China: Sitagliptin Plus Insulin Treatment in LADA

Sitagliptin plus insulin treatment improves insulin sensitivity and maintains β-cell function in latent autoimmune diabetes in adults (LADA) compared to insulin treatment alone, finds a recent study in the Journal of Clinical Endocrinology & Metabolism.

The long-term effects of dipeptidyl peptidase-4 inhibitors on insulin sensitivity and β-cell function in LADA are not clear. Zhiguang Zhou, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China, and colleagues, therefore, aimed to investigate the effects of sitagliptin on β-cell function and insulin sensitivity in LADA patients receiving insulin.

For the purpose, the researchers performed a randomized controlled trial at the Second Xiangya Hospital. It included 51 LADA patients who were randomized to either sitagliptin + insulin group (SITA group) or insulin alone group (CONT group) for 24 months.

Fasting C-peptide (FCP), 2-hour postprandial C-peptide (2hCP) during mixed-meal tolerance test, △CP (2hCP - FCP) and updated homeostatic model assessment of β-cell function (HOMA2-B) were determined every 6 months. Hyperglycemic clamp and hyperinsulinemic euglycemic clamp (HEC) tests were further conducted at 12-month intervals in 12 subjects.

Key Findings of the Study

• During the 24-month follow-up, there were no significant changes in β-cell function in SITA group, whereas the levels of 2hCP and △CP in CONT group were reduced at 24 months.
• The changes in HOMA2-B from baseline were larger in SITA group than in CONT group.
• At 24 months, first-phase insulin secretion was improved in SITA group by hyperglycemia clamp, which was higher than in CONT group, while glucose metabolized (M), insulin sensitivity index, and M over logarithmical insulin ratio in HEC were increased in SITA group, which were higher than in CONT group.

"Compared with insulin intervention alone, sitagliptin plus insulin treatment appeared to maintain β-cell function and improve insulin sensitivity in LADA to some extent," concluded the authors.

The study titled, "Islet function and insulin sensitivity in latent autoimmune diabetes in adults taking sitagliptin: A randomized trial," is published in the Journal of Clinical Endocrinology & Metabolism.

DOI: https://academic.oup.com/jcem/advance-article/doi/10.1210/clinem/dgab026/6105049