of insulin treatment can produce clinical improvement in weight and lung function. The oral glucose tolerance test is currently the reference method in screening for CFRD, but the current definition of diabetes based on the 2-h post-load plasma glucose level may not be the most accurate method for early detection of glucose tolerance abnormalities in CF. The continuous glucose monitoring system (CGMS) has been described as a useful tool for early detection of hyperglycemia in the CF patient. We tested the CGMS in CF patients with unexplained alteration of their general status. The aim of this study was to assess the value of the CGMS in this population.
An annual OGTT (following World Health Organization recommendations) was conducted as a screening test to identify CFRD in patients aged over 10 years or patients aged under 10 years with a poorer clinical status. The CGMS was performed in patients with unexplained worsened clinical status and without diabetes in OGTT.
Forty-two patients aged from 8.5 to 19 years were screened using OGTT for CFRD. According to ADA criteria, 23 patients (54.8%) displayed normal glucose tolerance, 14 (33.3%) impaired glucose tolerance, and 5 diabetes (11.9%). Out of 37 nondiabetic, the CGMS was used in 20 patients with unexplained altered general status. The CGMS revealed peaks of glucose values greater than 2 g/L in 16 patients, 9 patients with normal glucose tolerance, and 7 patients with impaired glucose tolerance. The mean CGMS glucose and time of glycemic monitoring above 1.4 g/L increased in patients with peaks greater than 2 g/L compared to patients without peaks (p=0.0016 and p=0.0069 respectively). After analysis of the CGMS, the prevalence of diabetes increased from 11.9 to 50%. Three patients aged less than 10 years with a normal OGTT profile presented glycemic peaks greater than 2 g/L during CGMS.
CGMS revealed more glucose metabolism abnormalities than OGTT in patients with unexplained altered general status.
- SourceAvailable from: Ashraf T Soliman
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- "These glucose concentrations (by CGMS and glucometer) were downloaded after 3 days and interpreted using Medtronic software. The diagnosis of glycemia status whether normal, diabetic, IFG, IGT was done according to American diabetes association criteria. As plasma, serum and IF glucose levels exhibit high correlations and in the absence of published criteria for diagnosing glycemic abnormalities by CGMS, the same criteria were applied for both the OGTT results as well as the CGMS data. "
ABSTRACT: Both insulin deficiency and resistance are reported in patients with β-thalassemia major (BTM). The use of continuous blood glucose monitoring (CGM), among the different methods for early detection of glycemic abnormalities, has not been studied thoroughly in these adolescents. To assess the oralglucose tolerance (OGT) and 72-h continuous glucose concentration by the continuous glucose monitoring system (CGMS) and calculate homeostatic model assessment (HOMA), and the quantitative insulin sensitivity check index (QUICKI) was conducted in 16 adolescents with BTM who were receiving regular blood transfusions every 2-4 weeks and iron-chelation therapy since early childhood. SIXTEEN ADOLESCENTS WITH BTM (AGE: 19.75 ± 3 years) were investigated. Using OGTT, (25%) had impaired fasting blood (plasma) glucose concentration (BG) (>5.6 mmol/L). 2-h after the glucose load, one of them had BG = 16.2 mmol/L (diabetic) and two had impaired glucose tolerance (IGT) (BG > 7.8 and <11.1 mmol/L). Monitoring the maximum (postprandial) BG using CGMS,4 adolescents were diagnosed with diabetes (25%) (BG >11.1 mmol/L) and 9 with IGT (56%). HOMA and QUICKI revealed levels <2.6 (1.6 ± 0.8) and >0.33 (0.36 ± 0.03), respectively, ruling out significant insulin resistance in these adolescents. There was a significant negative correlation between the β-cell function (B%) on one hand and the fasting and the 2-h BG (r=-0.6, and - 0.48, P < 0.01, respectively) on the other hand. Neither fasting serum insulin nor c-peptide concentrations were correlated with fasting BG or ferritin levels. The average and maximum blood glucose levels during CGM were significantly correlated with the fasting BG (r = 0.68 and 0.39, respectively, with P < 0.01) and with the BG at 2-hour after oral glucose intake (r = 0.87 and 0.86 respectively, with P < 0.001). Ferritin concentrations were correlated with the fasting BG and the 2-h blood glucose levels in the OGTT (r = 0.52, and r = 0.43, respectively, P < 0.01) as well as with the average BG recorded by CGM (r = 0.75, P < 0.01). CGM has proven to be superior to OGTT for the diagnosis of glycemic abnormalities in adolescents with BTM. Defective β-cell function rather than insulin resistance appeared to be the cause for these abnormalities.05/2013; 17(3):490-5. DOI:10.4103/2230-8210.111647
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ABSTRACT: BACKGROUND Cystic fibrosis (CF) is an autosomal recessive disease caused by a CF trans-membrane regulator (CFTR) defect. Its prevalence is 1:2500 in Caucasians, 1:15300 among African Americans and is rare in Southeast Asia. The present study aims to review demographic data, clinical manifestations and laboratory findings of Iranian children diagnosed with CF who referred to a Children's Hospital Medical Center in Tehran, Iran during a ten-year period. METHODS In a retrospective study from 1991-2000, all hospitalized patients with documented CF were reviewed. Diagnosis was based on clinical findings and sweat chloride levels above 60 mEq/L. RESULTS A total of 233 patients [females: 91 (39.1%), males: 142 (60.9%)] were enrolled. The onset of symptoms was before the first month of life in 12.1%, between 1-6 months of age in 75.1%, and between 6-12 months of age in 6.9% of patients. Consanguinity of parents was present in 42.5% of patients. Respiratory (81.5%) and gastrointestinal (73.4%) symptoms, in addition to growth retardation were the most common presentations Eighty-eight percent of patients weighted below the fifth percentile. Of the 207 chest radiographs performed, the most frequent finding was hyper-aeration associated with pneumonia. Among 138 patients in whom barium swallows were performed, 102 (74%) had gastroesophageal reflux. A total of 27 patients expired, mostly from respiratory failure (96.3%). CONCLUSION CF is not a rare disease in Iran. We suggest early diagnosis and appropriate maintenance therapy for improving morbidity and mortality amongst CF patients.Middle East journal of digestive diseases 01/2010; 2(1):20-3.
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ABSTRACT: Glycemic abnormalities in Adolescents with thalassemia detected by CGMS versus OGTT