Journal of General Internal Medicine

, Volume 27, Issue 10, pp 1368–1376 | Cite as

Insurance Status, not Race, is Associated with Mortality After an Acute Cardiovascular Event in Maryland

  • Derek K. NgEmail author
  • Daniel J. Brotman
  • Bryan Lau
  • J. Hunter Young
Original Research



It is unclear how lack of health insurance or otherwise being underinsured contributes to observed racial disparities in health outcomes related to cardiovascular disease.


To determine the relative risk of death associated with insurance and race after hospital admission for an acute cardiovascular event.


Prospective cohort study in three hospitals in Maryland representing different demographics between 1993 and 2007.


Patients with an incident admission who were either white or black, and had either private insurance, state-based insurance or were uninsured. 4,908 patients were diagnosed with acute myocardial infarction, 6,759 with coronary atherosclerosis, and 1,293 with stroke.


Demographic and clinical patient-level data were collected from an administrative billing database and neighborhood household income was collected from the 2000 US Census. The outcome of all-cause mortality was collected from the Social Security Death Master File.


In an analysis adjusted for race, disease severity, location, neighborhood household income among other confounders, being underinsured was associated with an increased risk of death after myocardial infarction (relative hazard, 1.31 [95 % CI: 1.09, 1.59]), coronary atherosclerosis (relative hazard, 1.50 [95 % CI: 1.26, 1.80]) or stroke (relative hazard, 1.25 [95 % CI: 0.91, 1.72]). Black race was not associated with an increased risk of death after myocardial infarction (relative hazard, 1.03 [95 % CI: 0.85, 1.24]), or after stroke (relative hazard, 1.18 [95 % CI: 0.86, 1.61]) and was associated with a decreased risk of death after coronary atherosclerosis (relative hazard, 0.82 [95 % CI: 0.69, 0.98]).


Race was not associated with an increased risk of death, before or after adjustment. Being underinsured was strongly associated with death among those admitted with myocardial infarction, or a coronary atherosclerosis event. Our results support growing evidence implicating insurance status and socioeconomic factors as important drivers of health disparities, and potentially racial disparities.


health disparities insurance coverage socioeconomic status race cardiovascular disease 



The authors thank Chris Cobbs and the Johns Hopkins Casemix department for use of the data and anonymous reviewers in an earlier manuscript draft.

Conflict of Interest

The authors declare that they do not have a conflict of interest.

Supplementary material

11606_2012_2147_MOESM1_ESM.pdf (114 kb)
ESM 1 (PDF 113 kb)


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Copyright information

© Society of General Internal Medicine 2012

Authors and Affiliations

  • Derek K. Ng
    • 1
    Email author
  • Daniel J. Brotman
    • 2
  • Bryan Lau
    • 1
    • 2
  • J. Hunter Young
    • 1
    • 2
  1. 1.Department of EpidemiologyJohns Hopkins Bloomberg School of Public HealthBaltimoreUSA
  2. 2.Department of MedicineJohns Hopkins Medical InstitutionsBaltimoreUSA

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