The aim at the current study was to investigate the clinical characteristics and risk factors of Raynaud's phenomenon (RP) in patients with primary Sjögren's syndrome (pSS).
Retrospective analysis of the medical records of 333 new-onset pSS patients was performed. Demographic, clinical, and serological data were compared between individuals with and without RP. Logistic regression analysis was used to identify risk factors.
RP was present in 11.41% of the pSS patients. pSS-RP patients were younger (49.74±14.56 years vs. 54.46±13.20 years, p=0.04) and exhibited higher disease activity (11 [5.75-15] vs. 7 [4-12], p=0.03) than those without. The prevalence of lung involvement was significantly higher in pSS patients with RP (60.53% vs. 17.29%; p<0.001). A significantly higher proportion of patients with pSS-RP tested positive about antinuclear (ANA), anti-RNP, and anti-centromere antibodies (ACA) compared to those without (p=0.003, <0.001, and 0.01, respectively). Multivariate analysis identified lung involvement (odds ratio [OR]=8.81, 95% confidence interval [CI] 2.02-38.47; p=0.04), anti-RNP positive status (OR=79.41, 95% CI 12.57-501.78; p<0.0001), as well as ACA (OR=13.17, 95% CI 2.60-66.72; p=0.002) as prognostic factors for pSS-RP.
The presence of RP defined a subset of pSS with a unique phenotype, manifesting as increased lung involvement and a higher frequency of anti-RNP antibodies and ACA, as well as greater disease activity. These results suggest that RP has clinical and prognostic value of pSS patients. Further prospective studies with a larger number of subjects are warranted to confirm our findings and assess the prognostic and treatment implications of RP in pSS patients. Key Points • Raynaud's phenomenon (RP) was present in 38 (11.41%) of 333 patients with primary Sjögren's syndrome (pSS), with patients with RP exhibiting a younger age and higher disease activity. • The presence of RP indicates a subset of pSS with a unique phenotype, with manifestations including increased lung involvement and a higher frequency of anti-RNP antibodies and anti-centromere antibodies. • Patients with pSS and RP need close follow-up and long-term observation (including assessment of microangiopathy), with specific attention paid to the possible development of clinical features of systemic sclerosis.