Diabetes Care

Variation of postprandial plasma glucose, palatability, and symptoms associated with a standardized mixed test meal versus 75 g oral glucose.

Year 1998
Wolever TM. Chiasson JL. Csima A. Hunt JA. Palmason C. Ross SA. Ryan EA.
Department of Nutritional Sciences, Univeristy of Toronto, Ontario, Canada. thomas.wolever@utoronto.ca
OBJECTIVE: To compare within-subject variability of plasma glucose measured 2 h after a glucose tolerance test (GTT) with that of plasma glucose measured 2 h after administration of a standardized test meal (diabetes screening product [DSP], Ceapro, Edmonton, Alberta, Canada) and to determine the relationship between the two sets of plasma glucose measurements. RESEARCH DESIGN AND METHODS: Plasma glucose and insulin responses of 36 overnight-fasted subjects (10 lean normal, 9 obese normal, 9 with impaired glucose tolerance [IGT], and 8 with mild diabetes) were studied on eight different mornings after they consumed 75 g oral glucose or 50 g carbohydrate from the DSP. Each test meal was repeated four times by each subject. Within-subject coefficients of variation (CVs) (CV = 100 x SD/mean) of plasma glucose concentrations 2 h after administration of the GTT and DSP were compared by repeated measures ANOVA and linear regression analysis. RESULTS: Mean plasma glucose 2 h after administration of the DSP (D) was linearly related to that 2 h after the GTT (G): G = 1.5 x D - 1.6 (r = 0.97, P < 0.0001). The CV of 2-h plasma glucose was significantly lower after administration of the DSP, 10.5 +/- 1.0%, than after the GTT, 12.7 +/- 1.18% (P = 0.025). The effect of test meal on CV differed in different groups of subjects (P = 0.018), with the largest difference found in IGT subjects, in whom the CV after DSP administration was 47% less than after the GTT (P = 0.0005). The DSP was significantly more palatable and produced fewer adverse symptoms than the GTT. CONCLUSIONS: Plasma glucose concentrations measured 2 h after DSP administration are closely related to those measured 2 h after the GTT but are more consistent than the 2-h post-GTT concentrations within the critical IGT range. This finding suggests that measurement of plasma glucose 2 h after administration of the DSP may allow more precise discrimination among normal glucose levels, IGT, and diabetes than measurement of plasma glucose 2 h after the GTT.

Identification and treatment of cystic fibrosis-related diabetes. A survey of current medical practice in the U.S.

Year 1998
Allen HF. Gay EC. Klingensmith GJ. Hamman RF.
Department of Pediatrics, Tufts University School of Medicine, Boston, Massachusetts, USA. allenh@bmcnorth.bhs.org
OBJECTIVE: To describe physicians' attitudes and practices in screening for and treating abnormalities in glucose homeostasis in cystic fibrosis (CF) patients and to test the hypotheses that guidelines for screening for CF-related diabetes (CFRD) are not followed at most centers and that screening and treatment vary by the care provider's background. RESEARCH DESIGN AND METHODS: This cross-sectional survey included three groups of physicians: 1) 593 members of the Lawson Wilkins Pediatric Endocrine Society (LWPES), 2) 462 members of the pediatric assembly of the American Thoracic Society (ATS), and 3) 194 directors of cystic fibrosis centers (CFD). A mailed questionnaire was used for the survey. RESULTS: The overall response rate was 67%. Of these, 224 LWPES, 143 ATS, and 135 CFD physicians reported actively seeing CF patients. About two-thirds of CF physicians (ATS and CFD) reported routine screening for impaired glucose tolerance (IGT) in asymptomatic CF patients; a random glucose is most often used (60%), followed by HbA1c (50%), urine glucose (44%), fasting glucose (21%), and oral glucose tolerance test (2%). Only 40% of LWPES physicians reported intervening for stress-induced hyperglycemia, but 61% reported use of insulin for persistent IGT. Management of CFRD was similar for all groups; most physicians used insulin (91%). LWPES recommended more intensive glucose testing and nutritional guidelines than did ATS/CFD (P < 0.0001). LWPES reported less concern about risks of diabetes complications (P < 0.0001) and the importance of minimizing burdensome interventions (P < 0.01). All groups considered weight management a top priority. CONCLUSIONS: Screening for IGT is not routinely done in CF patients and screening tests vary. Greater agreement exists on methods of treating patients with persistent IGT or CFRD, although goals and aggressiveness of treatment vary with the provider's background. A consensus conference is recommended.