The association between metabolic dysfunction-associated fatty liver disease and left ventricular mass index in patients with schizophrenia with long-term hospitalization.

BACKGROUND: Patients with schizophrenia have a high cardiovascular risk, especially long-term hospitalized cases where physical issues are prominent due to prolonged illness, lifestyle restrictions, and antipsychotic use. Metabolic dysfunction-associated fatty liver disease (MAFLD) is an independent cardiovascular risk factor, but its association with cardiac remodeling remains unclear. This study investigates this relationship to support early screening and targeted intervention. METHODS: This study included 430 long-term hospitalized patients with schizophrenia. Echocardiography was used to assess left ventricular mass index (LVMI), and ultrasound to diagnose MAFLD. Demographic, clinical, metabolic, and comorbidity data were collected. Spearman correlation and multiple linear regression were performed to examine the association between MAFLD and LVMI. All analyses were conducted using R, with a two-tailed significance level of α=0.05. Bias-corrected bootstrap mediation analysis was used to assess the mediating role of hypertension and fasting blood glucose. RESULTS: MAFLD was identified in 231 cases (53.7%) of 430 long-term hospitalized patients with schizophrenia. Compared to patients without MAFLD, those with MAFLD had significantly higher LVMI values (78.79 vs 73.95 g/m², mean difference=4.84, 95%CI: 1.2-8.5, p=0.009). A positive association between MAFLD and LVMI was found using Spearman correlation analysis (r=0.126, p=0.009). Multivariate regression analysis revealed that after adjusting for age, sex, and hypertension, the presence of MAFLD remained positively associated with LVMI (β=3.53, 95%CI: 0.49-6.57, p=0.023). Further mediation analysis indicated that MAFLD had a significant total effect on LVMI (4.178, 95%CI: 1.02-7.34, p=0.010), with hypertension playing a key mediating role in this relationship (indirect effect=1.244, 95%CI: 0.35-2.14, p=0.007), accounting for 29.8% of the total effect. The direct effect of MAFLD on LVMI was not significant after accounting for the mediator (β=2.618, 95%CI: -0.54-5.78, p=0.104). CONCLUSION: In this study of long-term hospitalized schizophrenia patients, the total association between MAFLD and LVMI was significant, with a 53.7% prevalence and significantly higher LVMI in affected individuals. Hypertension served as a significant mediator of this relationship, suggesting that the association between MAFLD and cardiac structural remodeling in this population is largely explained by hypertensive pathways. These findings identify MAFLD and hypertension as important metabolic and vascular targets for cardiovascular risk stratification in this population.