Redefining β-Cell Function in Type 2 Diabetes Mellitus: From Comprehensive Assessment to Precision Medicine

The global surge in type 2 diabetes mellitus (T2DM) requires a thorough understanding of pancreatic β-cell dysfunction, which remains a central determinant of the disease. However, the evaluation of β-cell insulin secretory capacity is often challenging in clinical practice due to its inherent complexity. This review presents a comprehensive technical overview of diverse assessment methodologies, ranging from conventional fasting-based indices and glucose tolerance tests to advanced mathematical modeling and artificial intelligence-driven approaches. A detailed examination of the methodological strengths and limitations of these various tools is provided to guide their appropriate clinical application. Furthermore, we explore the clinical implications of these assessments in enhancing diagnostic accuracy and tailoring therapeutic strategies. Particular emphasis is placed on the pivotal role of β-cell function evaluation in predicting and achieving diabetes remission-an emerging clinical priority. By integrating the technical landscape of β-cell assessment with practical applications, this review provide a structured framework for optimizing T2DM management and improving long-term patient outcomes.