Understanding flare in axial spondyloarthritis: novel insights from daily self-reported flare experience

The natural history of chronic widespread pain in patients with axial spondyloarthritis: a cohort study with clinical and self-tracking data

OBJECTIVES

This study investigates longitudinal patterns, predictors and long-term impact of pain in axial spondyloarthritis (axSpA), using clinical and self-tracking data.

METHODS

The presence of multisite pain (MSP), affecting at least six of nine body regions using a Margolis pain drawing, and subsequent chronic widespread pain (CWP), MSP at more than one timepoint, was assessed in a cohort of axSpA patients. Incident MSP (MSP at two consecutive visits or more), intermittent MSP (MSP at two or more non-consecutive visits) and persistent MSP (MSP at each visit) were described. Demographic, clinical and self-tracking measures were compared for the CWP vs non-CWP groups using Students t test, Wilcoxon-Mann-Whitney and χ2 test for normal, non-normal and categorical data, respectively. Predictors of CWP were evaluated using logistic regression modelling.

RESULTS

A total of 136 patients, mean clinical study duration of 120 weeks (range 27-277 weeks) were included, with sufficient self-tracking data in 97 patients. Sixty-eight (50%) patients reported MSP during at least one clinical visit: eight (6%) incident MSP; 16 (12%) persistent MSP; and 44 (32%) intermittent MSP. Forty-six (34%) of the cohort had CWP. All baseline measures of disease activity, function, quality of life, sleep disturbance, fatigue and overall activity impairment were significant predictors of the development of CWP. BASDAI and BASFI scores were significantly higher in those with CWP and self-tracking data revealed significantly worse pain, fatigue, sleep quality and stress.

CONCLUSIONS

The development of CWP is predicted by higher levels of disease activity and burden at baseline. It also impacts future disease activity and wellbeing.

Defining and managing flares in axial spondyloarthritis

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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.

SUMMARY

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.