Demographic and clinical differences between ankylosing spondylitis and non-radiographic axial spondyloarthritis: results from a multicentre retrospective study in the Lazio region of Italy

Maria Sole Chimenti, Paola Conigliaro, Luca Navarini, Francesca Maria Martina, Giusy Peluso, Domenico Birra, Paola Sessa, Michele Anzidei, Palma Scolieri, Vincenzo Bruzzese, Gianluca Santoboni, Paolo Cardello, Elisa Gremese, Antonella Afeltra, Guido Valesini, Gian Domenico Sebastiani, Roberto Perricone, Rossana Scrivo