Background: Optimal glycemic control and proper basal insulin initiation timing when non-insulin treatment becomes insufficient is critical in type 2 diabetes mellitus (T2DM). The DUNE study investigated the effectiveness and safety of newly initiated basal insulin in T2DM patients compared to those who already received insulin. The impact of background therapy with sulfonylureas (SU) on insulin dose and hypoglycemia occurrence was also explored.

Methods: The DUNE study was a 12-week, prospective, single-arm, observational study of adults with T2DM. The present sub-analysis included the patients from the Balkan region (Slovenia and Serbia). The first group (n=83) included patients with newly initiated basal insulin and the second group (n=94) included patients who were already treated with basal insulin for up to 12 months. Patients also received other non-insulin antihyperglycemic drugs.

Results: The proportion of patients receiving SUs was higher in the group with newly initiated basal insulin (72.3% vs. 55.3%; p<0.001). Basal insulin treatment included NPH or 1st generation basal insulin analogues (BIA) (98.8% vs. 1.2% for newly initiated basal insulin and 83% vs. 17% for already initiated basal insulin), due to local reimbursement policy. Daily insulin doses were lower in newly initiated basal insulin group (11.7±5.58U vs. 18.6±9.18U; p<0.001), the difference remained significant also after 12 weeks of observation (17.5±11.8U vs. 22.6±10.69U; p<0.01). A trend towards higher hypoglycemia occurrence in the newly initiated basal insulin group was observed, despite the lower insulin dose, but with higher percentage of treatment with SUs as a background treatment.

Conclusions: Continuation of SUs in T2DM patients, both newly initiated and already initiated with basal insulin therapy (NPH or first-generation insulin analog), should be considered with caution due to the potentially enhanced effect on the risk of hypoglycemia.


A. Janez: None. M. Lunder: None. M. Janic: None. N. Grulovic: None. D. Zdravkovic: None. A.Z. Jotic: None. K. Lalic: Speaker’s Bureau; Self; AstraZeneca, Boehringer Ingelheim, Merck, Novo Nordisk, Sanofi. N. Lalic: None.

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at