Patients with ankylosing spondylitis face long, frequent flares
Flares are common and long in patients with ankylosing spondylitis (AS) before the wide use of biologics, according to a Canada study.
To examine the frequency of patient-reported flares and their related factors, researchers conducted a cross-sectional study using 2004 data of a Canadian cohort with AS according to the modified New York criteria (n=234; mean age 45.5 years; 73.5 percent males).
They assessed the participants’ current flare status (“Are you experiencing a current flare?”), number of flares over the past 3 months, average duration, Bath Ankylosing Spondylitis Disease Activity and Functional Index (BASDAI and BASFI, respectively), and AS Quality of Life questionnaire by self-report. Factors linked to current flare were analysed using univariate and multivariate regressions.
AS patients had a mean disease duration of 21.7 years, and mean BASDAI and BASFI (0 to 10) of 4.4 and 3.4, respectively. There were 18 (7.7 percent) patients who received antitumour necrosis factor (anti-TNF).
Of the analysed patients, 175 (74.8 percent) reported flares and 117 (50 percent) were currently in flare. Those who reported flares had a median of three occurrences in 3 months, with a median duration of 2 weeks. As a whole, all 234 patients spent a median of 25 percent of their time in flare.
Based on multivariate analyses, current flare was significantly associated with higher BASDAI (odds ratio [OR], 2.01; p=0.01), worse quality of life (OR, 1.37; p=0.004), shorter AS duration (OR, 1.19; p=0.04) and less anti-TNF (OR, 7.14; p=0.03).
“As expected, flare was associated with higher disease activity, suggesting the validity of the concept of patient-reported flares,” researchers said.