Comparison of Insulin Detemir and NPH With Respect to Lowering the Blood Sugar and Symptoms Experienced by Type 1 Diabetics During Hypoglycaemia

Inclusion Criteria: * Signed and dated informed consent obtained before any trial-related activities. * Type 1 diabetes * Treatment with insulin for minimum three months * Duration of diabetes for more than 12 months * Body Mass Index (BMI) less than 30 kg/m2 * HbA1c equal to or greater than 10 % based on analysis from central laboratory Exclusion Criteria: * Participation in any other clinical trial involving other investigational products within the last three months * Current treatment with insulin in a daily dose above 100 U * Episode of symptomatic hypoglycaemia, or a capillary plasma glucose value of less than 3.5 mmol/L in the past two weeks * Hypoglycaemic unawareness or severe autonomic neuropathy * Current treatment with drugs known to interfere with glucose metabolism such as systemic corticosteroids, non-selective beta-blockers and MAO inhibitors * Current treatment with oral antidiabetic drugs * Impaired hepatic function measured as ALAT of more than two times the upper reference limit * Impaired renal function measured as creatinine of more than 150 micromol/L (1.7 mg/dL) * Cardiac problems defined as decompensated heart failure (NYHA class III and IV) at any time and/or angina pectoris and/or myocardial infarction within the last 12 months * Known or suspected allergy to trial product or related products * Mental incapacity, unwillingness or language barriers precluding adequate understanding or co-operation * Blood donation of more than 500 mL within the last three months * Any condition that the Investigator and/or the Sponsor feels would interfere with study participation or evaluation of results * Pregnancy or intention of becoming pregnant, breast-feeding or judged to be using inadequate contraceptive methods. Adequate contraceptive methods are sterilisation, intrauterine device (IUD), oral contraceptives or consistent use of barrier methods * Previous participation in this trial