The growing number of patients on premixed long-acting insulin formulations are at increased risk of hyperglycaemia while in hospital, indicating the need for specific management guidelines, researchers say.

Identified in an analysis of Australian hospital data, the issue is likely related to the less frequent dosing of IDegAsp (Ryzodeg 70/30), according to the team.

Their retrospective study included 88 inpatients with type 2 diabetes on IDegAsp prior to and during hospitalisation at the Royal Melbourne and Northern hospitals in Melbourne, along with an equal number of HbA1c-matched individuals on biphasic insulin aspart (BIAsp30).

This latter was chosen as the comparator because it was a commonly used formulation containing the same rapid-acting insulin and ratio (30%) as that of IDegAsp.

Findings were that patient characteristics were well matched, including insulin dose at admission, although the IDegAsp group had less frequent twice-daily insulin dosing than the BIAsp30 group (49% vs 87%).

Both groups had roughly the same number of patient days with blood glucose (BG) below 4 mmol/L, measured using networked BG meter systems, the researchers reported in the Internal Medicine Journal (link here).

However, the patients taking IDegAsp had a significantly higher mean BG per day (10.4 vs 10.0) and the group had a higher proportion of patient-days with a mean BG above 10 mmol/L (48% vs 38%).

Notably, hyperglycaemia in IDegAsp-treated inpatients occurred mostly during the time period of 4pm to midnight, with the group recording an average glucose level of 11.6 in this time period, compared with 10.9 in the BIAsp30 group.

On the other hand, glucose levels were the same between the groups at other times during the day and night, reflecting inadequate control of prandial hyperglycaemia in the late afternoon and evening, according to the authors.

“Our findings imply that more prandial and/or supplemental insulin may be required to control hyperglycaemia in those treated with IDegAsp,” they wrote.

“Since IDegAsp is commonly used in Australia and as it becomes more widely available globally, development of guidelines and evaluation of outcomes will be required to optimise the use of this insulin in hospital.”

The researchers pointed to dosing regimens as the likely culprit, arguing that the typical once daily administration of IDegAsp (often administered in the morning) “may be insufficient to counteract postprandial or counterregulatory response-related hyperglycaemia”.

“In contrast individuals treated with BIAsp30 mostly received twice daily administration, hence may be more effective at counteracting postprandial hyperglycaemia,” they said.

The fact that mean glucose were similar between the groups overnight, when most inpatients were not eating, suggested the intermediate or basal components of both insulins were comparable in efficacy, the authors added.

“The clinical implication is that more prandial or supplemental insulin may be required to prevent hyperglycaemia in individuals who are treated with IDegAsp during their hospital stay,” they wrote.