Independent Contributions of Social Functioning Deficits and Internalized Stigma to Quality of Life in Clinically...

Quality of life (QoL) is a core outcome in schizophrenia. Guided by the biopsychosocial model, this study examined whether social functional impairment and internalized stigma independently predict QoL and mediate the impact of depressive symptoms on QoL among clinically stable patients in rural China.

In a multicenter cross-sectional survey (Chaohu City, September-October 2022), 796 clinically stable adults with schizophrenia were recruited via stratified random sampling. Participants completed standardized assessments: Patient Health Questionnaire-9 (PHQ-9), Insomnia Severity Index (ISI), Social Disability Screening Schedule (SDSS), Social Impact Scale (SIS), and WHOQOL-BREF. Analyses included hierarchical regression (entering demographics/health, health behaviors, clinical symptoms [PHQ-9, ISI], and psychosocial factors [SDSS, SIS]) and parallel mediation analysis (PROCESS Model 4).

PHQ-9, ISI, SDSS, and SIS scores differed significantly across QoL groups (all *p* <0.001). Hierarchical regression showed that explained variance increased from 2.9% (Model 1) to 21.8% (Model 4). After adjusting for all covariates, depressive severity (β = -0.230), social disability (β = -0.161), and stigma (β = -0.153) were robust negative predictors of QoL (all *p* <0.001). Mediation analyses revealed a significant total effect of depression on QoL (-0.037, 95% CI [-0.046, -0.027]). This effect was partially mediated by social disability (indirect effect: -0.005, 95% CI [-0.008, -0.002]; proportion: 13.5%) and stigma (-0.006, 95% CI [-0.009, -0.003]; 16.2%), with a significant total indirect effect accounting for 29.7% of the total effect.

Social functional impairment and internalized stigma were independent predictors of QoL and statistically mediated the relationship between depressive symptoms and poorer QoL in clinically stable schizophrenia. Moving beyond symptom control to integrated interventions targeting these psychosocial pathways is crucial for enhancing QoL, especially in resource-limited rural settings.