THU0693 INPATIENT PREVALENCE, EXPENDITURES AND COMORBIDITIES OF TAKAYASU’S ARTERITIS: A PROPENSITY-MATCHED COHORT STUDY

Abstract

Background Takayasu’s arteritis (TAK) was first described in Japan. Since then, the disease has been extensively studied in Japan and other Asian countries [1]. However, little is known about the characteristics, inpatient burden, expenditures and comorbidities of TAK in the United States (US). Objectives To investigate the inpatient prevalence, expenditures and comorbidities of patients with TAK in the US. Methods Patients with TAK were identified within the Nationwide Inpatient Sample (NIS) database of the years 2013-2014 using ICD-9 diagnostic code. NIS is a publicly available inpatient database that contained data of over 7 million hospital stays, which are a 20% stratified sample of over 4,000 non-federal acute care hospitals from more than 40 states of the US. Data on patient characteristics, comorbidities, resource utilization and expenditures was collected. A propensity-matched cohort of patients without TAK was also created from the same database to serve as comparators for the analysis of comorbidities. Inpateint prevalence of TAK was calculated using all admissions in the NIS database as denominator. Odds ratios (OR) comapring the prevalence of comorbities between cases with TAK and propensity-matched controls without TAK were calculated. Results A total of 2,840 patients with TAK were identified from the database, corresponding to an inpatient prevalence of 4.6 cases per 100,000 admissions. The 5 main reasons for admission in patients with TAK were as follows; chest pain (17%), acute myocardial infarction (16%), stroke (14%), sepsis (14%) and pneumonia (11%). Compared to the propensity-matched cohort of patients without TAK, patients with TAK were found to have significantly increased odds of stroke, aortic aneurysm, aortic valvulopathy and peripheral vascular disease. TAK was also associated with increased use of some procedures (Table 1). However, the mortality was not significantly different (adjusted OR: 1.44, 95% CI: 0.58 – 3.61, p=0.43). After adjusting for confounders, patients with TAK displayed a mean additional $11,275 (95% CI, $4,946 - $17,603) for total hospital costs (the amount of money invested by each institution in providing patient care) and a mean additional $45,305 (95% CI, $23,063 – $67,546) for total hospitalization charges (the amount of money that each hospital billed for providing its service on each case) when compared to patients without TAK. Conclusion The inpatient prevalence of TAK was higher than what would be expected from the overall incidence. The mean total hospital costs and total hospitalization charges for patients with TAK were higher than patients without TAK. Analysis of comorbidities found significantly higher odds of several vascular comorbidities compared to a propensity-matched cohort of patients without TAK.