Background Patient reported outcome (PRO) tools are uniquely informative for management of systemic lupus erythematosus (SLE) patients. Fatigue is an important component of PRO. Patients with SLE experience significant fatigue and its association with standard disease activity measures in SLE is inconsistent.
Objectives To compare patient self-reported fatigue using two different PRO tools – Multi-dimensional health assessment questionnaire (MDHAQ) and LupusPRO (a disease-specific PRO for SLE) in patients with and without a current SLE flare as determined by the SELENA flare Index (SFI).
Methods 121 patients meeting ACR criteria for SLE completed MDHAQ and LupusPRO during a routine clinic visit. Disease activity assessments were made by SELENA-SLEDAI Physician global assessment (SLEDAI-PGA), total SLEDAI and SFI. Fatigue on MDHAQ (MDHAQ-F) was marked on a visual analogue scale of 0-10. Fatigue from LupusPRO was calculated on a scale of 0-100 using 5 Pain-Vitality domain questions on pain and fatigue. LupusPRO Pain-Vitality scores were coded to reflect greater fatigue with an increase in scores. Independent sample t-test was used to compare fatigue by SFI status. Data were then stratified by physician diagnosis of fibromyalgia (FM) (yes/no). Spearman rho correlation was used. A p value of ≤0.05 was considered statistically significant on two tailed tests.
Results Mean (SD) age, SLEDAI-PGA and total SELENA-SLEDAI scores were 43.2 (13.3) yrs., 0.6 (0.6) and 4.1 (4.7). 95% of the patients were female and 52% were African-American. Mean (SD) MDHAQ-F was 4.5 (3.4) and on LupusPRO Pain-Vitality was 40.0 (29.3). MDHAQ-F and LupusPRO Pain-Vitality were strongly correlated (rho 0.79 (P<0.001)). Twenty one percent had a current SFI flare. Nearly ¼ of SLE patients had a diagnosis of FM. Mean (SD) MDHAQ-F were 3.9 (3.3) and 6.2 (3.0) among patients without and with SFI flare (p=0.003) (Table 1). Mean (SD) LupusPRO Pain-Vitality were 35.1 (28.6) and 53.8 (25.8) (p=0.005) in patients without and with SFI flare. Patients who did not have FM had mean (SD) MDHAQ-F scores without and with SFI flare of 2.7 (2.7) and 6.2 (2.8) (p≤0.001) and mean (SD) LupusPRO Pain-Vitality scores without and with SFI flare of24.0 (22.9) and 51.1 (25.4), (p<0.001). In these patients without FM, MDHAQ-F and LupusPRO Pain-Vitality were correlated significantly with SLEDAI PGA and Total SLEDAI (Table). In patients with FM, MDHAQ-F and LupusPRO Pain-Vitality scores did not differ significantly by SFI status and no significant correlation with SLEDAI-PGA or Total SLEDAI was seen (Table).
Conclusions Patient self-reported fatigue scores are directly related to flares, and should be explored as a possible surrogate marker of SLE flares in patients with SLE not confounded by FM. Further studies are needed to study the responsiveness to change in self-reported fatigue with change in SFI status.
Disclosure of Interest None declared