Batool Almoallem, Nandu K Thalange
The convergence of type 1 diabetes (T1D) and features of type 2 diabetes, such as obesity and insulin resistance, has given rise to the concept of "double diabetes" (DD). This condition poses significant management challenges in the pediatric population, as escalating insulin requirements may exacerbate weight gain and insulin resistance, creating a vicious cycle. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are not approved for pediatric T1D but represent a potential therapeutic avenue. We present the case of an 11-year-old girl with antibody-positive T1D on an insulin pump who developed significant features of DD, including obesity, acanthosis nigricans, and escalating insulin requirements that exceeded her pump reservoir capacity. To address both insulin deficiency and severe insulin resistance, a novel off-label approach was initiated using a fixed-ratio combination of basal insulin degludec and the GLP-1 RA liraglutide (IDegLira), administered once daily as an adjunct to her continued insulin pump therapy for bolus insulin delivery. Over an eight-month follow-up period, the patient demonstrated modest weight loss (-2.2 kg) and a reduction in BMI z-score, with a marked improvement in glycemic control. Her mean glucose decreased from 196 mg/dL to 139 mg/dL, and her glucose management indicator improved from 8.0% to 6.6%. Time spent in severe hyperglycemia (>250 mg/dL) was reduced from 26% to 15%. The adjunctive therapy reduced the total daily insulin dose delivered via the pump. This case report highlights the potential utility of a pragmatic, off-label approach that combines a fixed-ratio GLP-1 RA with basal insulin to manage the challenges of pediatric DD. It addressed insulin resistance, improved glycemic control, and mitigated the burdensome cycle of weight gain and escalating insulin doses. This report underscores the need for further research into tailored, multifaceted therapeutic strategies for this growing patient population.