Design and rationale of the IN CONTROL trial: the effects of real-time continuous glucose monitoring on glycemia and quality of life in patients with type 1 diabetes mellitus and impaired awareness of hypoglycemia

BACKGROUND: Hypoglycemia is the main side effect of intensified insulin therapy in type 1 diabetes and recognized as a limitation in achieving glycemic targets. Patients with impaired awareness of hypoglycemia have a threefold to sixfold increased risk of severe hypoglycemia. Real-time continuous glucose monitoring may help patients with type 1 diabetes to achieve better glycemic control with less hypoglycemic episodes. Accordingly, one may hypothesize that particularly type 1 diabetes mellitus patients with impaired awareness of hypoglycemia will profit most from this technology with improvements in their quality of life. However, this has not yet been established. This trial aims to study the effect of real-time continuous glucose monitoring on glycemia and quality of life specifically in type 1 diabetes mellitus patients with established impaired awareness of hypoglycemia. METHODS/DESIGN: This is a two-center, randomized, cross-over trial with a 12-week wash-out period in between intervention periods. A total of 52 type 1 diabetes mellitus patients with impaired awareness of hypoglycemia according to Gold et al. criteria will be randomized to receive real-time continuous glucose monitoring or blinded continuous glucose monitoring for 16 weeks. After a wash-out period, patients will cross over to the other intervention. The primary outcome measure is time spent in euglycemia. Secondary outcomes include (diabetes-specific) markers of quality of life and other glycemic variables. DISCUSSION: It remains unclear whether patients with type 1 diabetes and impaired awareness of hypoglycemia benefit from real-time continuous glucose monitoring in real-life. This study will provide insight into the potential benefits of real-time continuous glucose monitoring in this patient population. TRIAL REGISTRATION: Clinicaltrials.gov: NCT01787903. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12902-015-0040-3) contains supplementary material, which is available to authorized users.