An increase in disease activity during the early stages of axial spondyloarthritis (axSpA) is linked to a decline in physical health-related quality of life in patients over time, according to recent study.
Dutch researchers evaluated the link between disease activity and health-related quality of life (HRQOL) in patients with early axial spondyloarthritis (axSpA) by measuring and comparing how changes in Ankylosing Spondylitis Disease Activity Scores (ASDAS) correlate with HRQOL over time.
A total of 361 patients enrolled in the SPondyloArthritis Caught Early (SPACE) cohort, an ongoing study that includes patients older than 16 with chronic back pain, had their HRQOL determined through the Medical Outcomes Study Short-Form 36-Item Health Survey (SF-36).
The SF-36 is a clinical indicator of overall health status and consists of a set of generic, coherent, and easily administered quality-of-life measures. These measures rely upon patient self-reporting and are widely used by managed care organizations for routine monitoring and assessment of care outcomes in adult patients. It consists of eight scaled scores, of which lower scores indicate more disability.
The analysis focused specifically on the physical (PCS) and mental component summary (MCS) of the survey and included patient data at the beginning of the study and one year after enrollment.
Of the 361 patients, 107 either did not have an axSpA diagnosis, the diagnosis was missing, or they failed to fulfill the classification criteria after diagnosis. ASDAS could not be calculated in 12 patients, and one patient did not fill out the SF-36 survey.
Of the 161 patients with a definitive diagnosis of axSpA, 53 percent were male, and the mean age was about 30 years old.
The analysis revealed no changes in the MCS score, similar to that of the general population, the mean score of which is 50.
According to researchers, “no correlation was found between the change in ASDAS and the change in MCS,” and as such, the analysis was focused on patients’ physical health.
Results showed that increases in disease activity were associated with a decline in physical HRQOL over time — changes in a single unit in the ASDAS led to a decrease of 9.5 points in the physical component summary of the SF-36.
Researchers found that the association between ASDAS and the physical component summary changed according to two specific variables: gender and job type. The same level of disease activity had fewer adverse effects on the physical HRQOL in women and white-collar workers, those who perform their jobs in an office or other administrative setting.
“To our knowledge, our data are the first to show that in a broad group of patients with early axSpA, increasing ASDAS is associated with worsening of physical HRQOL, but not mental HRQOL, over time,” the researchers wrote, adding that this finding “supports the recommendation that in patients with early axSpA, inactive disease or low disease activity should be the treatment target.”