The importance of quality of life for work outcomes in patients with ankylosing spondylitis - a cross-sectional study

Aims: Work impairment is one of the most important exploration and one of the aims of rheumatologists. We aimed to determine the risk factors for employment state and predictive factors of work outcomes using multi-dimensional measures in patients with ankylosing spondylitis (AS) in this comprehensive study. Methods: One hundred patients with AS (31 females and 69 males) were included into this study. Demographic properties, local factors, disease activity (BASDAI), functionality (BASFI), spinal mobility (BASMI), radiologic stage (BASRI), quality of life (AS-QoL), cardiopulmonary involvement, exercise stress test and work outcomes were investigated and compared in employed and un-employed patients. The work instability scale (AS-WIS) and work productivity activity impairment scale (WPAI:SpA) were selected as work outcomes. The predictive factors were analyzed using multiple stepwise linear regressions. Major results: Thirty-two patients (mean age: 42,6±11.7) were unemployed and the risk factors for unemployment state were female sex, lower annual income level, and older age. Work disability was detected only in 5% of patients. Decreased chest mobility (beta: -0.398, p: <0.001), low annual income level (beta:-0.291, p:<0.001), higher co-morbidities (beta:0.237, p:0.004), poorer AS-QoL (beta:0.238, p:0,012) and poorer AS-WIS score (beta:0.289, p: 0,004) were the predictors of work impairment. The predictive factors for work instability were higher work impairment (beta:0.533, p<0.001) and poorer AS-QoL (beta: 0.426, p<0.001) scores. Conclusions: Employment state mainly depends on contextual factors including male sex, higher income, and younger age. Socioeconomic factors as well as clinical data such as QoL were predictive for work productivity. Poorer AS-QoL was also a predictive factor for work instability.We suggested effective interventions to improve clinical and economic status in patients with AS.