Defining and managing flares in axial spondyloarthritis

Flares correspond to fluctuations in disease activity or symptoms. They should be avoided in chronic inflammatory diseases. In axial spondyloarthritis (axSpA), work is ongoing to better conceptualise and treat flares. This review highlights recent data on the definition and management of flares in axSpA.

Many definitions of flares have been used in clinical trials, limiting the interpretation and comparison of studies. The expert group Assessment of SpondyloArthritis International Society (ASAS) developed a data-driven definition of flares/disease worsening: an increase in Ankylosing Spondylitis Disease Activity Score-C-reactive protein (ASDAS-CRP) of at least 0.9 points, for use in axSpA clinical trials. Flares are more challenging to define in clinical practice because of their multifaceted nature. Qualitative studies have shown that flares from the patient's perspective are related not only to disease activity, but also to fatigue, mood, sleep and general well-being. The management of axSpA relies on a treat-to-target (T2T) strategy and aims at reaching clinical remission while monitoring closely disease activity to prevent and shorten flares.

The concept of flares has been clarified, and definitions have been developed for use in trials. The T2T approach aims at minimising flares in axSpA. The early recognition of flares and their severity may lead to better management.