SAT0649-HPR DIRECT COSTS OF SYSTEMIC LUPUS ERYTHEMATOSUS IN COLOMBIA
Authors: J. S. Castro Villarreal, A. Beltrán-Ostos, C. F. Valencia Arboleda
Journal: Annals of the Rheumatic Diseases (2020)

Background: Treatment burden of Systemic Lupus Erythematosus (SLE) is considered high. There are no studies in Colombia that includes the estimation of an incremental cost associated to SLE. Objectives: To estimate the direct cost associated to SLE in contributory healthcare scheme in Colombia. To estimate prevalence and characterize SLE population affiliated in the contributory healthcare scheme in Colombia. To estimate the direct healthcare cost in patients with and without SLE and the effect of being diagnosed with SLE in the total direct cost during a period of two years. Methods: The present study was carried out with an administrative database that includes all the enrollees in the contributive health scheme for a period of 4 years. It was established an operative definition to identify individuals with the disease in order to make the descriptive analysis and calculation of prevalence. every patient was aged 18 or older on index date. Additionally, as the length of follow-up period was fixed to two years, all patients whose index 14 date had been greater than 1st January 2016 were excluded from the study sample (Figure 1). The variables considered in this part of the study were demografiphc), clinical (Charlson Comorbidity Index) and cost-related variables, which was the outcome variable of the study, this cost was made up of the sum of all medical costs, regardless of whether they were related or not to SLE. Costs were adjusted for inflation, to values in 2017. To evaluate the effect of having SLE vs. not having, on the direct cost in health, propensity scores analysis was used to reduce differences in the baseline characteristics. Three groups were formed based on disease severity: high (patients who had renal failure), medium (patients in intensive care unit at least once but without renal failure) and low (remaining SLE patients) (See table 1). Results: From 2014 to 2017, 21,993 SLE patients were identified. Women represented 87.4% of the cases, 5428 patients were selected to make up the sample of SLE patients. the number of patients without diagnosis of SLE was 19,419,540. From this population was drawn randomly a 10% size sample, to make up the potential control sample. To estimate the incremental cost of having SLE it was used multivariate regression through a GAM model. The estimated average annual total cost of a patient with SLE was $6,139,046 COP vs. non-SLE patient cost of $4,113,191 COP. Meanwhile the adjusted incremental cost of SLE vs non-SLE was $2,025,855 COP. Subsequently, adjusted incremental cost was estimated taking into account the levels of severity. In the Table 1 are presented the mean values of incremental costs and 95% confidence intervals. Table 1. Incremental cost by degree of severity Degree of Severity Average adjust incremental cost per year (in COP ) Confidence interval construction method Confidence interval (95 %) (in COP ) High $ 19,930,931.67 t-interval $16,525,728.01, $ 23,336,135.32 Bootstrap $17,088,627.49, $ 23,068,518.89 Medium $7,248,201.04 t-interval $2,123,742.99, $12,372,659.09 Bootstrap $3,460,932.89, $11,688,205.25 Low $ 885,300.40 t-interval $642,925.6, $ 1,127,675.2 Bootstrap $ 688,197.5, $ 1,098,098.2 Conclusion: Although the prevalence of SLE in Colombia is relatively low, the direct costs generated for this disease might be very high. The annual cost for a SLE patient was $2,025,855 COP greater than the cost of a non-SLE patient. When considering the severity levels of the disease, it was found a $ 19,930,931.67 incremental cost estimate for high level of severity. In the medium level, the estimate was $ 7,248,201.04. Meanwhile, a patient in the low severity level had a $ 885,300.40 incremental cost. References: [1]Kan HJ, Song X, Johnson BH, Bechtel B, O’Sullivan D, Molta CT. Healthcare utilization and costs of systemic lupus erythematosus in Medicaid. Biomed Res Int. 2013;2013:808391. doi: 10.1155/2013/808391. Disclosure of Interests: None declared