Developmental Trends of Metabolic Syndrome in the Past Two Decades: A Narrative Review.

: Metabolic syndrome (MetS) is a complex disorder characterized by insulin resistance (IR), central obesity, atherogenic dyslipidemia, and higher glucose levels. It increases the risk of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM), imposing an economic burden on the healthcare system. However, the historical origins of MetS as well as the development and evolution of its definitions have not been conclusively documented in the literature. This study seeks to enhance the understanding of the developmental trends of MetS during the preceding two decades, placing particular emphasis on the definition, diagnosis and prevalence. : An extensive search was performed from 1920 to 2023 across prominent scientific research engines, including Scopus, PubMed, MDPI, and others. : Despite advancements, many aspects of MetS remain inadequately understood. As the understanding of the nature and pathophysiology of MetS progresses, the development and refinement of its diagnostic criteria, and assessment and treatment guidelines will continue. Additionally, there exists significant variation in the global prevalence of metabolic syndrome, ranging from 14 to 39%. This prevalence is projected to increase due to the adoption of less healthy dietary patterns and sedentary lifestyles. The observed disparities in metabolic syndrome prevalence can be attributed to multiple factors, including demographic characteristics. Furthermore, the lack of a standardized definition across studies also contributes to the variation in reported prevalence rates. : Further studies focusing on the standardization of the MetS definition across different research are crucial. The establishment of consistent criteria would enhance the reliability and validity of research findings, enabling more meaningful comparisons and interpretations.