Impact of health maintenance organizations and fee-for-service on health care utilization among people with systemic lupus erythematosus

OBJECTIVE: To compare health care utilization in people with systemic lupus erythematosus (SLE) in health maintenance organizations (HMOs) and fee-for-service (FFS). METHODS: A structured survey was administered to a cohort of 982 people with SLE who were assembled between 2002 and early 2005. A total of 2,656 person-years of observation were completed by the end of 2005. In each year, respondents reported their health care utilization and whether they had HMO or FFS coverage. We compared health care utilization of those in HMOs and FFS, with and without adjustment for socioeconomic, demographic, and health characteristics using repeated-measures regression techniques. RESULTS: Compared with people with SLE who were in FFS, those in HMOs were younger (3.3 years), received a diagnosis at an earlier age (3.6 years), had slightly less disease activity (0.4 on a 10-point scale), were more likely to be nonwhite (8.8%), were less likely to be below the poverty line (7.8%), and were less likely to have public insurance (29.7%). The 2 groups did not differ in other characteristics. On an unadjusted basis, subjects with SLE in HMOs had significantly fewer physician visits (3.1; 95% confidence interval 95% CI] 1.7, 4.5) and were less likely to report one or more outpatient surgical visits (6.3%; 95% CI 2.5, 10.0), and hospital admissions (5.5%; 95% CI 1.7, 9.3) than those in FFS. Adjustment reduced the differences in physician visits (2.3; 95% CI 1.1, 3.5), outpatient surgical rates (4.4%; 95% CI 0.6, 8.1), and hospital admission rates (4.0%, 95% CI 0.4, 7.7). CONCLUSION: Subjects with SLE in HMOs utilized substantially less ambulatory care and were less likely to have outpatient surgery and hospital admissions than those in FFS; the effects were not completely explained by socioeconomic, demographic, and health characteristics.