Construction of a questionnaire to characterize environmental exposures in patients with systemic lupus erythematosus

Abstract

IntroductionAs the knowledge of systemic lupus erythematosus (SLE) advances, the need to characterize the burden of environmental exposure in patients becomes increasingly relevant. However, there is currently no tool validated to measure such exposure. For this reason, the objective of this work was the construction of a questionnaire-type tool, in order to detail the exposure to multiple environmental factors previously associated with SLE. MethodsThe literature was reviewed to identify relevant environmental factors associated with SLE, and the first version of the questionnaire was constructed. After expert review and feedback, the questionnaire was consolidated and applied to 40 patients and 20 healthy controls. Finally, exploratory Rasch analysis was performed to determine the performance of the tool’s response function. ResultsThe tool showed a favorable performance in the exploratory analysis of its psychometric properties. Additionally, it allowed the characterization of 10 environmental factors and the differences in the frequencies of exposure between patients with SLE and healthy controls. A high co-occurrence of exposures was identified, as most of the patients had positive exposures to three or more factors simultaneously. ConclusionA practical and easy-to-apply tool has been constructed, with a favorable performance in its psychometric properties. To our knowledge, this is the first tool in the Spanish language for the characterisation of multiple environmental exposures, and constructed explicitly for patients with SLE with a validation analysis. It enabled us to identify that most of the lupus patients were exposed to the sum of three or more environmental factors.