Hydroxychloroquine is associated with a lower risk of polyautoimmunity: data from the RELESSER Registry.

Objectives: This article estimates the frequency of polyautoimmunity and associated factors in a large retrospective cohort of patients with SLE.

Methods: RELESSER (Spanish Society of Rheumatology Lupus Registry) is a nationwide multicentre, hospital-based registry of SLE patients. This is a cross-sectional study.