Association between serum β2-microglobulin and left ventricular hypertrophy in patients with type 2 diabetes mellitus: A cross-sectional study

Background: Beta 2-microglobulin (beta 2-MG) is a component of the class I major histocompatibility complex (MHCI) and has recently been reported to be involved in type 2 diabetes mellitus (T2DM) and cardiovascular disease. However, the association of beta 2-MG with left ventricular hypertrophy (LVH) in T2DM patients remains unknown. This study aims to investigate the correlation between serum beta 2-MG and LVH in T2DM patients. Methods: The retrospective analysis included 4602 eligible T2DM patients, divided into LVH and non-LVH groups based on echocardiography results. Serum beta 2-MG levels were measured, and participants were categorized into four groups (Q1-Q4) by their serum beta 2-MG quartile. The relationship of serum beta 2-MG level with LVH was evaluated using logistic regression, restricted cubic spline (RCS), subgroup analysis, and machine learning. Results: The prevalence of LVH in T2DM patients was 31.12%. Each standard deviation increase in serum beta 2-MG level corresponded to a 1.17-fold increase in the prevalence of LVH [OR = 1.17, (95% CI: 1.05-1.31); p = 0.006]. When considering beta 2-MG as a categorical variable (quartile), Q3 [OR = 1.36, (95% CI: 1.09-1.69); p = 0.007] and Q4 [OR = 1.77, (95% CI: 1.36-2.31); p < 0.001] had a significantly higher prevalence of LVH than Q1. RCS analysis found a nonlinear association between beta 2-MG and LVH prevalence (p for nonlinearity <0.05). Additionally, machine learning results confirmed the importance of beta 2-MG for LVH in T2DM patients. Conclusion: Elevated serum beta 2-MG levels were likely to be associated with an increased prevalence of LVH in T2DM patients, suggesting its potential role in LVH development.