Factor Analysis of the Clinical Characteristics of Primary Sjogren Syndrome

Purpose. The purpose of this study was to use factor analysis to analyze 90 clinical characteristics of a cohort of 231 patients with primary Sjogren syndrome (pSS). Methods. The records of all patients seen at the University Health Network Sjogren Syndrome Clinic from October 1992 to July 2006 were reviewed and documented. Those diagnosed as pSS by the American European Consensus Criteria of 2002 were included. The 90 clinical variables, including health history, blood analysis, symptoms of dry eye and dry mouth, salivary flow and biopsy, tear flow and staining, were analyzed by factor analysis. Results. Two hundred thirty-one patients with pSS charts were reviewed, and 90 variables were recorded. Factor analysis resulted in three factors: factor 1: ocular surface staining, factor 2: antimicrosomal antibodies and antithyroid antibodies, and factor 3: serum anti-Ro and anti-La. Conclusions. Ocular surface staining accounted for the greatest variance in this population of patients with pSS. (Optom Vis Sci 2010;87:742-750)