Effectiveness of premixed insulin to achieve glycaemic control in type 2 diabetes: A retrospective UK cohort study

Aim: To investigate the effectiveness of premixed insulin for achieving glycaemic outcomes in clinical practice in the UK.

Materials and methods: Electronic medical record data from The Health Improvement Network database were captured for adults with type 2 diabetes (T2D) uncontrolled (HbA1c ≥9%) on two or more oral antihyperglycaemic drugs (OADs) initiating premixed insulin. Effectiveness of premixed insulin was assessed by the probability and incidence of achieving glycaemic outcomes (target HbA1c <7.5% [<58 mmol/mol] and a ≥1% or ≥2% HbA1c reduction) over 24 months.

Results: Data from 974 participants (mean age 62 years; 56% male; 52% obese or extremely obese; mean HbA1c 11.3% [100 mmol/mol]; hypertension 64%, dyslipidaemia 23% and nephropathy 21%) were analysed. The probability of achieving HbA1c <7.5% was highest during months 3-6 (18.2%), while the cumulative probability of achieving this target plateaued between months 15-24 (15.7%-16.0%). Incidence of achieving all glycaemic outcomes plateaued after 12 months and differed by baseline HbA1c, but not OAD use. Factors affecting some glycaemic outcomes included a body mass index >40 kg/m² and co-morbidities including nephropathy and stroke.

Conclusions: In people with uncontrolled T2D (HbA1c ≥9%), glycaemic outcome achievement on premixed insulin was low at 6 months with little additional clinical benefit beyond 12 months, suggesting a high unmet need for early, timely treatment changes with more effective, simpler therapies.