Although the scientific literature contains numerous reports of the statistical accuracy of systems for self-monitoring of blood glucose (SMBG), most of these studies determine accuracy in ways that may not be clinically useful. We have developed an error grid analysis (EGA), which describes the clinical accuracy of SMBG systems over the entire range of blood glucose values, taking into account 1) the absolute value of the system-generated glucose value, 2) the absolute value of the reference blood glucose value, 3) the relative difference between these two values, and 4) the clinical significance of this difference. The EGA of accuracy of five different reflectance meters (Eyetone, Dextrometer, Glucometer I, Glucometer II, Memory Glucometer II), a visually interpretable glucose reagent strip (Glucostix), and filter-paper spot glucose determinations is presented. In addition, reanalyses of a laboratory comparison of three reflectance meters (Accucheck II, Glucometer II, Glucoscan 9000) and of two previously published studies comparing the accuracy of five different reflectance meters with EGA is described. EGA provides the practitioner and the researcher with a clinically meaningful method for evaluating the accuracy of blood glucose values generated with various monitoring systems and for analyzing the clinical implications of previously published data.

Type I (insulin-dependent) diabetic individuals and health professionals often assume that the symptoms of extremely low or high blood glucose (BG) levels can be recognized and, consequently, appropriate treatment decisions can be based on symptom perception. Because no research has documented the validity of these assumptions, this study tested the ability to perceive BG concentration. Nineteen type I adults, experienced in self-monitoring of BG (SMBG), estimated their BG 40-54 times just before measurement of actual BG. This procedure was repeated under two conditions: (1) in the hospital (hospital condition) while connected to an insulin/glucose infusion system that artificially manipulated BG, leaving subjects only symptomatic, or internal, cues and (2) in the natural environment (home condition), where both internal and external cues, e.g., food and insulin consumption, were available. Estimates significantly correlated with actual BG for 7 of 16 subjects in the hospital condition and for 18 of 19 subjects in the home condition. Believed ability to estimate BG did not predict documented ability in either condition. An evaluation of the treatment significance of estimation errors showed that the majority of errors were relatively benign. The most common error affecting clinical outcome was estimated euglycemia when actual BG was hypoglycemic or hyperglycemic.

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The plasma membrane of hepatic parenchymal cells contains an adenyl cyclase system that is stimulated by glucagon. Adrenocorticotropin and epinephrine do not stimulate this adenyl cyclase, and very little cyclic phospho-diesterase activity is present in the membrane. These findings support the concept that glucagon exerts its regulatory action in the liver by stimulating adenyl cyclase activity in the plasma membrane.

The ability of psyllium fiber to reduce postprandial serum glucose and insulin concentrations was studied in 18 non-insulin-dependent diabetic patients in a crossover design. Psyllium fiber or placebo was administered twice during each 15-h crossover phase, immediately before breakfast and dinner. No psyllium fiber or placebo was given at lunch, which allowed measurement of residual or second-meal effects. For meals eaten immediately after psyllium ingestion, maximum postprandial glucose elevation was reduced by 14% at breakfast and 20% at dinner relative to placebo. Postprandial serum insulin concentrations measured after breakfast were reduced by 12% relative to placebo. Second-meal effects after lunch showed a 31% reduction in postprandial glucose elevation relative to placebo. No significant differences in effects were noted between patients whose diabetes was controlled by diet alone and those whose diabetes was controlled by oral hypoglycemic drugs. Results indicate that psyllium as a meal supplement reduces proximate and second-meal postprandial glucose and insulin concentrations in non-insulin-dependent diabetics.