AxSpA is a chronic disease, which usually leads to functional limitations and has an important impact on participation in the labor force . Scholars point out that the increase in healthcare expenses related to axSpA patients in the public healthcare system is significant and noticeable [15, 16]. Besides the cost of medical care itself, the cost of productivity loss due to inefficiency in disease-related work, which accounts for 53–73% of total cost, also needs attention . In addition, the lack of patient self-management support also increases the cost of disease. The SpAMS can make real-world healthcare economically and offer patients a chance to self-manage their disease . The SpAMS is also a good tool for researchers to answer these questions about how disability affects workers, and what productivity is being lost due to disease relevant to broad populations of patients. In this study we determined that axial spondyloarthritis had a significant influence on working conditions in China in the real world. Beyond this we evaluated clinical characteristics and loss of work efficiency, finding that suffering from IBD and having higher ASAS HI scores are both predictive factors for work disability. Factors including disease activity, functionality, ASAS HI score, nocturnal pain, total back pain, and PGA were all related to the disease and had a significant correlation with work productivity.
1187 patients were included in our study. We found the employment rate in patients with axSpA in China is 66.81% is higher than the rate in England, which was 62% . The patients in our research were much younger than those in the English study. This rate is lower, however, than the rate of employment for patients with chronic low back pain and previously unrecognized axSpA in Netherlands; the employment rate in that instance was 72.2% . Patients with axSpA with income-earning jobs in China worked 3.5 hours/week more than axSpA patients in Italy . In Italy, the presenteeism is 23.53%, the absenteeism is 10.40%, and the WPL is 30.57%. A British study of 490 axSpA patients reported a 22% presenteeism and 23.2% WPL ,While data in the Dutch and Italian studies 33% presenteeism and 36% WPL were provided . The differences may be due to the average age, the disease duration, and factors specific to the country in question. The socioeconomic environment may also play an important role. Each study demonstrated that axSpA had a significant impact on work productivity.
We next evaluated which factors can predict the existence of work disability. Work disability was defined as people who were employed with work restrictions and unemployed due to work restrictions using patient-self assessment. For axSpA there are two major tools to assess disease activity, the BASDAI and the ASDAS, one for function, the BASFI, and several mobility measures including the BASMI. In our study, the above index cannot be used to predict the occurrence of the work disability. The ASAS HI, which measures functioning and health across 17 aspects of health and 9 environmental factors in patients with SpA, was used to evaluate the impact of SpA and its treatment on functioning and health . We found that ASAS HI and PhGA were the significant predictor of WD, with higher ASAS HI and PhGA scores indicating higher risk of WD by assessing functioning, disability, and overall health. One study found that ASAS HI could be used to represent the health status of SpA in a systematic way . Combined with our work, this indicates that the ASAS HI and PhGA should be regularly surveyed in employed patients with axSpA. We also found that IBD functioned as another WD predictor. A follow-up study found that newly developed IBD was associated with a higher disease activity score, worse physical function, and worse global patient well-being . Early recognition of IBD in patient with axSpA might prevent adverse work outcomes, more study should be researched.
The WPAI questionnaire offers important information about work productivity and daily activities. We investigated work productivity and daily activities and their relationships with demographic, clinical and extra-articular manifestations data, past medical history, disease activity, physical functioning, and mobility measures. Our study found that PGA, BASDAI, BASFI, ASAS HI, ASDAS, TOTAL BACK PAIN, and NOCTURNAL PAIN scores were moderately correlated with work productivity and daily activities, and the correlation coefficient was higher than ESR and CRP. As anticipated, we found that the BASFI is the most relevant to WPL in China. BASFI was used to assess the patient function; it was generally found that worse function led to worse work ability, so this index indicated the severity of work productivity loss. Presenteeism and WPL were both associated with higher disease activity [20, 25]. There is also a significant correlation between persistent high disease activity trajectories (higher ASDAS values) and work outcomes . We compared the loss of work productivity in patients with different disease activity (disease inactivity group, moderate activity group, high activity group, and extremely high activity group according to ASDAS score (which is assessed by a physician and is therefore more objective) at baseline in China. The loss of work productivity showed the most obvious differences between the disease activity and inactivity groups. We also found that the higher the disease activity, the worse physical function, mobility measures, and patient assessment were. This correlated with a greater loss of work productivity.
Non-steroidal anti-inflammatory drugs relieve inflammatory symptoms effectively and are presently the first line drug treatment . As anticipated, this functions as a protective factor and helped retain the ability to work. TNF inhibitors (TNFi) are also effective therapies for axSpA . Studies reported significant improvements in work disability after commencement of TNFi therapy [29, 30]. However, there was no correlation between TNFi used and loss of work ability in our study. The reasons were as follows: the study was an observational study, and long-term follow-up studies are needed in the future to observe the long-term work ability of patients with axSpA prognosis. Additional research should be done regarding TNFi, since the cost of the treatment means that fewer patients used it, reducing our sample size.
In this study, the SpAMS was used to collect clinical characteristics and work disability of patients with axSpA in China. We then assessed the status of work and work productivity impairment, as well as the related factors, to provide a clinical basis for the risk and severity of work disability. In the future, longitudinal research should be carried out. The process of disease and its relationship with work productivity will also be studied, so that we can fully explore the causes of adverse work outcomes in axSpA patients.