Full The Relationship between Continuous Glucose Monitoring and OGTT in Youth and Young Adults with Cystic Fibrosis

Author(s):  
Christine L Chan ◽  
Laura Pyle ◽  
Tim Vigers ◽  
Philip S Zeitler ◽  
Kristen J Nadeau

Abstract Context Early glucose abnormalities in people with CF (PwCF) are commonly detected by continuous glucose monitoring (CGM). Relationships between these CGM abnormalities and oral glucose tolerance testing (OGTT) in PwCF have not been fully characterized. Objective(s) 1) To determine the relationship between CGM and common OGTT-derived estimates of β-cell function, including C-peptide index and oral disposition index (oDI) and 2) to explore whether CGM can be used to screen for OGTT-defined prediabetes and cystic fibrosis related diabetes (CFRD). Study Design/Methods PwCF not on insulin and healthy controls ages 6-25 yrs were enrolled in a prospective study collecting OGTT and CGM. A subset underwent frequently-sampled OGTTs (fsOGTT) with 7-point glucose, insulin, and C-peptide measurements. Pearson’s correlation coefficient was used to test the association between select CGM and fsOGTT measures. ROC analysis was applied to CGM variables to determine the cutoff optimizing sensitivity and specificity for detecting prediabetes and CFRD. Results A total of 120 participants (controls=35, CF=85), including 69 with fsOGTTs, were included. CGM coefficient of variation correlated inversely with C-peptide index (Cpeptide30-Cpeptide0/Glucose30-Glucose0) (r=-0.45, p<0.001) and oDIcpeptide (C-peptide index)(1/cpep0) (r=-0.48, p<0.0001). In PwCF, CGM variables had ROC-AUCs ranging from 0.43-0.57 for prediabetes and 0.47-0.6 for CFRD. Conclusions Greater glycemic variability on CGM correlated with reduced β-cell function. However, CGM performed poorly at discriminating individuals with and without OGTT-defined CFRD and prediabetes. Prospective studies are now needed to determine how well the different tests predict clinically-relevant non-glycemic outcomes in PwCF.

2007 ◽  
Vol 292 (6) ◽  
pp. E1575-E1580 ◽  
Author(s):  
Shinji Sakaue ◽  
Shinji Ishimaru ◽  
Daisuke Ikeda ◽  
Yoshinori Ohtsuka ◽  
Toshiro Honda ◽  
...  

Although a hyperbolic relationship between insulin secretion and insulin sensitivity has been shown, the relationship has been often questioned. We examined the relationship using oral glucose tolerance test (OGTT)-derived indexes. A total of 374 Japanese subjects who had never been given a diagnosis of diabetes underwent a 75-g OGTT. In subjects with normal glucose tolerance (NGT), the ln [insulinogenic index (IGI)] was described by a linear function of ln ( x) ( x, insulin sensitivity index) in regression analysis when the reciprocal of the insulin resistance index in homeostasis model assessment, Matsuda's index, and oral glucose insulin sensitivity index were used as x. Because the 95% confidence interval of the slope of the regression line did not necessarily include −1, the relationships between IGI and x were not always hyperbolic, but power functions IGI × xα = a constant. We thought that IGI × xα was an appropriate β-cell function estimate adjusted by insulin sensitivity and referred to it as β-cell function index (BI). When Matsuda's index was employed as x, the BI values were decreased in subjects without NGT. Log BI had a better correlation with fasting plasma glucose (PG; FPG) and 2-h PG in non-NGT subjects than in NGT subjects. In subjects with any glucose tolerance, log BI was linearly correlated with 1-h PG and glucose spike (the difference between maximum PG and FPG). In conclusion, the relationship between insulin secretion and insulin sensitivity was not always hyperbolic. The BI is a useful tool in the estimation of β-cell function with a mathematical basis.


Author(s):  
Kevin J Scully ◽  
Jordan S Sherwood ◽  
Kimberly Martin ◽  
Melanie Ruazol ◽  
Peter Marchetti ◽  
...  

