P005 The economic burden of delayed diagnosis in axial spondyloarthritis in the UK
Authors: Zanghelini Fernando , Xydopoulos Georgios , Wilsher Stephanie H , Afolabi Oyewumi , Webb Dale , Eddison Joe , Gaffney Karl , Fordham Richard 
Published: December 2024

Abstract

Introduction
Timely diagnosis of axial spondyloarthritis (axSpA) remains challenging and delays result in harmful consequences. Few studies have evaluated the cost of delayed axSpA diagnosis. This study aims to develop an economic analysis to determine the annual cost of delaying the axSpA diagnosis, adopting both NHS (UK) and societal perspectives.

Methods
We developed a Markov economic model to estimate the costs of delayed axSpA diagnosis in the UK. The cohort of patients assessed comprised a mixed population (cohort size: 1,000 patients, 64% males), mean age of symptom onset 26 years. The model captured the resources used and costs related to diagnosing and managing axSpA symptoms until the disease was diagnosed.

Results
Results are summarised in Table 1. Our economic analysis results show the cost of delayed axSpA diagnosis is substantial and falls mainly on the individuals concerned in the form of productivity losses, out of pocket medical expenses, non-prescribed drug expenses, and travel costs to healthcare services. These costs are higher in younger patients but remain substantial in older groups. With a symptom onset at the age of 26 and an average time to diagnosis of 8.5 years, we estimate that the cumulative cost of delayed diagnosis per person living with axial SpA is £193,512 (CI95%: £108,769 - £306,789). The total annual cost that accrues to delay before the diagnosis of axSpA in the UK was £3.1 billion and £12.4 billion, based on a prevalence of 0.3% and 1.2%, respectively (Table 1). Our results corroborate findings from other studies, showing that patients with a late diagnosis of axSpA had higher costs, reduced incapacity for work, and worse clinical outcomes1,2. P005 Table 1.Nationwide total cost of delaying the axSpA diagnosis based on axSpA prevalence.Prevalence of 0.3%Prevalence of 1.2%ResultsTotal cost - ModelledTotal cost – NASS pop*Total cost – UK adult pop**Total cost – UK adult pop**DSA£23,104.17£4,236,794,775£3,115,805,703£12,463,222,813PSA£24,025.06£4,431,645,007£3,259,101,637£13,036,406,54995% LCI£14,568.52£2,703,455,437£1,988,163,769£7,952,655,07995% UCI£36,950.02£6,595,614,347£4,850,518,822£19,402,075,288Note: 83.4% remaining undiagnosed per year*NASS estimate population: 220,000 patients.**UK adult population (2022): 53,930,490.DSA: deterministic sensitivity analysis, LCI: low confidence interval, pop: population, PSA: probabilistic sensitivity analysis: UCI: upper confidence interval.

Conclusion
To our knowledge, this is the first UK-specific study and the first internationally to develop an economic analysis to determine the annual cost of delay in diagnosing axSpA, adopting both NHS and societal perspectives. Earlier diagnosis is essential in order to reduce healthcare needs, resource utilisation, and enhance the quality of life for people living with axSpA

References
1. Kobelt G, et al. Value Health. 2008 May;11(3):408–15.
2. Grigg SE, et al. ACRARHP Sci Meet 2011. 2011;63(abstract 1308).