Mental illness, traumatic brain injury, and medicaid expenditures

Arch Phys Med Rehabil. 2005 May;86(5):905-11. doi: 10.1016/j.apmr.2004.09.026.


Objective: To estimate the rates of mental illness among Medicaid beneficiaries with traumatic brain injury (TBI) and associated Medicaid-paid expenditures.

Design: Retrospective claims-based calendar year data.

Setting: Claims data.

Participants: Medicaid recipients with diagnosed TBI and mental illness who received Medicaid services in 4 states in 1995.

Interventions: Not applicable.

Main outcome measures: Annual expenditures for total, inpatient, and noninpatient services, as derived from Medicaid personal summary files. Mental illness and TBI were identified by using International Classification of Diseases, 9th Revision , Clinical Modification codes recorded in Medicaid claims.

Results: Of a total of 493,663 Medicaid recipients, 3641 (0.7%) were diagnosed with TBI in the 4 states. Significant demographic and racial differences were found in the rates of TBI; 18% of patients with TBI were diagnosed with serious mental illness. People with TBI in the age group 40 to 49 years were more likely to have a mental disorder. There were significant differences in estimated total, inpatient, and noninpatient expenditures between those with and without mental illness. In general, those with serious mental illness had higher Medicaid-paid expenditures than those without any mental illness.

Conclusions: Psychiatric comorbidity in TBI increases the overall expenditures in this population. This increased cost is an important consideration in programming for those with TBI.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Brain Injuries / economics*
  • Comorbidity
  • Female
  • Health Expenditures / statistics & numerical data*
  • Humans
  • Male
  • Medicaid / economics*
  • Mental Disorders / economics*
  • Middle Aged
  • Proportional Hazards Models
  • United States