Systemic Lupus Erythematosus in a Managed Care Setting

Washington, DC—Patients with newly diagnosed and existing systemic lupus erythematosus (SLE) incur high costs and resource use compared with healthy individuals, and the costs increase in patients with SLE-related conditions such as central nervous system (CNS) disease, renal disease, and cardiovascular complications.

Recent study results were presented during a poster session at the ACR meeting. The poster was titled Medical Costs and Health Care Resource Use in Patients with Systemic Lupus Erythematosus in an Insured Population.

Previous studies have estimated the economic burden of SLE in the United States, but have not looked at newly diagnosed and existing disease separately. In the current study, the authors estimated direct medical costs and healthcare resource use of SLE by evaluating and comparing these measures in 3 cohorts of patients: (1) those with newly diagnosed SLE, (2) those with existing SLE, and (3) a comparison of each to a cohort of healthy controls. Data from a large national US managed care health plan database was used to identify patients for inclusion in the study.

All patients in the SLE cohorts were required to have a diagnosis of SLE between January 2003 through December 2008, be at least 18 years of age, have continuous enrollment with pharmacy and medical benefits for 24 months before and 12 months after the service date, have evidence of either >1 inpatient claim with a SLE diagnosis or >2 office or emergency department visits at least 30 days apart with a SLE diagnosis within 12 months of the date of service, and no claims for a SLE diagnosis in the 24 months before the date of service or claims for antimalarials, systemic corticosteroids, methotrexate, azathioprine, or mycophenolate mofetil for 12 months prior to the date of service.

Patients eligible for inclusion in the newly diagnosed SLE cohort were required to fulfill all the above criteria, whereas those eligible for the existing SLE cohort were required to fulfill all of the criteria with the exception of only being required to have 12 months of continuous enrollment prior to the service date.

Patients eligible for inclusion in the healthy controls were at least 18 years of age, had >1 office visit from 2003 to 2008, had continuous enrollment for >24 months during 2003 to 2008, and had no diagnosis of SLE, myositis, or systemic sclerosis.

The study included 1278 patients with newly diagnosed SLE who were matched by age and gender to 3834 healthy controls and 10,152 patients with existing SLE matched to 30,456 healthy controls. Multiple comorbid conditions were found in patients with SLE compared with healthy controls.

The study found that for the years between 2003 and 2008, the average annual costs of patients with newly diagnosed SLE were 3- to 4-fold higher than the average costs of matched healthy controls ($19,178 vs $4909, respectively; P<.001). Patients with existing SLE disease also had significantly higher average annual costs compared with matched healthy controls ($15,487 vs $5156; P<.001).

When adjusting for clinical and demographic characteristics, the study found that patients with newly diagnosed and existing SLE had higher overall costs than matched healthy controls and that evidence of renal disease, CNS disease, cardiovascular complications as well as use of multiple medications were predictors of higher cost.

The largest cost driver among the newly diagnosed SLE patients was inpatient cost, whereas ambulatory cost was the largest cost driver for patients with existing SLE.

According to the investigators, limitations of the study included focusing only on direct medical costs without examining indirect medical costs, lack of differentiating the severity of disease among patients, and focusing only on a managed care population that may not be generalizable to other populations.