Obesity, insulin resistance, and type 1 diabetes mellitus.

PURPOSE OF REVIEW: To summarize recent studies about obesity, insulin resistance, and type 1 diabetes mellitus (T1DM).

RECENT FINDINGS: Overweight and obesity continue to be prevalent among individuals with T1DM. Obesity rates appear to have reached a plateau among children with T1DM in some parts of the world. The risk for development of T1DM is increased by obesity and may occur at an earlier age among obese individuals with a predisposition. Obesity increases the risk for comorbidities among individuals with T1DM, especially metabolic syndrome, and microvascular and macrovascular diseases. Metformin, glucagon-like peptide-1 agonist therapy, sodium glucose cotransporter-2 inhibitor therapy, and bariatric surgery may be beneficial therapies for glucose control, comorbidity management, and obesity among adults with T1DM. Insulin resistance may be improved among obese individuals with T1DM by biguanides (metformin) and glucagon-like peptide-1 agonists (exenatide).

SUMMARY: We review the last 18 months of literature on obesity, insulin resistance, and T1DM to highlight new epidemiologic results and treatments.