Hypoglycaemia induced by exogenous insulin –‘human’ and animal insulin compared

Abstract

Evidence does not support the contention that treatment with 'human' insulin per se affects the frequency, severity or symptoms of hypoglycaemia. However, a number of studies, mainly those of less rigorous design, describe an effect when people are transferred from animal insulin to 'human' insulin. It is not possible to state how common this is or whether the phenomenon is specific to 'human' insulin or an effect resulting from stricter glycaemic control (perhaps compounded, in some cases, by neurological complications in long-standing diabetes). This remaining uncertainty makes it essential that insulin from animal sources continues to be available so that clinicians and patients may retain this choice of treatment.

Comparative effect of human soluble insulin and insulin aspart upon hypoglycaemia‐induced alterations in cardiac repolarization

“…Experimental hypoglycaemia alters ventricular repolarization with prolongation of the QT interval [14], indicating a possible mechanism which might explain the increased risk of sudden overnight deaths in young type 1 diabetic patients [11]. In the early 1990s, it was claimed that these deaths were linked to the use of human insulin [30, 31] , but a recent systematic review found no evidence that HI has a specific effect on the physiological response to hypoglycaemia when compared with insulin of other species [12]. Nevertheless, as a range of medications, including anti‐arrhythmic drugs, antihistamines and antibiotics can prolong cardiac repolarization [32], the controversy surrounding HI highlights the importance of assessing the effect of new insulin analogues on the electrocardiogram.…”

“…Young people with type 1 diabetes may be at risk of sudden death from hypoglycaemia particularly at night (the ‘dead in bed’ syndrome) [11]. The initial suggestion that this was due to the introduction of human insulin has been largely refuted [12] and there is increasing evidence to support an alternative explanation. Insulin‐induced hypoglycaemia causes a fall in potassium that in combination with sympathoadrenal activation leads to abnormalities of cardiac repolarization [13] manifested by lengthening of the QT interval in patients with both type 1 and type 2 diabetes [14].…”

Hypoglycaemia unawareness: a reversible problem?

“…Consideration of their different pharmacodynamic properties will help determine which insulin is most likely to be the culprit at a given time. A recent analysis of the published data found that ‘human’ insulins were no more likely to be associated with increased hypoglycaemia risk or hypoglycaemia unawareness than porcine insulins, with almost equal numbers of structured trials finding more hypoglycaemia or no difference in the porcine arms as finding more hypoglycaemia problems in the ‘human’ arms[21]. However, patient preference is important as individual responses to each insulin type cannot be excluded.…”

What's new in the journals?

“…Consideration of their different pharmacodynamic properties will help determine which insulin is most likely to be the culprit at a given time. A recent analysis of the published data found that`human' insulins were no more likely to be associated with increased hypoglycaemia risk or hypoglycaemia unawareness than porcine insulins, with almost equal numbers of structured trials ®nding more hypoglycaemia or no difference in the porcine arms as ®nding more hypoglycaemia problems in the`human' arms [21]. However, patient preference is important as individual responses to each insulin type cannot be excluded.…”