Incidence of Nocturnal Hypoglycaemia in Insulin-dependent Diabetic Patients on Intensive Therapy

Abstract

The frequency of nocturnal hypoglycaemia, i.e. blood glucose concentration (BG) <3.0 mmol/l, was evaluated in consecutively selected insulin-dependent patients on multiple insulin injections (MII), n = 23, or continuous subcutaneous insulin infusions (CSII), n = 25. Blood was sampled hourly from 23.00 to 07.00. Seven patients (30%) on MII had at least one BG <3.0 mmol/l during the night. Eleven patients (44%) on CSII had hypoglycaemia (NS). The total number of BGs < 3.0 mmol/l was higher on CSII, 42 of 225, versus 16 of 207 on MII (p < 0.025). The duration of hypoglycaemia was 2 hours (range 1-6) on MII and 4 hours (range 1-7) on CSII with a maximal prevalence at 4 hours and between 5 and 7 hours, respectively (p = <0.05). The frequency of nocturnal hypoglycaemia is high in patients on intensified insulin regimens. Nocturnal hypoglycaemia occurs later in the night and is of longer duration on CSII than on MII. HbAlc, BG before bedtime and in the morning might be useful in the evaluation of nocturnal hypoglycaemia.