POS0211-HPR REDUCED SLEEP QUALITY IS HIGHLY PREVALENT AND ASSOCIATED WITH PHYSICAL FUNCTION AND CARDIORESPIRATORY FITNESS IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS

Abstract

BackgroundSleep is an important aspect of health for patients with axial spondyloarthritis (axSpA)[1], and it is therefore essential to identify modifiable factors related to reduced sleep quality.ObjectivesTo assess sleep quality and the associations between sleep quality and physical function, cardiorespiratory fitness and spinal mobility in patients with axSpA.MethodsIn this cross-sectional study, baseline data from the ESpA trial[2]was used. The assessments included sleep quality (Pittsburg Sleep Quality Index, PSQI) assessing 7 aspects of sleep quality (each scored 0-3, ≥2 reduced sleep quality), summed into a global score (0-21, 21=worst), performance-based physical function (Ankylosing Spondylitis (AS) Performance Index, ASPI; time), patient-reported physical function (Bath AS Functional Index, BASFI; 0-10, 10=worst), cardiorespiratory fitness (VO2peak, ml/kg/min) and spinal mobility (Bath AS Metrology Index, BASMI; 0-10, 10=worst). Associations between PSQI (global score) and ASPI, BASFI, V02peak and BASMI were examined in separate models using linear regression analyses, controlling for age and sex.ResultsA total of 99 patients with axSpA were included, 55% male, mean age 46 years and 72% with high disease activity (ASDAS >2.1). Reduced sleep quality (PSQI global score >5) was found in 85% of the patients. The most frequently affected aspect was sleep disturbances (65%) followed by poor subjective sleep quality (53%), daytime dysfunction (41%) and increased sleep latency (41%) (figure 1). Adjusted for age and sex, statistically significant associations were observed between PSQI and ASPI (β=0.10, 95% CI=0.01, 0.19) and BASFI (β=0.85, 95% CI=0.51,1.20) and an inverse association between PSQI and VO2peak (β= -0.14, 95% CI=-0.27, -0.01) (table 1), indicating that better sleep quality is associated with better performance-based and patient-reported physical function and higher cardiorespiratory fitness. There was no association between PSQI and BASMI.ConclusionReduced sleep quality is highly prevalent in patients with axSpA, with disrupted sleep most frequently reported. Better sleep quality was associated with better physical function and higher cardiorespiratory fitness, but there was no association with spinal mobility. The results signify physical function and cardiorespiratory fitness as modifiable factors that are independently associated with sleep quality in patients with axSpA.