title: Crowd-out and exposure effects of physical comorbidities on mental health care use: implications for racial-ethnic disparities in access.
abstract: OBJECTIVE
  In disparities models, researchers adjust for differences in "clinical need," including indicators of comorbidities. We reconsider this practice, assessing (1) if and how having a comorbidity changes the likelihood of recognition and treatment of mental illness; and (2) differences in mental health care disparities estimates with and without adjustment for comorbidities.
  
  
  METHODS
  Longitudinal data from 2000 to 2007 Medical Expenditure Panel Survey (n=11,083) split into pre and postperiods for white, Latino, and black adults with probable need for mental health care.
  
  
  METHODS
  First, we tested a crowd-out effect (comorbidities decrease initiation of mental health care after a primary care provider [PCP] visit) using logistic regression models and an exposure effect (comorbidities cause more PCP visits, increasing initiation of mental health care) using instrumental variable methods. Second, we assessed the impact of adjustment for comorbidities on disparity estimates.
  
  
  RESULTS
  We found no evidence of a crowd-out effect but strong evidence for an exposure effect. Number of postperiod visits positively predicted initiation of mental health care. Adjusting for racial/ethnic differences in comorbidities increased black-white disparities and decreased Latino-white disparities.
  
  
  CONCLUSIONS
  Positive exposure findings suggest that intensive follow-up programs shown to reduce disparities in chronic-care management may have additional indirect effects on reducing mental health care disparities.
authors.affiliation: Center for Multicultural Mental Health Research, 120 Beacon Street, Somerville, MA 02143, USA. bcook@charesearch.org
authors.forename: Benjamin Lê
authors.initials: BL
authors.lastname: Cook
authors.forename: Thomas G
authors.initials: TG
authors.lastname: McGuire
authors.forename: Margarita
authors.initials: M
authors.lastname: Alegría
authors.forename: Sharon-Lise
authors.initials: SL
authors.lastname: Normand
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D015897:Comorbidity; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data; D006302:Health Services Research / Q000706:statistics & numerical data; D054625:Healthcare Disparities / Q000208:ethnology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008605:Mental Health Services / Q000706:statistics & numerical data*; D008875:Middle Aged; D011787:Quality of Health Care / Q000706:statistics & numerical data; D044469:Racial Groups / Q000706:statistics & numerical data*; D012959:Socioeconomic Factors; D055815:Young Adult