To identify the principal determinants of health-related quality of life (HRQOL) impairment in patients with active primary Sjögren's syndrome (SS) participating in a large therapeutic trial, Tolerance and Efficacy of Rituximab in Primary Sjögren's Syndrome (TEARS).
At the inclusion visit for the TEARS trial, 120 patients with active primary SS completed the Short Form 36 health survey (SF-36), a validated HRQOL assessment tool. Univariate then multivariate linear regression analyses were used to assess associations linking SF-36 physical and mental components to demographic data, patient-reported outcomes (symptom intensity assessments for dryness, pain, and fatigue, including the European League Against Rheumatism [EULAR] Sjögren's Syndrome Patient Reported Index [ESSPRI]), objective measures of dryness and autoimmunity, and physician evaluation of systemic activity (using the EULAR Sjögren's Syndrome Disease Activity Index [ESSDAI]).
SF-36 scores indicated marked HRQOL impairments in our population with active primary SS. Approximately one-third of the patients had low, moderate, and high systemic activity according to the ESSDAI. ESSPRI and ESSDAI scores were moderately but significantly correlated. The factors most strongly associated with HRQOL impairment were patient-reported symptoms, best assessed using the ESSPRI, with pain and ocular dryness intensity showing independent associations with HRQOL. Conversely, systemic activity level was not associated with HRQOL impairment in multivariate analyses, even in the patient subset with ESSDAI values indicating moderate-to-high systemic activity.
The cardinal symptoms of primary SS (dryness, pain, and fatigue, best assessed using the ESSPRI) are stronger predictors of HRQOL impairment than systemic involvement (assessed by the ESSDAI) and should be used as end points in future therapeutic trials focusing on patients' well-being. New consensual and data-driven response criteria are needed for primary SS studies.