Predicting adverse outcomes in primary Sjogren's syndrome: identification of prognostic factors.
OBJECTIVE
To identify features present at diagnosis that were prospectively associated with adverse outcomes in a large cohort of patients with primary Sjögren's syndrome (SS).


METHODS
Two hundred and sixty-six patients diagnosed with primary SS in our department between 1984 and 2002 were consecutively included and followed up. Outcomes measured were vasculitis, B-cell lymphoma and death. Cox regression analysis was used to evaluate the effect of variables at diagnosis on outcomes.


RESULTS
Twenty-five (9%) patients developed vasculitis. Multivariate analysis identified parotid scintigraphy grades III or IV (HR 3.55, P = 0.05) and C4 levels <0.11 g/l (HR 8.26, P < 0.001) as variables predicting the development of vasculitis. Nine (3%) patients developed B-cell lymphoma. Multivariate analysis identified C3 levels <0.82 g/l (HR 7.54, P = 0.016) as a predictive factor of lymphoma development. Twenty-five (9%) patients died during follow-up. Systemic involvement (HR 4.51, P = 0.022), vasculitis (HR 4.58, P = 0.042), C4 levels <0.11 g/l (HR 5.47, P = 0.027) and cryoglobulins (HR 4.58, P = 0.013) were independently associated with death. The presence of at least two of the above-mentioned predictive factors (parotid scintigraphy, vasculitis, hypocomplementaemia and cryoglobulinaemia) was associated with a lower survival in comparison with patients with no factor (log rank and Breslow tests <0.001).


CONCLUSIONS
The main prognostic factors for an adverse outcome identified in our cohort of patients with primary SS were vasculitis, severe involvement in parotid scintigraphy, hypocomplementaemia and/or cryoglobulins at diagnosis. Patients with at least two of these factors need a closer follow-up.
Brito-Zerón
P
P
Department of Autoimmune Diseases, School of Medicine, University of Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Barcelona, Spain.
Ramos-Casals
M
M
Bove
A
A
Sentis
J
J
Font
J
J
D000368:Aged; D003176:Complement C3 / Q000172:deficiency; D003181:Complement C4 / Q000172:deficiency; D003449:Cryoglobulinemia / Q000209:etiology; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D016393:Lymphoma, B-Cell / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000000981:diagnostic imaging; D011379:Prognosis; D011877:Radionuclide Imaging; D012720:Severity of Illness Index; D012859:Sjogren's Syndrome / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014657:Vasculitis / Q000209:etiology
D003176:Complement C3; D003181:Complement C4