Islet β-cell function preservation by different anti-diabetic treatments in Chinese elderly patients with type 2 diabetes mellitus.

Abstract

Background: The preservation of islet β-cell function in elderly patients with type 2 diabetes mellitus (T2DM) is a top priority for diabetic control.

Aim: To assess the preservation of islet β-cell function among elderly Chinese patients with T2DM after different anti-diabetic treatments.

Methods: In this longitudinal observational study, elderly patients with T2DM treated with insulin, oral antidiabetic drugs or a combination of both were enrolled to disclose their islet β-cell function between baseline and follow-up. Islet β-cell function was determined by the plasma Homeostasis Model for β-cell function (HOMA-β), C-peptide and area under the curve (AUC) based on oral glucose tolerance test. Changes in β-cell function (decrement or increment from baseline) between different therapy groups were the outcomes.

Results: In total, 745 elderly patients (≥ 60 years) with T2DM [insulin monotherapy, n = 105; oral anti-diabetic drugs (OAD) monotherapy, n = 321; insulin plus OAD, n = 319] had their baseline and follow-up β-cell function assessed during a median observation period of 4.5 years (range, 3.0-7.2 years). Overall, islet β-cell function (HOMA-β, fasting C-peptide, fasting insulin, AUC_c-pep, AUC_ins, AUC_c-pep/AUC_glu, AUC_ins/AUC_glu) consistently deteriorated over time regardless of the three different antidiabetic treatments. No statistical differences in decrement were observed among the three groups regarding the islet β-cell function indices. All three groups showed an increased ratio of delayed insulin secretion response after 4.5 years of observation.

Conclusion: In Chinese elderly patients with T2DM, islet β-cell function progressively declines regardless of insulin supplement or insulin plus OAD treatments.