LAS VEGAS – Patients with Sjögren’s syndrome do not have an increased prevalence of hand osteoarthritis, but they are strongly predisposed to have a history of hypothyroidism, Jeremie Sellam, MD, reported at the World Congress on Osteoarthritis.
Both of these findings in his small case-control study were unexpected, he added at the congress sponsored by the Osteoarthritis Research Society International.
Bruce Jancin/Frontline Medical News
Dr. Jeremie Sellam
The study included 34 women with primary Sjögren’s syndrome according to the 2002 American-European Consensus Group criteria and 54 female controls with sicca syndrome but no autoantibodies and no Sjögren’s syndrome. All subjects were evaluated at a specialized tertiary Sjögren’s syndrome clinic. The controls were referred there to ascertain whether they had Sjögren’s syndrome.
Among the Sjögren’s syndrome patients, 41% had radiographic evidence of hand osteoarthritis, 12% had symptomatic hand osteoarthritis, and 9% had erosive hand osteoarthritis. In the sicca syndrome–only patients, the rates were similar at 52%, 28%, and 9%, respectively.
Looking for commonalities and differences between the Sjögren’s syndrome patients and controls, Dr. Sellam and his coinvestigators noted that the Sjögren’s syndrome patients were significantly older, with an average age of 64 years, compared with 48.5 years in the controls.
Impressively, two-thirds of the 15 Sjögren’s syndrome patients with hand osteoarthritis had a history of hypothyroidism, compared with just 15% of the 27 non-autoimmune sicca syndrome patients with hand osteoarthritis and one-quarter of the Sjögren’s syndrome patients without hand osteoarthritis. This suggests a possible interaction between Sjögren’s syndrome, hand osteoarthritis, and a history of hypothyroidism which merits further study, according to the rheumatologist.
Because of the relatively small patient numbers in the French study, Dr. Sellam and coworkers ran a crosscheck with data from the Framingham Osteoarthritis Study and found hand osteoarthritis prevalence rates comparable to their own findings. For example, the prevalences of radiographic and erosive hand osteoarthritis in the French Sjögren’s syndrome and non-autoimmune sicca syndrome groups were similar to the 44% and 10% figures, respectively, in the general population of age-matched Framingham women (Ann Rheum Dis. 2011 Sep;70[9]:1581-6).
He reported having no financial conflicts regarding his study, which was conducted free of commercial support.