Background/Purpose:   Healthy family members of patients with systemic autoimmune rheumatic diseases (SARDs) are at higher risk of developing autoimmune disease than the general population.  It is postulated that serological changes precede the onset of clinical autoimmune disease in affected individuals.  Our aim is to determine if these serological changes are present in the relatives of patients with SARD, and if so, whether they can be used to predict the development of  autoimmune disease.  This would permit introduction of treatment early in the disease course thereby preventing damage.  We have previously obtained blood for serologic testing and performed a cellular analysis on the first-degree relatives of patients with systemic lupus erythematosus.  At the time of blood draw, a questionnaire was administered seeking evidence of autoimmune disease.  In total 893 medical histories were obtained via questionnaire, with 178 reporting an autoimmune disease.   However, less than 50% were able to be confirmed as accurate (Cooper et al, J Rheumatol. 2008 35 (10): 2001-4).  In this study, we developed a validated questionnaire that more accurately reflects the presence of autoimmune disease, that can be used for a follow-up of the first-degree relatives of patients with SARDs.

Methods:   A questionnaire was developed in consultation with an expert for distribution to patients for validation.  In contrast to our previous questionnaire it incorporates questions that have been developed to confirm the presence of disease through questions regarding specific clinical manifestions of disease and/or treatment.  After obtaining informed consent, the questionnaire was administered to patients with each autoimmune disease of interest, with those having other autoimmune diseases or osteoarthritis serving as controls.  Accuracy at identifying the presence or absence of a particular autoimmune disease was confirmed against data from patients’ medical records.  False positive (FP) and false negative (FN) rates were compared for each autoimmune disease.

Results:   63 patients were consented and completed the questionnaire, including at least 5 patients with each autoimmune disease of interest.   Results are shown below:

Comparison of Accuracy of Original Questionnaire (Cooper et al) and New Questionnaire

There were no FP results in the general screening questions of both SLE and Type 1 DM.  In those SARDs that had FP responses to the original screening question, accuracy was was improved in many by the confirmatory questions.  In general FN rates were low.

Conclusion:   The new questionnaire improved overall accuracy over our original questionniare in screening for most autoimmune diseases and can be used to more accurately identify family members with these conditions.