Salivary gland abnormalities in primary Sjögren’s become more serious over time, research shows

New research at ACR Convergence 2023, the annual meeting of the American College of Rheumatology (ACR), shows that ultrasound-detected salivary gland abnormalities in primary Sjögren’s become more severe over time and that the slowly progressive disease likely begins long before it reaches the is first. detected (summary #1371).

Sjögren’s disease, also called primary Sjögren’s syndrome, is a systemic autoimmune disease. It is characterized by inflammation of the tear and salivary glands, leading to chronic dry eyes and mouth. Fatigue is common and about a third of patients have complications affecting the lungs, skin, kidneys and joints. Up to 60% of patients may develop systemic symptoms.

Salivary gland ultrasound (SGUS) is a safe and non-invasive method for diagnosing and monitoring Sjögren’s disease. Still, it’s unclear whether the abnormalities it detects become more notable over time. Valérie Devauchelle-Pensec, M.D., Ph.D., professor of rheumatology in the Department of Clinical Immunology and Rheumatology at the University of Brest Occidentale and Cavale Blanche Hospital in Brest, France, designed a cross-sectional international study to find out.

 

I have been caring for patients with Sjögren’s disease for years and I am always surprised that when I see them at the beginning of their disease, their first ultrasound scan of the salivary gland shows severe lesions. I also have many patients with rheumatoid arthritis. In rheumatoid arthritis, the joints are destroyed, but not at the onset of the disease. Sjögren’s seems different. I wondered, ‘When does the disease really start and do the lesions evolve over time or not?’ Many of my colleagues, who are experts in Sjögren’s and ultrasound, agreed to participate [in the study].”

 

Valérie Devauchelle-Pensec, MD, Ph.D., professor of rheumatology, department of clinical immunology and rheumatology at the University of Brest Occidentale

 

Between May 2019 and February 2022, 247 patients from 11 international centers consecutively participated in the study. Most were women, with an average age of 58 years. Nearly 100% of patients reported dry mouth; 75% had abnormal saliva production and 85% were positive for anti-SSA autoantibodies, a hallmark of Sjögren’s. The median EULAR Sjögren’s disease activity score (ESSDAI) was 3, indicating low disease activity.

Ultrasound-detected functional abnormalities of the parotid and submandibular gland were classified according to the most recent Outcome Measures in Rheumatology (OMERACT) score, a four-grade semiquantitative scoring system. The patients were then grouped according to the duration of illness from the onset of dry mouth symptoms.

• • Group A: less than five years (47 patients)

• • Group B: five to nine years (69 patients)

• • Group C: 10 to 20 years (78 patients)

• • Group D: More than 20 years (53 patients)

When the researchers looked at the most serious node for each patient, they found a significant association between disease duration and the OMERACT score. The odds ratio for progression over a five-year interval was 1.23.

There was no statistical difference between the groups with regard to the various ultrasound parameters, with the exception of the proportion of hyperechoic bands, which are associated with damage in established Sjögren’s patients.

“We hypothesized that hyperechoic bands represent the slow fibroadipose evolution of the disease,” says Devauchelle-Pensec. “To me, this means that Sjögren’s disease starts long before we find it, so it is important to treat patients early.”

She adds that the study highlights the importance of adding ultrasound findings to the classification criteria for Sjögren’s syndrome and the need for a better understanding of when the disease begins.