Associations between physicians’ global assessment of disease activity and patient-reported outcomes in patients with systemic lupus erythematosus: A longitudinal study

Abstract

Objective To determine longitudinal associations between Physician Global Assessment (PGA) and patient-reported outcomes (PROs) in patients with systemic lupus erythematosus (SLE). Methods Patients attending a rheumatology clinic between 2013 and 2017 completed specific (SLEQOL) and generic (SF36) health-related quality of life (HRQoL) surveys and rated their global rating of change (GRC) at each visit. PGA, SLEDAI-2K and SLE Flare Index (SFI) were also captured on all visits. Generalised estimating equations (GEE) methods were used to examine longitudinal associations of PGA with PROs and clinical indicators. Results 337 patients were followed for a median [IQR] of 3.2 [1.6, 3.4] years (2,059 visits). High PGA (>1) was strongly associated with high SLEDAI-2K scores, the presence of flares and poor PROs. Odd ratios (OR) [95% CI] of PGA > 1 in patients with SLEDAI-2K >4 & <10 and SLEDAI-2K ≥10, compared to SLEDAI-2K ≤ 4, were 3.46 [2.36, 5.08], p < 0.001 and 6.39 [4.30, 9.49], p < 0.001, respectively. OR [95% CI] of PGA > 1 in patients with mild-to-moderate or severe flares were 2.09 [1.62, 2.71], p < 0.001 and 4.42 [3.21, 6.07], p < 0.001, respectively. Mental components of both SLEQOL (mood, self-image) and SF36 (MCS) surveys demonstrated significant associations with high PGA. After adjusting for SLEDAI-2K, one-point increase in PGA was associated with reductions in SLEQOL total score and SF36-MCS by 2.33 (regression coefficient (RC) [95% CI] = −2.33 [−3.77, −0.88], p = 0.002), and 4.16 (RC [95% CI] = −4.16 [−5.19, −3.13], p < 0.001) points, respectively. Associations of some physical components (SLEQOL-symptoms, and SF36-PCS) with PGA attenuated when adjusted for SLEDAI-2K. Patients who rated low scores of GRC, which indicate health deterioration, were twice as likely to have PGA > 1 (OR [95%CI] 1.99 [1.25, 3.16], p = 0.004). Conclusion High PGA was strongly associated with poor mental health, high disease activity and flares. This study confirms the value of PGA as an efficient assessment tool for SLE.