Abstract Context The clinical utility and implications of continuous glucose monitoring (CGM) in cystic fibrosis (CF) are unclear. Objective We examined the correlation between CGM measures and clinical outcomes in adults with CF, investigated the relationship between hemoglobin A1c (HbA1c) and CGM-derived average glucose (AG), and explored CGM measures that distinguish CFRD from normal and abnormal glucose tolerance. Design Prospective observational study. Participants 77 adults with CF. Main outcomes CGM and HbA1c measured at 2-3 time-points three months apart. Results Thirty-one of the 77 participants met American Diabetes Association-recommended diagnostic criteria for CFRD by oral glucose tolerance testing and/or HbA1c. In all participants, CGM measures of hyperglycemia and glycemic variability correlated with nutritional status and pulmonary function. HbA1c was correlated with AG (R 2=0.71, p=<0.001), with no significant difference between this regression line and that previously established in type 1 and type 2 diabetes and healthy volunteers. Cutoffs of 17.5% time >140 mg/dL and 3.4% time >180 mg/dL had sensitivities of 87% and 90%, respectively, and specificities of 95%, for identifying CFRD. Area under the curve and percent of participants correctly classified with CFRD were higher for AG, standard deviation, % time >140, >180, and >250 mg/dL than HbA1c. Conclusions CGM measures of hyperglycemia and glycemic variability are superior to HbA1c in distinguishing those with and without CFRD. CGM-derived AG is strongly correlated with HbA1c in adults with CF, with a similar relationship to other diabetes populations. Future studies are needed to investigate CGM as a diagnostic and screening tool for CFRD.


Author(s):  
Katerina Theocharous ◽  
Bernadette Prentice ◽  
Charles F. Verge ◽  
Adam Jaffé ◽  
Shihab Hameed

With advances in technology, it is now possible to detect the emergence of glucose abnormalities in cystic fibrosis with improved sensitivity, and from a very early age. These abnormalities are increasingly recognized as predictors of clinical decline, raising the possibility that early intervention may slow or prevent this deterioration. In this chapter, we will review the available literature on methods of detecting glucose abnormalities in cystic fibrosis (random and fasting glucose, HbA1c, oral glucose tolerance testing, and continuous glucose monitoring), and detail their advantages and possible limitations in the interpretation of glycemic data. We will also discuss treatment outcomes of early intervention, prior to the diagnosis of diabetes as currently defined.


2011 ◽  
Vol 300 (4) ◽  
pp. R941-R948 ◽  
Author(s):  
Andrea Tura ◽  
Umberto Morbiducci ◽  
Stefano Sbrignadello ◽  
Yvonne Winhofer ◽  
Giovanni Pacini ◽  
...  

We aimed to analyze the shape of the glucose, insulin, and C-peptide curves during a 3-h oral glucose tolerance test (OGTT). Another aim was defining an index of shape taking into account the whole OGTT pattern. Five-hundred ninety-two OGTT curves were analyzed, mainly from women with former gestational diabetes, with glycemic concentrations characterized by normal glucose tolerance ( n = 411), impaired glucose metabolism ( n = 134), and Type 2 diabetes ( n = 47). Glucose curves were classified according to their shape (monophasic, biphasic, triphasic, and 4/5-phases), and the metabolic condition of the subjects, divided according to the glucose shape stratification, was analyzed. Indices of shape based on the discrete second-order derivative of the curve patterns were also defined. We found that the majority of the glucose curves were monophasic ( n = 262). Complex shapes were less frequent but not rare ( n = 37 for the 4/5-phases shape, i.e., three peaks). There was a tendency toward the amelioration of the metabolic condition for increasing complexity of the shape, as indicated by lower glucose concentrations, improved insulin sensitivity and β-cell function. The shape index computed on C-peptide, WHOSHCP (WHole-Ogtt-SHape-index–C-peptide), showed a progressive increase [monophasic: 0.93 ± 0.04 (dimensionless); 4/5-phases: 1.35 ± 0.14], and it showed properties typical of β-cell function indices. We also found that the type of glucose shape is often associated to similar insulin and C-peptide shape. In conclusion, OGTT curves can be characterized by high variability, and complex OGTT shape is associated with better glucose tolerance. WHOSHCP (WHole-Ogtt-SHape-index) may be a powerful index of β-cell function much simpler than model-based indices.


2008 ◽  
Vol 93 (6) ◽  
pp. 2115-2121 ◽  
Author(s):  
Taro Maruyama ◽  
Shoichiro Tanaka ◽  
Akira Shimada ◽  
Osamu Funae ◽  
Akira Kasuga ◽  
...  

