Identification of distinct subgroups of Sjögren's disease by cluster analysis based on clinical and biological manifestations: data from the cross-sectional Paris-Saclay and the prospective ASSESS cohorts.

BACKGROUND: Sjögren's disease is a heterogenous autoimmune disease with a wide range of symptoms-including dryness, fatigue, and pain-in addition to systemic manifestations and an increased risk of lymphoma. We aimed to identify distinct subgroups of the disease, using cluster analysis based on subjective symptoms and clinical and biological manifestations, and to compare the prognoses of patients in these subgroups. METHODS: This study included patients with Sjögren's disease from two independent cohorts in France: the cross-sectional Paris-Saclay cohort and the prospective Assessment of Systemic Signs and Evolution of Sjögren's Syndrome (ASSESS) cohort. We first used an unsupervised multiple correspondence analysis to identify clusters within the Paris-Saclay cohort using 26 variables comprising patient-reported symptoms and clinical and biological manifestations. Next, we validated these clusters using patients from the ASSESS cohort. Changes in disease activity (measured by the European Alliance of Associations for Rheumatology [EULAR] Sjögren's Syndrome Disease Activity Index [ESSDAI]), patient-acceptable symptom state (measured by the EULAR Sjögren's Syndrome Patient Reported Index [ESSPRI]), and lymphoma incidence during follow-up were compared between clusters. Finally, we compared our clusters with the symptom-based subgroups previously described by Tarn and colleagues. FINDINGS: 534 patients from the Paris-Saclay cohort (502 [94%] women, 32 [6%] men, median age 54 years [IQR 43-64]), recruited between 1999 and 2022, and 395 patients from the ASSESS cohort (370 [94%] women, 25 [6%] men, median age 53 years [43-63]), recruited between 2006 and 2009, were included in this study. In both cohorts, hierarchical cluster analysis revealed three distinct subgroups of patients: those with B-cell active disease and low symptom burden (BALS), those with high systemic disease activity (HSA), and those with low systemic disease activity and high symptom burden (LSAHS). During follow-up in the ASSESS cohort, disease activity and symptom states worsened for patients in the BALS cluster (67 [36%] of 186 patients with ESSPRI score <5 at month 60 vs 92 [49%] of 186 at inclusion; p<0·0001). Lymphomas occurred in patients in the BALS cluster (five [3%] of 186 patients; diagnosed a median of 70 months [IQR 42-104] after inclusion) and the HSA cluster (six [4%] of 158 patients; diagnosed 23 months [13-83] after inclusion). All patients from the Paris-Saclay cohort with a history of lymphoma were in the BALS and HSA clusters. This unsupervised clustering classification based on symptoms and clinical and biological manifestations did not correlate with a previous classification based on symptoms only. INTERPRETATION: On the basis of symptoms and clinical and biological manifestations, we identified three distinct subgroups of patients with Sjögren's disease with different prognoses. Our results suggest that these subgroups represent different heterogeneous pathophysiological disease mechanisms, stages of disease, or both. These findings could be of interest when stratifying patients in future therapeutic trials. FUNDING: Fondation pour la Recherche Médicale, French Ministry of Health, French Society of Rheumatology, Innovative Medicines Initiative 2 Joint Undertaking, Medical Research Council UK, and Foundation for Research in Rheumatology.

Pregnancy outcomes in women with primary Sjögren's syndrome: an analysis of data from the multicentre, prospective, GR2 study.

BACKGROUND: Adverse pregnancy outcomes in women with primary Sjögren's syndrome have only been evaluated retrospectively using heterogeneous methods and with contradictory results. We aimed to describe adverse pregnancy, delivery, and birth outcome risks in pregnant women with primary Sjögren's syndrome compared with those of a matched general population in France, and to identify factors predictive of disease flares or adverse pregnancy outcomes. METHODS: We conducted a multicentre, prospective, cohort study in France using the GR2 (Groupe de Recherche sur la Grossesse et les Maladies Rares) registry. Women from the GR2 study were eligible if they had conceived before March, 2021, had primary Sjögren's syndrome according to the American College of Rheumatology and European Alliance of Associations for Rheumatology (EULAR) 2016 classification criteria, and had an ongoing pregnancy at 12 weeks of gestation. In women who entered in the registry with pregnancies before 18 weeks of gestation, we sought to identify factors associated with primary Sjögren's syndrome flare (≥3-point increase in EULAR Sjögren's Syndrome Disease Activity Index [ESSDAI] score) or adverse pregnancy outcomes (fetal or neonatal death, placental insufficiency leading to a preterm delivery [<37 weeks of gestation], or small-for-gestational-age birthweight). A matched controlled study compared adverse pregnancy, delivery, and birth outcome rates between pregnant women with primary Sjögren's syndrome from the GR2 registry and matched controls from the general population included in the last French perinatal survey (Enquête Nationale Périnatale 2016). FINDINGS: 1944 pregnancies were identified in the GR2 cohort, of which 106 pregnancies in 96 women with primary Sjögren's syndrome were included in this analysis. The median age at pregnancy onset was 33 years (IQR 31-36). 87 (83%) of 105 pregnancies (with ethnicity data) were in White women, 18 (17%) were in Black women; 92 (90%) of 102 had previous systemic activity (ESSDAI score of ≥1; data missing in four pregnancies), and 48 (45%) of 106 had systemic activity at inclusion. Of 93 pregnancies included at week 18 of gestation or earlier, primary Sjögren's syndrome flares occurred in 12 (13%). No baseline parameters were associated with primary Sjögren's syndrome flare. Four twin pregnancies and one medical termination were excluded from the adverse pregnancy outcome analysis; of the remaining 88, adverse pregnancy outcomes occurred in six (7%). Among pregnancies in women with data for antiphospholipid antibodies (n=55), antiphospholipid antibody positivity was more frequent among pregnancies with adverse outcomes (two [50%] of four pregnancies) compared with those without adverse outcomes (two [4%] of 51 pregnancies; p=0·023). Anti-RNP antibody positivity was also more frequent among pregnancies with adverse outcomes than those without, although this was not statistically significant. In the matched controlled study, adverse pregnancy outcomes occurred in nine (9%) of 105 pregnancies in women with primary Sjögren's syndrome and 28 (7%) of the 420 matched control pregnancies; adverse pregnancy outcomes were not significantly associated with primary Sjögren's syndrome (odds ratio 1·31, 95% CI 0·53-2·98; p=0·52). INTERPRETATION: Pregnancies in women with primary Sjögren's syndrome had very good prognoses for mothers and fetuses, with no overall increase in adverse pregnancy outcome risk compared with the general population. Women with antiphospholipid antibodies or anti-RNP antibodies require close monitoring, because these factors might be associated with a higher risk of adverse pregnancy outcomes. FUNDING: Lupus France, Association des Sclérodermiques de France, Association Gougerot Sjögren, Association Francophone Contre la Polychondrite Chronique Atrophiante, AFM-Telethon, Société Nationale Française de Médecine Interne, Société Française de Rhumatologie, Cochin Hospital, French Health Ministry, Fondation for Research in Rheumatology, Association Prix Véronique Roualet, Union Chimique Belge.