OBJECTIVE
Our aim was to assess whether erythrocyte sedimentation rate (ESR) levels correlate with the level of disease activity at each visit and whether a change in ESR could be useful in predicting changes in disease activity.
METHODS
Thousands of visits in a prospective systemic lupus erythematosus (SLE) cohort were analyzed to assess the association of ESR and level of disease activity. We explored whether ESR was cross-sectionally associated with disease activity, whether changes in ESR were associated with changes in disease activity, and whether changes in ESR predicted future changes in disease activity. Visits when patients had cancer, infection, pregnancy or were in renal failure were excluded.
RESULTS
After adjusting for confounding factors, mild (25-50 mm/h), moderate (51-75 mm/h), and marked (>75 mm/h) elevations in ESR levels at a given visit correlated with the SELENA-SLEDAI, the Physician Global Assessment (PGA), fatigue, renal, joint, rash, serositis, hematological visual analogue scale (VAS), hematuria and proteinuria (p<0.0001) levels at that visit. A change in ESR between two visits was highly correlated with a concurrent change in PGA, renal, fatigue and joint VAS (p<0.0001). There was no statistically significant correlation between change in ESR between two visits and change in disease activity at a future visit. The subgroup analysis of patients who do not have anti-dsDNA and low complement levels as a feature of their disease showed ESR to be positively associated with SLEDAI, PGA, renal and joint VAS at that visit (p<0.0001), but there were few significant associations between changes in ESR and changes in disease activity.
CONCLUSION
ESR is associated with disease activity in SLE measured by the SELENA-SLEDAI, the PGA, and with organ-specific activity including serositis, rash, joint, renal and hematological VAS. Grouping baseline ESR into four levels does associate with both global and organ-specific disease activity. A change in ESR between two visits was highly correlated with a change in PGA, renal, fatigue and joint VAS. In patients without anti-dsDNA and low complement levels, ESR was positively associated with SLEDAI, PGA, renal and joint VAS at the same visit. Until more specific biomarkers are validated, serial ESR does have some utility in following disease activity in SLE.