The effect of alcohol on blood glucose in Type 1 diabetes * /metabolic modelling and integration in a decision support system Søren Plougmann a, *, Ole Hejlesen a , Benjamin Turner b , David Kerr b , David Cavan b a Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 7D, 9220 Aalborg, Denmark b Bournemouth Diabetes and Endocrine Centre, Royal Bournemouth Hospital, Bournemouth BH7 7DW, UK Received 20 December 2002; received in revised form 31 March 2003; accepted 2 April 2003 KEYWORDS Alcohol; Blood glucose; Diabetes; DiasNet; Metabolism; Modelling Summary Introduction : We have recently shown, in studies with patients with Type 1 (insulin dependent) diabetes, that alcohol intake at 21:00 h significantly reduced blood glucose values after 10  /12 h, compared with control studies with no alcohol. Hypothesis : We hypothesised that this was due to the following effects of alcohol: (1) alcohol metabolism increases NADH, leading to a reduction in hepatic gluconeogen- esis; (2) increased glycogen phosphorylase activity depletes hepatic glycogen stores; (3) after the alcohol is metabolised, hepatic insulin sensitivity is increased, leading to the restoration of glycogen stores and reduction in blood glucose levels; and (4) consequently, after several hours, glycogen stores and insulin sensitivity return to normal. Results : A model describing these changes (DiasNet-Alcohol) was implemen- ted into the DiasNet model of human glucose metabolism. Our study suggests that the DiasNet-Alcohol model gives a reasonable approximation of these effects of alcohol on blood glucose concentration observed in our study and supports our hypothesis for the mechanism behind these effects in Type 1 diabetes. – 2003 Elsevier Science Ireland Ltd. All rights reserved. 1. Introduction Management of glucose control in patients with Type 1 (insulin dependent) diabetes is an ongoing day-to-day task. The assessment of diet and corresponding insulin therapy is complicated and difficult to formalise, and experience is a key issue. Achieving this experience from real life situations is not easy and includes high risk of hypoglycaemia (inappropriately low blood glucose) and hyperglycaemia (inappropriately high blood glucose). To assist in this process, information technology has been applied in the form of model-based decision support systems. One such system is DiasNet [1], which is used by patients as a tool for education, communication, and decision support. DiasNet is a new, more patient oriented version of a well documented decision support system [2], that has been evaluated in five clinical studies indicating a significant benefit from using the system to give advice on insulin therapy. The *Corresponding author. Tel.:  /45-96-35-8782. E-mail address: spp@hst.auc.dk (S. Plougmann). International Journal of Medical Informatics (2003) 70, 337  /344 www.elsevier.com/locate/ijmedinf 1386-5056/03/$ - see front matter – 2003 Elsevier Science Ireland Ltd. All rights reserved. doi:10.1016/S1386-5056(03)00038-8