Abstract Objective: We tested the hypothesis that insulin therapy rather than sulfonylurea (SU) treatment is preferable to reverse or preserve β-cell function among patients with slowly progressive insulin-dependent (type 1) diabetes (SPIDDM) or latent autoimmune diabetes in adults. Methods: This multicenter, randomized, nonblinded clinical study screened 4089 non-insulin-dependent diabetic patients for glutamic acid decarboxylase autoantibodies (GADAb). Sixty GADAb-positive non-insulin-requiring diabetic patients with a 5-yr duration or shorter of diabetes were assigned to either the SU group (n = 30) or the insulin group (n = 30). Serum C-peptide responses to annual oral glucose tolerance tests were followed up for a mean of 57 months. The primary endpoint was an insulin-dependent state defined by the sum of serum C-peptide values during the oral glucose tolerance test (ΣC-peptide) less than 4 ng/ml (1.32 nmol/liter). Results: The progression rate to an insulin-dependent state in the insulin group (three of 30, 10%) was lower than that in the SU group (13 of 30, 43%; P = 0.003, log-rank). Longitudinal analysis demonstrated that ΣC-peptide values were better preserved in the insulin group than in the SU group. Multiple regression analysis demonstrated that insulin treatment, a preserved C-peptide response, and a low GADAb titer at entry were independent factors in preventing progression to an insulin-dependent state. Subgroup analysis suggested that insulin intervention was highly effective for SPIDDM patients with high GADAb titers [≥10 U/ml (180 World Health Organization U/ml)] and preserved β-cell function [ΣC-peptide ≥ 10 ng/ml (3.31 nmol/liter)] at entry. No severe hypoglycemic episodes occurred during the study. Conclusions: Insulin intervention to preserve β-cell function is effective and safe for patients with SPIDDM or latent autoimmune diabetes in adults.


2017 ◽  
Vol 2 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Lisa R Letourneau ◽  
David Carmody ◽  
Louis H Philipson ◽  
Siri Atma W Greeley

Abstract Although mutations in the proinsulin gene (INS) are the second most common cause of neonatal diabetes mellitus, the natural history of β-cell death and the most appropriate treatments remains unknown. We describe the management and outcome of two sisters with INS-mediated diabetes (S1 and S2) and suggest that more intensive insulin treatment of S2 may have resulted in better clinical outcomes. S1 was diagnosed with diabetes after presenting with serum glucose of 404 mg/dL (22.4 mmol/L) and started multiple daily insulin injections at age 4 months, followed by continuous subcutaneous insulin infusion (CSII) at age 42 months. S1 had positive genetic testing at age 4 months for the GlyB8Ser or Gly32Ser mutation in proinsulin. S2 had positive research-based genetic testing, age 1 month, before she had consistently elevated blood glucose levels. Continuous glucose monitoring revealed abnormal excursions to 200 mg/dL. Low-dose insulin therapy was initiated at age 2.5 months via CSII. At age-matched time points, S2 had higher C-peptide levels, lower hemoglobin A1c values, and lower estimated doses of insulin as compared with S1. Earlier, more intensive insulin treatment was associated with higher C-peptide levels, decreased insulin dosing, and improved glycemic control. Initiating exogenous insulin before overt hyperglycemia and maintaining intensive insulin management may reduce the demand for endogenous insulin production and may preserve β-cell function. Studies accumulating data on greater numbers of participants will be essential to determine whether these associations are consistent for all INS gene mutations.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 752.2-753
Author(s):  
J. C. Quevedo-Abeledo ◽  
F. Genre ◽  
J. Rueda-Gotor ◽  
A. Corrales ◽  
V. Hernández-Hernández ◽  
...  

