Sidorenkov G, et al. - In this cohort study, the researchers identified subgroups of patients with type 2 diabetes mellitus (T2DM) following distinct trajectories of HbA1c after the start of insulin, and explored underlying differences in clinical characteristics. This investigation was performed on patients with T2DM starting insulin in 2007–2013 with a follow-up of 2 to 4 years. After insulin initiation, most patients showed a stable HbA1c response, but 1 out of 6 patients showed either a poor response or a rapid initial response only. It was observed that response patterns were correlated with age, diabetes duration and risk-factor controls at the time of insulin was begun.