Depression and quality of life in patients with systemic lupus erythematosus

Abstract

Introduction: Patients with systemic lupus erythematosus (SLE) are vulnerable to depression because of the chronic nature and neuropsychiatric involvement of the disease. Levels of serum brain-derived neurotrophic factor (BDNF) and vitamin D are reported to be decreased in patients with depression. The aim of the study was to investigate the prevalence of depression and its related factors including quality of life, BDNF and vitamin D in patients with SLE. Methods: A total of 180 patients were enrolled at the Rheumatology Clinic from January to March 2012. The prevalence of depression was assessed using the center for epidemiologic studies depression (CES-D) scale. We evaluated the physicians global assessment, patients global assessment (PGA), SLE disease activity index (SLEDAI), and disease-related organ damage. The EuroQol-5 dimensions (EQ-5D), sociodemographic features, and laboratory tests including serum vitamin D level were also surveyed. Serum BDNF was measured using an enzyme-linked immunosorbent assay. Patients with a CES-D score ≥ 24 were considered to have depression. Results: The prevalence of depression in SLE was 22.8% (n = 41). On multivariate analysis, patients with a marital status of single/divorced/ separated/widowed, higher PGA score, and extreme pain/discomfort were significantly associated with depression. The EQ-5D index was negatively correlated with CES-D score (r = − 0.56, p = 1.72 × 10−16). Analyzing associated clinical factors in each EQ-5D dimension, depression was significantly associated with moderate to severe problems in self-care (p = 0.01) and usual activities (p = 4.98 × 10-2) and extreme pain/discomfort (p = 0.01). Serum BDNF levels were not associated with depression (p = 0.62) but they were highly associated with platelet counts (r = 0.53, p = 2.16 × 10−12). As platelet is the major storage source of serum BDNF, partial correlation analysis was conducted with adjustment for platelet count. As a result, serum BDNF levels were significantly associated with age (r = 0.17, p = 0.03), hemoglobin levels (r = − 0.30, p= 1.75 × 10−4) and SLEDAI (r = − 0.21, p = 0.010). On partial correlation analysis adjusted with use of vitamin D supplement, serum vitamin D levels were not associated with depression (p = 0.59) but they were correlated with age (r = 0.28, p = 0.01), SLEDAI (r = − 0.23, p = 0.02) and mean glucocorticoid dose over the previous 3 months (r = − 0.21, p = 0.04). Conclusion: Depression is prevalent in patients with SLE, especially those with a marital status of single/divorced/separated/widowed, a higher PGA, and extreme pain/discomfort. Patients with depression had low quality of life. Serum BDNF and vitamin D levels were not associated with depression.