Background/Purpose: To examine the economic burden, demographic and clinical characteristics of ankylosing spondylitis (AS) in the U.S. veteran population.

Methods:   A retrospective database analysis was performed using the Veterans Health Administration (VHA) Medical SAS Datasets from October 1, 2007 to September 30, 2011. Patients with AS were identified using International Classification of Disease 9^th Revision Clinical Modification (ICD-9-CM) diagnosis code 720.0x. Survival was determined with the PROC LIFETEST procedure, and descriptive statistics were calculated as means ± standard deviation (SD) and percentages to measure demographics, costs and utilization distribution in the sample. 

Results:   In patients identified with AS (n=2,455),  total survival rates in the 12-month follow-up period were 98.1% for patients  age ≤39, 97.0% for those age 40-64, and 89.6% for those age ≥65. The most common comorbidities in AS patients were hypertension (62.77%), any tumor or malignancy (25.50%), and diabetes (24.11%). The percentage of patients who had follow-up inpatient visits was 14.34%, which translated into $6,240 in inpatient costs per patient. The percentage of patients who had follow-up outpatient visits was 99.88%, which translated into $6,838 outpatient costs per patient. The average number of inpatient (0.25, SD=0.79), emergency room (ER) (0.10, SD=0.58), physician office (15.99, SD=16.63) and outpatient visits (17.54, SD=17.88) were also calculated for AS patients.

Conclusion:   Comorbidities may play an important role in the costs of AS treatment, since more than 20% of the study population was also diagnosed with any combination of hypertension, diabetes, and tumor or malignancy.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/assessing-the-clinical-and-economic-burden-of-u-s-veteran-ankylosing-spondylitis-patients/