FRI0425 Longitudinal analysis of direct medical costs for systemic lupus erythematosus in british columbia, canada: A population-based study
Authors: J.A. Avina-Zubieta, N. McCormick, E.C. Sayre, M. Sadatsafavi, J.M. Esdaile, C. Marra
Journal: Annals of the Rheumatic Diseases (2013)

<h3>Background</h3> Systemic lupus erythematosus (SLE) is a rare and chronic disease with high health care resource utilization due to disease activity as well as comorbidities secondary to the disease itself or the treatments to manage the disease. Direct medical costs are traditionally assessed in selective groups of selected cases and based on short periods of time. <h3>Objectives</h3> To estimate the direct medical costs in a population-based cohort of systemic lupus erythematosus (SLE) from the province of British Columbia (BC), Canada. <h3>Methods</h3> <i>Data sources:</i> Universal insurance coverage is a feature of BC's health care system and allows for the capture of administrative data of <i>all</i> health services (outpatient visits,investigations and hospitalizations) and <i>all</i> dispensed medications from 1996 through 2007 (regardless of funding source). <i>Study population:</i> A population-based cohort of SLE cases was identified using the following algorithm: 1 ICD code for SLE by rheumatologist or hospital, or 2 ICD codes for SLE at least 2 months and no more than 2 years apart by a non-rheumatologist. To improve specificity, we excluded individuals with at least 2 visits ≥2 months apart subsequent to the SLE daignostic visit with diagnoses of other non-SLE inflammatory diseases (rheumatoid arthritis, psoriatic arthritis, spondyloarthropathy, systemic vasculitis and other non-SLE connective tissue) and those where a diagnosis of SLE by a non-rheumatologist was unconfirmed later by a rheumatologist. <i>Cost calculation:</i> Costs for medical services and prescriptions were summed directly from paid claims. Case-mix methodology was used for hospitalizations. Costs are reported in inflation-adjusted 2007 Canadian dollars. <h3>Results</h3> We identified 5,002 SLE cases contributing 22,614 patient-years. <i>Direct medical costs</i> over 12 years accounted for <i>$181,193,220</i> ($25,369,618 in 2007) with <i>$50,982,215</i> (28%) from <i>outpatient costs</i> (MD visits, procedures and investigations). Although <i>hospitalizations</i> comprised only 2% of health encounters, at <i>$90,326,883</i> they represented 50% of the costs. Cost for <i>medications</i> was <i>$39,884,122</i> (22%). After inflation adjustments, annual overall mean per person year (PY) costs decreased by <i>28%</i> over 12 years, from $9,622 to $6,911 per PY. Outpatient encounters and costs decreased by <i>21%</i> (from 38 to 30 per PY) and <i>30%</i> ($2,631 to $1,850 per PY), respectively. Mean annual hospital costs decreased by <i>45%</i> (from $5,758 to $3,186 per PY) and admissions by <i>46%</i> (0.95-0.51 per PY) over 12 years. However, the mean annual dispensed prescriptions increased by <i>40%</i> (from 25 to 35 per PY), and their costs by <i>52%</i>, from $1,233 to $1,875 per PY. <h3>Conclusions</h3> These long-term reductions in per PY health care costs are encouraging and suggestive of increasingly efficient health service delivery. However, medications are a growing factor (by 4% annually, on-average) in the direct medical costs of SLE. As comorbidity burdens rise and demand grows for expensive but potentially-better SLE therapies, research to assess the impact of new therapies on comorbidity risk should be considered to determine their relative value. <h3>Disclosure of Interest</h3> J. A. Avina-Zubieta Grant/Research support from: GSK/HGS, N. McCormick: None Declared, E. Sayre: None Declared, M. Sadatsafavi: None Declared, J. Esdaile: None Declared, C. Marra: None Declared