The direct healthcare costs associated with ankylosing spondylitis patients attending a UK secondary care rheumatology unit

Objectives. To explore the direct healthcare resources associated with ankylosing spondylitis (AS) in the UK. A secondary objective was to establish if resources, and thus healthcare costs, vary by disease severity. Methods. Medical records of 147 sequential AS patients attending a UK secondary care rheumatology unit were examined to assess the direct healthcare resources used over the previous 12 months. Starting with a detailed inventory and measurement of resources consumed, unit cost multipliers were applied to the quantity of each type of resource consumed. The mean cost per patient was estimated using the total cost divided by the number of patients included. Results. The mean (median) annual cost per patient was 1852 pound (892) pound. The distribution of cost data was skewed, with 11% of patients incurring 50% of the total costs. The three most relevant cost domains were physiotherapy, hospitalization and medication costs at 32, 21 and 20% of the total costs, respectively. Twenty percent of the patients received physiotherapy, 13% received inpatient care and almost all incurred medication costs. Thirty-four percent of patients were prescribed disease-modifying anti-rheumatic drugs and 85% non-steroidal anti-inflammatory drugs. Over 50% of patients had at least one comorbidity. Conclusion. Direct costs accelerate steeply with disease activity (Bath Ankylosing Spondylitis Disease Activity Index > 6.0) and increasing loss of function (Bath Ankylosing Spondylitis Functional Index > 6.0) in patients with AS. The most severely affected patients incur 50% of the total costs, and physiotherapy accounts for 32% of the total healthcare costs in the UK.