Emergency department use among Michigan children with special health care needs: an introductory study.

Objective: To describe patterns of emergency department (ED) use among children dual-enrolled in Medicaid and Michigan's Children's Special Health Care Services (CSHCS).

Data Sources: Individual claims and enrollment data from Michigan's Medicaid and CSHCS programs for the period January 1, 1998, to June 30, 1999. Claims data were linked with eligibility data and then used to develop a 100 percent sample of claims for individuals enrolled in both Medicaid and CSHCS.

Study Design: Poisson regression analysis was used to examine the rate of ED use for dual-enrolled children. A time-varying hazard analysis was also used to examine the impact of changes over time. The key variables were gender, age, race, county of residence, Medicaid eligibility category, and qualifying diagnosis.

Principal Findings: Dual-enrolled children under one year of age, and those with qualifying diagnoses of anemia, hemophilia, asthma, epilepsy, and juvenile diabetes displayed especially high rates of ED use. Significant geographic variation in ED use remained after controlling for qualifying diagnoses, race/ethnicity, and other factors. African Americans displayed higher rates of ED utilization than non-Hispanic whites. Supplemental Security Income (SSI) recipients demonstrated higher utilization than other groups.

Conclusions: Children dually enrolled in CSHCS and Medicaid face diverse challenges of both poverty and chronic illness. Differences in patterns of use highlight the importance, but also the difficulty, of developing systems of care to manage complex chronic conditions in low-income populations.