Association of Depressive and Negative Symptoms with Quality of Life in Schizophrenia: A Cross-Sectional Inpatient Study

Background/Objectives: Identifying the factor most strongly associated with patients’ quality of life (QoL) is crucial for establishing treatment goals focused on improved recovery. This study aimed to determine whether sociodemographic factors, negative, or depressive symptoms have the strongest association with QoL. Methods: Inpatients diagnosed with schizophrenia were recruited. We collected data on sociodemographic factors, asked patients to rate their well-being on a subjective well-being scale, and evaluated their psychopathology using observer-rated psychometric scales (Positive and Negative Symptoms Scale (PANSS), Brief Negative Symptoms Scale (BNSS), and Calgary Depression Scale for Schizophrenia (CDSS) as well as self-rated scales (Self-evaluation Negative Symptoms Scale (SNS). QoL was evaluated using Short-Form 36 (SF-36). Patients were also divided into primary, prominent, and predominant negative symptom groups. We conducted correlation and linear regression analyses to identify which factors were most strongly associated with QoL. Results: In this study, 323 participants were included. The CDSS total score showed the strongest correlation with QoL scores, followed by negative symptoms assessed with the SNS. Positive and negative symptoms, assessed using either the PANSS or the BNSS, showed weak or insignificant correlations with QoL. Among sociodemographic factors, the subjective well-being score, previous history of hospitalization, or suicide attempts had the strongest correlation with QoL. CDSS scores were the variable with the strongest independent association with QoL in regression analysis. Conclusions: Depressive symptom severity showed the strongest and most consistent association with QoL across both correlation and multivariable analyses. These findings are hypothesis-generating and require longitudinal confirmation.