Objectives: To identify the socioeconomic status, disease activity and psychiatric disorders that contribute to the health-related quality of life (HRQOL) in systemic lupus erythematosus (SLE) patients.
Methods: Data were collected from 170 SLE patients and 210 healthy individuals. All of the patients fulfilled the criteria for the classification of SLE and underwent disease activity assessment according to the SLE disease activity index (SLEDAI). Self-rated scales for anxiety (SAS) and depression (SDS) were used to evaluate the levels of anxiety and depression. The patients' general health status was measured using the Short Form (SF)-36 questionnaire. To provide greater clarity regarding the determinants of HRQOL, path analysis was used to explore the relationships between the various predictors and the health-related quality of life (HRQoL).
Results: SLE patients who have depression and anxiety are more likely to have a lower quality of life compared to those who are not depressed (r=-0.735, p<0.01; r=-0.684, p<0.01). All of the variables were significantly correlated with depression except age, gender and marital status. Education was negatively correlated with disease activity (r=-0.272, p<0.05) and anxiety (r=-0.312, p<0.01). Disease activity was positively correlated with anxiety (r=0.198, p<0.05). In addition, work status also correlated with anxiety (r=-0.294, p<0.01). A path-analytic models analysis suggested that the main influencing factors of HRQoL are the following: depression, anxiety, education level, income/family, disease activity, age, and work status. A χ2 test (χ215=17.71, p=0.28>0.05) indicated that the path analysis model had an adequate goodness of fit value. Depression (β=-0.616, p<0.05) contributed the most to HRQOL. Depression, anxiety and disease activity contributed to HRQoL both directly and indirectly through other factors. Socioeconomic factors such as education, income/family and work status, however, did not contribute directly to HRQoL.
Conclusions: HRQoL in SLE is influenced by disease activity and psychiatric disorders. Socioeconomic status has no direct influence on the quality of life of lupus patients, while disease activity has a direct impact on the quality of life. Anxiety and depression were significant predictors of poor HRQoL. Understanding how these factors are inter-related may help clinicians focus their assessments and develop strategies to improve the HRQoL of lupus patients.