FRI0085 Prediciting rheumatoid arthritis by autoantibody testing (PRERA): Preliminary results of a community-based investigation

Background A characteristic feature of RA is the presence of autoantibodies (AAB) such as rheumatoid factor (RF), anti-RA33, and antibodies to citrullinated peptides (ACPA) in a majority of patients. RF and ACPA are not only diagnostically helpful but are also prognostic indicators for progression of joint destruction. Over the past years, health care research has increasingly focused on early diagnosis and even prevention. Since RA is a disease of significant morbidity, affecting app. 0,5 - 1% of the population and leading to progressive disability as well as individual and societal costs, pre-emptive recognition of the disease or at least of a high risk to develop RA could help for planning optimal therapeutic measures. Objectives Given that certain AAB are highly specific for RA and may precede the disease by many years, antibody testing in healthy individuals could prove helpful for evaluation of the risk to develop RA and for designing innovative therapeutic strategies that attempt to interfere with the disease process at a very early time point. In this prospective study we determined AAB in healthy individuals presenting to community health centres for pre-emptive health screening to investigate the prevalence of ACPA, RF, and anti-RA33 in the population and to subsequently determine the incidence of RA in AAB-positive individuals compared to AAB-negative persons over a period of five years. Methods Blood drawn at the time of the screening examination was anonymously analyzed for the presence of AAB. All AAB positive individuals as well as age and sex matched AAB negative persons were invited to attend the outpatient clinic for a thorough rheumatological examination and follow-up. Results 3059 Sera were obtained over a period of 22 months; 178 (5,8%) were positive: 95 (3,1%) for RF, 82 (2,6%) for ACPA, and 4 (0.1%) were positive for both AAB; among the RF positive individuals, almost 21% (0,6% of the total population) had high titer RF (>50IU/ml). Among the patients who subsequently attended a rheumatological examination, none had signs of inflammatory joint disease; however, none of the participants of this ongoing study has been followed for more than 18 months. Conclusions Among healthy individuals, there is a prevalence of AAB of 5,8%. 0,6% of the total population with high titer RF and 0.8% ACPA with little overlap of RF and ACPA. None of these persons had evidence of an inflammatory joint disease. Follow up examinations will reveal the potenti