Fatigue in systemic lupus: the role of disease activity and its correlates

• Published in: Lupus 2019-02, Vol.28 (2), p.163-173
• Main Authors: Azizoddin, D R, Gandhi, N, Weinberg, S, Sengupta, M, Nicassio, P M, Jolly, M
• Format: Article
• Language: English
• Subjects: Autoimmune diseases; Clinical trials; Diagnosis; Fatigue; Fibromyalgia; Insomnia; Lupus; Pain; Patients; Quality of life; Rheumatology; Sleep; Sleep disorders; Systemic lupus erythematosus; Variables
• ISSN: 0961-2033; 1477-0962
• DOI: 10.1177/0961203318817826

Objectives Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that leads to a variety of negative health outcomes resulting from inflammation in various organ systems. Although treatment continues to advance, fatigue remains one of the most salient, poorly understood and addressed patient complaints. Understanding the mechanisms of fatigue can help guide the development of interventions to improve health outcomes. The aim of this research was to evaluate the contribution of six variables (disease activity, insomnia, depression, stress, pain and physical health) to fatigue in SLE without concomitant fibromyalgia (FM). Methods A total of 116 ethnically diverse, primarily female participants (91%) with SLE, receiving care at university medical centers, completed assessments of disease activity and quality of life outcomes (FACIT-FT, Insomnia Severity Index, Perceived Stress Scale (PSS-4), Pain Inventory, Depression-PHQ-9, and LupusPRO-physical function). All patients met the American College of Rheumatology classification criteria for SLE and did not have a known diagnosis of FM. Multivariate linear and stepwise regression analyses were conducted with fatigue (FACIT-FT) as the dependent variable, and the above six variables as independent variables. Results Mean (SD) age was 39.80 (13.87) years; 50% were African American, 21% Caucasian, 13% Hispanic, 9% Asian and 8% other. Mean (SD) FACIT-FT was 20.09 (12.76). Collectively, these six variables explained 57% of the variance in fatigue. In the multivariate model, depression, stress and pain were significantly and independently associated with fatigue, but not disease activity, sleep or physical health. Stress had the largest effect on fatigue (β 0.77, 95% CI 0.17–1.38, p = 0.01), followed by depression (β 0.66, 95% CI 0.21–1.10, p = 0.005). On stepwise regression analysis, only stress, depression and pain were retained in the model, and collectively explained 56% of the variance in fatigue. All three remained independent correlates of fatigue, with the largest contribution being stress (β 0.84, 95% CI 0.27–1.42, p = 0.005), followed by depression (β 0.79, 95% CI 0.44–1.14, p