Background There has been much research aimed at elucidating key biological and clinical features which predict severity of disease and development of lymphoma in patients with primary Sjögren's syndrome (pSS). Key biological predictors identified include the presence of leukopenia or lymphopenia, hypocomplementaemia, cryoglobulinaemia, monoclonal gammopathy; key clinical predictors include younger age at time of symptom onset or diagnosis, peripheral neuropathy, salivary gland enlargement and skin involvement (particularly palpable purpura) [1–4]. The UK Primary Sjögren's Syndrome Registry (UKPSSR) is a MRC funded patient cohort, devised to facilitate research into pSS to improve understanding of the condition.
Objectives Ascertain the prevalence of putative clinical predictors amongst UKPSSR patients. Explore the relationship between demographics, clinical parameters, disease severity and lymphoma development.
Methods Patients were identified on the UKPSSR (n=868), those with insufficient data were excluded from analysis (n=36). Frequency of the predictors was calculated for remaining 832 patients. Patients were assigned a value for each predictor: 1 for present, 0 for absent. These values were then added to provide the prevalence of each predictor within the cohort, and a cumulative score for each patient. Each patient had 2 cumulative scores: one for disease severity and risk of death, the other for risk of lymphoma. Patients with a recorded age of pSS symptom onset (n=739) were analysed to investigate the relationship between age of onset and development of lymphoma. SPSS used for statistical analysis.
Results Pearson Chi-squared analysis found a statistically significant (p=0.004) increased incidence of lymphoma in patients presenting with symptoms of pSS before the age of 35. Predictors of lymphoma development were more common in patients whose symptoms started between age 20–34 (p=0.05). Patients with diagnosed lymphoma had a higher cumulative lymphoma risk score than patients who did not have lymphoma (p=0.05). Predictors of severe disease were found to be more common in patients whose symptoms began before age 35 (p=0.05).
Conclusions This analysis corroborates the findings of previous research showing an increased lymphoma prevalence in patients presenting with pSS at a younger age . It also finds a statistically significant link between poor prognostic features and development of lymphoma as described in the literature [2,3]. Further statistical analysis will aim to establish the link between each predictor and the development of systemic manifestations of pSS, baseline and cumulative ESSDAI scores and lymphoma.
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Disclosure of Interest None declared