A cross-sectional study on activity impairment in primary Sjogren's syndrome

The aim of this cross-sectional study was to show relations between activity impairment and salivary gland involvement for patient empowerment in primary Sjogren's syndrome (pSS).

In the study, 86 patients with pSS were included. The data were collected through clinical examinations and a questionnaire regarding Work Productivity and Activity Impairment (WPAI), EULAR Sjogren's syndrome patient-reported index (ESSPRI) and Oral Health Impact Profile-14 (OHIP-14). Relations were analysed by using mediation and moderation analyses. In simple mediation analysis, an independent variable (X) influences outcome variable (Y) through a mediator variable (M) whereas a moderator variable (W) affects the direction of the relationship between the dependent (Y) and independent variables (X).

Increases in ESSPRI-Dryness score (X) (p = 0.0189) and OHIP-14 score (M) (p = 0.0004) were associated with the poor WPAI activity impairment score (Y) in the first mediation analysis. The WPAI activity impairment score was mediated by the elevated ESSPRI-Fatigue score (X) (p = 0.03641) and low U-SFR (M) (p = 0.0000) in the second mediation analysis. In addition, ESSPRI-Pain score (W) was the significant moderator for WPAI activity impairment (Y) in patients without hyposalivation in the moderation analysis (p = 0.0010).

WPAI activity impairment was affected by both ESSPRI-Dryness with OHRQoL and ESSPRI-Fatigue with SFR in glandular involvement.