Marta Alves, Celestino Neves, Ana Varela, Cristina Arteiro, Luís Miguel Pereira, Davide Carvalho, José Luís Medina. Endocrinology Service, S. João Hospital, Faculty of Medicine, University of Porto, Portugal Endocrinology Service, S. João Hospital, Faculty of Medicine, University of Porto, Portugal 2008 TRANSIENT INTERSTITIAL GLUCOSE MONITORING IMPROVES GLYCAEMIC CONTROL 11th Meeting of the Mediterranean Group for the Study of Diabetes Malta, April 23–26, 2009

Background  Self-monitoring with a blood glucose meter is useful but limited: Patient adherence/nocturnal glycaemia/post-prandial period Patient adherence/nocturnal glycaemia/post-prandial period Isolated glycaemic values Isolated glycaemic values Does not access asymptomatic hypoglycaemias Does not access asymptomatic hypoglycaemias  HbA1c interpretation: Limited in some situations (ex: anaemia, haemolysis, haemoglobin variants, liver disease) Limited in some situations (ex: anaemia, haemolysis, haemoglobin variants, liver disease) Reflexes the mean blood glucose levels Reflexes the mean blood glucose levels Do not able us to correctly interpret the real metabolic control We need a method that enables us to read the “whole story”

Background  The continuous glucose monitoring system (CGMS), detects fluctuations of glucose levels, informing about direction, magnitude, duration, frequency and its causes, allowing a more realistic perception of glycaemic control.

Continuous intersticial glucose monitoring  Glucoday® (A. Menarini Diagnostics) is na intersticial glucose monitoring device which allows the knowledgment of continuous intersticial glucose concentrations in the subcutaneous tissue.  It uses microdyalisis technique to access intersticial glucose concentration.  Reading of results: each second (record of the mean value each 3 minutes)  Reading limits: mg/dL

Continuous intersticial glucose monitorization  This system was validated in several studies. It was shown a good correlation between intersticial and blood glucose levels.  Boland EA, et al. Diabetes Care 24:1858–1862,  5 - Gross TM, et al. Diabetes Technol Ther 2:49 – 56,  Chee W, et al. Endocrinol Metab Clin N Am 33: ,  Jeha GS, et al. Diabetes Care 27: , 2004.

Objectives  To evaluate GlucoDay potentialities in clinical practice.  To access monitoring parameters of glycaemic control.  To compare A1c values before and after knowledgement of the results and consequent institution of adjusted therapeutical measures.

Patients and methods  The continuous glucose monitoring with the GlucoDay® system, of the A. Menarini Diagnostics was performed in 53 type 1 diabetic patients with: Bad glucose control Bad glucose control Nocturnal/asymptomatic hypoglycaemias Nocturnal/asymptomatic hypoglycaemias Age (years) (mean±SD) 37,7±12,3 Men (n/%) 19 (35,8) Women (n/%) 34 (64,2) Diabetes duration (years) (mean±SD) 15,5±9,5 HbA1c % (mean±SD) 8,6±1,9 (5- 12,9)

Patients and methods  We evaluated: the number of episodes of hypoglycaemia <60 mg/dl (3.3 mmol/L) the number of episodes of hypoglycaemia <60 mg/dl (3.3 mmol/L) The number of episodes of hyperglycaemia (values above 200 mg/dl (11.1mmol/L)) The number of episodes of hyperglycaemia (values above 200 mg/dl (11.1mmol/L)) the percentage of time in hypoglycaemia the percentage of time in hypoglycaemia the percentage of time in hyperglycaemia the percentage of time in hyperglycaemia during the period of monitorization (~ 48 hours) during the period of monitorization (~ 48 hours)

Results Hypoglycaemic episodes: 8,5  9,5 Hyperglycaemic episodes: 14,6  10,3 % of time in hypoglycaemia: 11,3  15 % of time in hyperglycaemia: 35  23,1 n %

Tempo (h) Glucose (mg/dl) Regular 8U Regular 6U NPH 12U Regular 8U Nocturnal hypoglycaemias L.M.C., 35 Anos, DM1 HbA1c=7,4%, Duração 25 Anos

Nocturnal hyperglycaemias

Bad glycaemic control

Persistent hyperglycaemias R.C.P.T., 74 Anos, DM1, Duração 40 Anos, HbA1c 12,4%

Assymptomatic hypoglycaemias P.M.P.L.M., 48 Anos DM1, Duração 20 Anos HbA1c 12,9%

Average A1c before and 4 to 10 months after monitorization  Before: A1c 8,6±1,9% A1c 8,6±1,9%  After: A1c 7,6±1,2% A1c 7,6±1,2% 8,6% 7,6%

Conclusions  Glycaemic profile obtained with CGMS gives us much more information than conventional methods of blood glucose control assessment.  With continuous intersticial glucose monitoring we can know the patient glycaemic profile which allows: better therapeutical approaches, better therapeutical approaches, improvement of metabolic controlimprovement of metabolic control essential for reduction of acute and chronic complications of diabetes. essential for reduction of acute and chronic complications of diabetes.   We believe that TRANSIENT INTERSTITIAL GLUCOSE MONITORING IMPROVES GLYCAEMIC CONTROL