title: VA and Medicare Utilization Among Dually Enrolled Veterans with Type 2 Diabetes: A Latent Class Analysis.
abstract: BACKGROUND
  Many Veterans treated within the VA Healthcare System (VA) are also enrolled in fee-for-service (FFS) Medicare and receive treatment outside the VA. Prior research has not accounted for the multiple ways that Veterans receive services across healthcare systems.
  
  
  OBJECTIVE
  We aimed to establish a typology of VA and Medicare utilization among dually enrolled Veterans with type 2 diabetes.
  
  
  METHODS
  This was a retrospective cohort.
  
  
  METHODS
  316,775 community-dwelling Veterans age ≥ 65 years with type 2 diabetes who were dually enrolled in the VA and FFS Medicare in 2008-2009.
  
  
  METHODS
  Using latent class analysis, we identified classes of Veterans based upon their probability of using VA and Medicare diabetes care services, including patient visits, laboratory tests, glucose test strips, and medications. We compared the amount of healthcare use between classes and identified factors associated with class membership using multinomial regression.
  
  
  RESULTS
  We identified four distinct latent classes: class 1 (53.9%) had high probabilities of VA use and low probabilities of Medicare use; classes 2 (17.2%), 3 (21.8%), and 4 (7.0%) had high probabilities of VA and Medicare use, but differed in their Medicare services used. For example, Veterans in class 3 received test strips exclusively through Medicare, while Veterans in class 4 were reliant on Medicare for medications. Living ≥ 40 miles from a VA predicted membership in classes 3 (OR 1.1, CI 1.06-1.15) and 4 (OR 1.11, CI 1.04-1.18), while Medicaid eligibility predicted membership in class 4 (OR 4.30, CI 4.10-4.51).
  
  
  CONCLUSIONS
  Veterans with diabetes can be grouped into four distinct classes of dual health system use, representing a novel way to characterize how patients use multiple services across healthcare systems. This classification has applications for identifying patients facing differential risk from care fragmentation.
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.|Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Radomski
authors.affiliation: Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.|Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, USA.
authors.forename: Carolyn T
authors.initials: CT
authors.lastname: Thorpe
authors.affiliation: Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.|Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, USA.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Thorpe
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.|Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.|Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, PA, USA.|Pharmacy Benefits Management Services, U.S. Department of Veterans Affairs, Hines, IL, USA.
authors.forename: Chester B
authors.initials: CB
authors.lastname: Good
authors.affiliation: Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.|Department of Biostatistics, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: Maria K
authors.initials: MK
authors.lastname: Mor
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.|Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Fine
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA. walid.gellad@va.gov.|Center for Health Equity Research and Promotion, VA Pittsburgh Healthcare System, University Drive, 151C, Pittsburgh, PA, 15240, USA. walid.gellad@va.gov.
authors.forename: Walid F
authors.initials: WF
authors.lastname: Gellad
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003627:Data Interpretation, Statistical; D003695:Delivery of Health Care / Q000706:statistics & numerical data; D003924:Diabetes Mellitus, Type 2 / Q000628:therapy*; D005260:Female; D006302:Health Services Research / Q000379:methods; D006787:Hospitals, Veterans / Q000706:statistics & numerical data*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D008297:Male; D006278:Medicare / Q000706:statistics & numerical data*; D011934:Reagent Strips; D012189:Retrospective Studies; D014481:United States; D014728:Veterans / Q000706:statistics & numerical data*
chemical_list: D007004:Hypoglycemic Agents; D011934:Reagent Strips
keywords: Medicare; Veterans; diabetes; health services research; utilization