Exploring patterns of health service use in older emergency department patients.

OBJECTIVES: Study objectives were to identify groups of older patients with similar patterns of health care use in the 12 months preceding an index outpatient emergency department (ED) visit and to identify patient-level predictors of group membership.
METHODS: Subjects were adults ≥ 65 years of age treated and released from an academic medical center ED. Latent cluster analysis (LCA) models were estimated to identify groups with similar numbers of primary care (PC), specialist, and outpatient ED visits and hospital days within 12 months preceding the index ED visit.
RESULTS: In this sample (n = 308), five groups with distinct patterns of health service use emerged. Low Users (35%) had fewer visits of all types and fewer hospital days compared to sample means. Low Users were more likely to be female and had fewer chronic health conditions relative to the overall sample (p < 0.05). The ED to Supplement Primary Care Provider (PCP) (23%) group had more PCP visits, but also significantly more ED visits. Specialist Heavy (22%) group members had twice as many specialist visits, but no difference in PCP visits. Members of this class were more likely to be white and male (p < 0.05). High Users (15%) received more care in all categories and had more chronic baseline health conditions (p < 0.05) but no differences in demographic characteristics relative to the whole sample. The ED and Hospital as Substitution Care (6%) group had fewer PC and specialist visits, but more ED visits and hospital days.
CONCLUSIONS: In this sample of older ED patients, five groups with distinct patterns of health service use were identified. Further study is needed to determine whether identification of these patient groups can add important information to existing risk-assessment methods.