Background:Insulin resistance (IR) is a state in which a given concentration of insulin is associated with a subnormal glucose response. IR constitutes a major underlying abnormality driving cardiovascular disease in the general population and has been linked to inflammatory diseases. In this sense, several reports have confirmed that inflammation worsens IR and impairs pancreatic β-cell function in inflammatory diseases such as rheumatoid arthritis and systemic lupus erythematosus.Objectives:In this study we aimed to determine the prevalence of IR in patients with spondyloarthritis (SpA) compared to controls, and whether IR can be explained by disease-related features in SpA patients.Methods:Study of 577 subjects, 306 patients diagnosed with SpA according to ASAS criteria and 271 controls. Insulin and C-peptide serum levels, IR and β-cell function (%B) indexes by homeostatic model assessment (HOMA2), and lipid profiles were assessed in patients and controls. A multivariate regression analysis was performed to evaluate the differences in IR indexes between patients and controls and to determine how IR is associated with disease-related characteristics.Results:SpA patients showed higher serum levels of insulin (8.7 [4.8-15.9] vs. 8.0 [5.7-11.2] uU/ml, p=0.001) and C peptide (1.4 [0.7-2.5] vs. 1.2 [0.7-1.7] ng/ml, p=0.000) than controls in the univariate analysis. Similarly, HOMA2-B% and IR were all significantly higher in SpA patients. These differences were still evident when the comparisons were made after the multivariate analysis had been adjusted for traditional IR-related factors (sex, age, BMI, hypertension, dyslipidemia, smoking and, cholesterol), glucocorticoids intake, insulin and C-peptide. Moreover, HOMA2-B% and HOMA2-IR scores, both calculated with insulin or C-peptide, yielded statistically higher significant values in SpA patients than controls.Classic IR-related factors (age, BMI, waist circumference, hypertension, obesity, dyslipidemia, atherogenic index, and triglycerides), as well as CRP serum levels, were all related, to a greater or lesser degree, with IR and β-cell function. Regarding disease-related data, ASDAS-CRP, BASFI and BASMI scores were positively associated with IR; and BASMI and BASDAI scores were positively related to HOMA2-%B-C peptide. Moreover, the use of NSAID and prednisone were, respectively, positive and negatively related to β-cell function. However, only some of the associations of the univariate analysis were maintained after adjusting for confounders. In this sense, disease duration (beta coefficient 2 [95% CI 1-3], p=0.001) and positivity for HLA-B27 (beta coefficient 30 [95% CI 12-49], p=0.002) were associated with higher β-cell functionality after the multivariate analysis.Conclusion:Patients with SpA have an increased IR compared to controls. SpA disease-related data like disease duration and HLA-B27 are independently associated with β-cell dysfunction.Disclosure of Interests:Juan Carlos Quevedo-Abeledo Speakers bureau: Abbvie, Fernanda Genre: None declared, Javier Rueda-Gotor: None declared, Alfonso Corrales Speakers bureau: Abbvie, Vanessa Hernández-Hernández Speakers bureau: Pfizer, Abbvie, MSD, Natalia Fañanas-Rodríguez: None declared, Bernardo Lavín-Gómez: None declared, delgado frias esmeralda Speakers bureau: Pfizer, Abbvie, MSD, Antonia de Vera-González: None declared, Alejandra Delgado-González: None declared, Laura de Armas-Rillo: None declared, Maria Teresa García-Unzueta: None declared, Miguel A González-Gay Grant/research support from: Pfizer, Abbvie, MSD, Speakers bureau: Pfizer, Abbvie, MSD, Iván Ferraz-Amaro Grant/research support from: Pfizer, Abbvie, Speakers bureau: Pfizer, Abbvie, MSD.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Anne Julie Overgaard ◽  
Jens Otto Broby Madsen ◽  
Flemming Pociot ◽  
Jesper Johannesen ◽  
Joachim Størling

Abstract Background Type 1 diabetes (T1D) is caused by immune-mediated destruction of the β-cells. After initiation of insulin therapy many patients experience a period of improved residual β-cell function leading to partial disease remission. Cytokines are important immune-modulatory molecules and contribute to β-cell damage in T1D. The patterns of systemic circulating cytokines during T1D remission are not clear but may constitute biomarkers of disease status and progression. In this study, we investigated if the plasma levels of various pro- and anti-inflammatory cytokines around time of diagnosis were predictors of remission and residual β-cell function in children with T1D followed for one year after disease onset. Methods In a cohort of 63 newly diagnosed children (33% females) with T1D with a mean age of 11.3 years (3.3–17.7), ten cytokines were measured of which eight were detectable in plasma samples by Mesoscale Discovery multiplex technology at study start and after 6 and 12 months. Linear regression models were used to evaluate association of cytokines with stimulated C-peptide. Results Systemic levels of tumor necrosis factor (TNF)-α, interleukin (IL)-2 and IL-6 inversely correlated with stimulated C-peptide levels over the entire study (P < 0.05). The concentrations of TNFα and IL-10 at study start predicted stimulated C-peptide level at 6 months (P = 0.011 and P = 0.043, respectively, adjusted for sex, age, HbA1c and stage of puberty). Conclusions In recent-onset T1D, systemic cytokine levels, and in particular that of TNFα, correlate with residual β-cell function and may serve as prognostic biomarkers of disease remission and progression to optimize treatment strategies. Trial Registration The study was performed according to the criteria of the Helsinki II Declaration and was approved by the Danish Capital Region Ethics Committee on Biomedical Research Ethics (journal number H-3-2014-052). The parents of all participants gave written consent.


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