Currently, there are no cures available for patients with Sjögren’s syndrome, although there are some therapeutic options available for the prevention of complications and improvement of symptoms associated with the condition.
However, treatment options that have recently been developed for the management of multiple autoimmune diseases are holding promise for this patient population. In addition, quantitatively validated classification criteria have been published for patients with primary Sjögren’s syndrome (Shiboski CH, et al. Arthritis Rheumatol. 2017;69:35-45).
In 2012, criteria for identifying patients with Sjögren’s syndrome suitable for enrollment in clinical trials had been conditionally approved by the American College of Rheumatology (ACR). However, the International Sjögren’s Syndrome Criteria Working Group—comprised of researchers from the Sjögren’s International Collaborative Clinical Alliance and the European League Against Rheumatism (EULAR) Sjögren’s Task Force—strived to create classification criteria for patients displaying signs and symptoms suggestive of primary Sjögren’s syndrome that used methodology consistent with guidelines endorsed by the ACR and EULAR, and which would ultimately be approved by both organizations.
The working group included 55 clinicians from all over the world, 2 patient advocates from the United States and Europe, 1 statistician, and 2 epidemiologists. Using the same tactics that led to the creation and substantiation of the 2010 ACR/EULAR criteria for rheumatoid arthritis and the 2013 ACR/EULAR criteria for systemic sclerosis, the International Sjögren’s Syndrome Criteria Working Group finalized an introductory list of potential criteria items.
An Internet-based multicriteria decision analysis survey of 52 clinicians was used to gather expert opinion on the criteria, the results of which contributed to the assignment of a relative ranking to each of the items and subsequent whittling down of the criteria list.
The resulting criteria items were ocular stain (ocular staining score or van Bijsterveld); Schirmer’s test; focal lymphocytic sialadenitis focus score; anti-SSA/B; unstimulated whole saliva flow rate; oral symptoms; and ocular symptoms.
New Classification CriteriaThe working group then tried these draft criteria—modifying items when necessary—in 2 separate groups of patients with primary Sjögren’s syndrome, as well as in a cohort of patients whose status of having or not having Sjögren’s syndrome was difficult to determine.
Patients in all 3 groups shared certain key characteristics that made them eligible for criteria development, including having signs and/or symptoms suggestive of Sjögren’s syndrome that necessitate a comprehensive clinical evaluation. In addition to the symptom-associated data, objective tests were conducted that focused on oral, ocular, and systemic/serologic end points.
The new classification criteria performed well among the test cohorts, and maintained high sensitivity and specificity among patients with a difficult-to-determine Sjögren’s syndrome status.
Using the weighted sum of the objective tests, the working group determined that the final classification criteria and their respective weights are:
- Anti-SSA/Ro antibody positivity, 3
- A focal lymphocytic sialadenitis focus score of ≥1 foci/4 mm2, 3
- An abnormal ocular staining score of ≥5 or a van Bijsterveld score of ≥4, 1
- A Schirmer’s test result of ≤5 mm per 5 minutes, 1
- An unstimulated salivary flow rate of ≤0.1 mL per 1 minute, 1.
Patients exhibiting signs and/or symptoms of Sjögren’s syndrome who have a total score of ≥4 based on the weights assigned to these criteria items meet the standards for primary Sjögren’s syndrome.
Clinical ImplicationsThese criteria differ from those established by the ACR in 2012 in several ways. Improvements in the new classification criteria include the addition of unstimulated whole saliva flow rate and Schirmer’s test, having a van Bijsterveld score as an option when ocular staining scores are unattainable, and extending the threshold for ocular staining scores.
In addition, positive rheumatoid factor and high-titer antinuclear antibody have been removed from the list of criteria items.
In a nod to the recent changes to the landscape of Sjögren’s syndrome brought forth by the validation of disease activity indices and the availability of new drugs, the International Sjögren’s Syndrome Criteria Working Group asserts that these finalized, ACR/EULAR-approved criteria are appropriate for use in the enrollment process in clinical trials.
z