Newer long-acting insulins (insulin glargin 300 U/ml and insulin degludec) are not recommended for the treatment of patients with type 2 diabetes mellitus (T2DM) according to the Dutch guideline ‘NHG-Standaard diabetes mellitus type 2'. Although adherence to guidelines is generally high among Dutch GPs, the popularity of insulin glargine 300 U/ml and insulin degludec in Dutch practice is rapidly increasing. This study therefore aimed to identify practice variation in, and practice and patient characteristics associated with, the prescription of newer insulins to patients with T2DM in primary care, 3–5 years after their introduction.

We performed a retrospective cohort study in Dutch general practices using data of the Nivel Primary Care Database. We found that a median percentage of 21.2% of all patients prescribed intermediate or long-acting insulins per practice received a prescription for newer insulins. The inter-practice variation in the prescription of newer insulins was large and could only be partially explained by patient- and practice-related differences. This indicates substantial opportunities for improvement.