Association of point in range with β-cell function and insulin sensitivity of type 2 diabetes mellitus in cold areas

Abstract

Abstract Background and Objective Self-monitoring of blood glucose (SMBG) is crucial for achieving a glycemic target and upholding blood glucose stability, both of which are the primary purpose of anti-diabetic treatments. However, the association between time in range (TIR), as assessed by SMBG, and β-cell insulin secretion as well as insulin sensitivity remains unexplored. Therefore, this study aims to investigate the connections between TIR, derived from SMBG, and indices representing β-cell functionality and insulin sensitivity. The primary objective of this study was to elucidate the relationship between short-term glycemic control (measured as points in range [PIR]) and both β-cell function and insulin sensitivity. Methods This cross-sectional study enrolled 472 hospitalized patients with type 2 diabetes mellitus (T2DM). To assess β-cell secretion capacity, we employed the insulin secretion-sensitivity index-2 (ISSI-2) and (ΔC-peptide0–120/Δglucose0–120) × Matsuda index, while insulin sensitivity was evaluated using the Matsuda index and HOMA-IR. Since SMBG offers glucose data at specific point-in-time, we substituted TIR with PIR. According to clinical guidelines, values falling within the range of 3.9–10 mmol were considered “in range, ” and the corresponding percentage was calculated as PIR. Results We observed significant associations between higher PIR quartiles and increased ISSI-2, (ΔC-peptide0–120/Δglucose0–120) × Matsuda index, Matsuda index (increased) and HOMA-IR (decreased) (all P < 0.001). PIR exhibited positive correlations with log ISSI-2 (r = 0.361, P < 0.001), log (ΔC-peptide0–120/Δglucose0–120) × Matsuda index (r = 0.482, P < 0.001), and log Matsuda index (r = 0.178, P < 0.001) and negative correlations with log HOMA-IR (r = -0.288, P < 0.001). Furthermore, PIR emerged as an independent risk factor for log ISSI-2, log (ΔC-peptide0–120/Δglucose0–120) × Matsuda index, log Matsuda index, and log HOMA-IR. Conclusion PIR can serve as a valuable tool for assessing β-cell function and insulin sensitivity.