Hypoglycaemia in Clinical Diabetes

CONCLUSIONS 165Box 7.5 Treatment strategies for patients with impaired awareness ofhypoglycaemia• Frequent blood glucose monitoring (including nocturnal measurements).• Avoid blood glucose values < 40 mmol/l.• Set target range of blood glucose higher than for ‘aware’ patients (e.g. preprandialbetween 6.0–12.0 mmol/l; bedtime > 80 mmol/l)• Avoid HbA 1c in non-diabetic range.• Use predominantly short-acting insulins (e.g. basal-bolus regimen; insulinanalogues).• Regular snacks between meals and at bedtime, containing unrefined carbohydrate.• Appropriate additional carbohydrate consumption and/or insulin dose adjustmentfor premeditated exercise.• Learn to identify subtle neuroglycopenic cues to low blood glucose.low blood glucose during the night. Blood glucose awareness training has been developedin the USA, with re-education of affected patients to recognise neuroglycopenic cues (Coxet al., 1995), but this also requires facilities and resources that are not available in mostcentres. Intensive insulin therapy is contraindicated in patients who have impaired awarenessof hypoglycaemia and treatment goals have to be considered individually. The avoidanceof severe hypoglycaemia is paramount as this may exacerbate the problem, and the use ofmostly short-acting insulin (and possibly insulin analogues) in basal-bolus regimens maybe particularly useful in avoiding biochemical and symptomatic hypoglycaemia withoutcompromising overall glycaemic control.CONCLUSIONS• An inadequate symptomatic warning to hypoglycaemia is common in people withinsulin-treated diabetes and is described as impaired awareness of hypoglycaemia orhypoglycaemia unawareness. It increases in prevalence with duration of insulin-treateddiabetes.• In people who report impaired awareness of hypoglycaemia, asymptomatic hypoglycaemiaoccurs more frequently during routine blood glucose monitoring. This may alert theclinician to the possibility that an individual is developing this problem.• Impaired awareness of hypoglycaemia may be associated with strict glycaemic control;significant modification of the symptomatic response occurs when the HbA 1c concentrationis within the non-diabetic range.