Conjunctival ocular staining score (OSS) is associated with systemic biomarkers of primary Sjögren syndrome (pSS), suggesting conjunctival staining should be evaluated when pSS is suspected as a cause of dry eye disease (DED) symptoms, according to research published in Joint Bone Spine.
The investigators conducted a retrospective cross-sectional study using data from the French reference center for pSS to test for associations between ophthalmological features and the main systemic biomarkers of pSS. The team also sought to identify systemic biomarkers associated with severe keratoconjunctivitis sicca (KCS) in pSS patients.
The researchers included data from the initial visit of patients with confirmed pSS. These data included Schirmer’s test, tear break-up time, OSS, and visual analogue scale (DED-VAS) for dry eye disease (DED) symptoms as well as results of minor salivary gland biopsy, unstimulated whole salivary flow rate, anti-SSA/Ro antibodies, anti-SSB/La antibodies, and rheumatoid factor (RF).
The study included 253 patients with pSS (96.8% women mean age 56.6 years) and 108 patients with sicca symptoms who did not fulfill pSS criteria (control group; 90.7% women, mean age 56.4 years).
Using multivariate analysis, the researchers demonstrated that conjunctival OSS was associated with presence of anti-SSA/Ro antibodies in 64.8% of patients with pSS (OR 1.25 per OSS unit increase; 95% CI, 1.05-1.49; P =.01).
“While both DED-VAS ≥5 and positive anti-SSB/La alone had poor positive and negative predictive values for severe KCS, their combination reached a [positive predictive value] of 69 % and [negative predictive value] of 79%, suggesting that they could function as a combined predictive factor for severe KCS,” the researchers explain.
They also found that severe KCS was significantly associated with both anti-SSB/La antibodies (OR, 2.03; 95% CI, 1.03-4.00; P <.05) and DED-VAS of at least 5 (OR, 2.52; 95% CI, 1.31-4.90; P <.01), and 37% of patients with pSS present with severe KCS. Anti-SSB/Ro antibodies and RF were more frequently positive in these patients (45% vs 28%, P <.01 and 53% vs 38%, P =.001, respectively).
“We observed a significant association between conjunctival staining and systemic biological biomarkers of pSS patients, suggesting that conjunctival staining, a biomarker easy to assess in everyday clinical practice, is crucial when suspecting pSS as a cause of DED. Conversely, positive anti-SSB and DED-VAS ≥5 are associated with severe KCS, so patients with these features should be prioritized for ophthalmological evaluation,” researchers report.
Limitations of the study include the retrospective design and subjective nature of the DED-VAS test for evaluating DED symptoms.
Cunha ED, Mariette X, Desmoulins F, et al. Associations between ocular and extra-ocular assessment in primary Sjögren’s syndrome. Joint Bone Spine. Published online June 15, 2022. doi:10.1016/j.jbspin.2022.105426