Journal of General Internal Medicine

, Volume 28, Issue 2, pp 208–215 | Cite as

Differential Impact of Longitudinal Medication Non-Adherence on Mortality by Race/Ethnicity among Veterans with Diabetes

  • Leonard E. EgedeEmail author
  • Cheryl P. Lynch
  • Mulugeta Gebregziabher
  • Kelly J. Hunt
  • Carrae Echols
  • Gregory E. Gilbert
  • Patrick D. Mauldin
Original Research



To examine the differential effect of medication non-adherence over time on all-cause mortality by race/ethnicity.


Data on a longitudinal cohort of veterans with type 2 diabetes was examined. The main outcome was time to death. Primary independent variables were race/ethnicity and mean medication possession ratio (MPR) categorized into quintiles over the study period. Cox regression was used to model the association between time to death and MPR quintiles and race/ethnicity, adjusting for relevant covariates.


The cohort of 629,563 veterans was followed for 5 years. After adjusting for all covariates, the hazard ratios (HR) for subjects in the lowest versus highest MPR quintile was 12.21 (95 % CI 11.89, 12.55) for non-Hispanic white (NHW), 10.01 (95 % CI 9.18, 10.91) for non-Hispanic black (NHB), 12.65 (95 % CI 11.10, 14.43) for Hispanic and 10.41 (95 % CI 9.06, 11.96) for Other race veterans. Furthermore, type of diabetes therapy (oral versus insulin) maintained a significant relationship with mortality that varied by racial/ethnic group.


This study demonstrates the differential impact of medication non-adherence on mortality by race. It also demonstrates that type of diabetes therapy (insulin with or without oral agents) is associated with mortality and varies by racial/ethnic group.


medication non-adherence veterans diabetes mortality race/ethnicity 




This study was supported by grant #IIR-06-219 funded by the VHA Health Services Research and Development (HSR&D) program. The funding agency did not participate in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript. The manuscript represents the views of the authors and not those of the VA or HSR&D. All authors had access to the data and contributed to the manuscript

Conflict of Interest

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

Supplementary material

11606_2012_2200_MOESM1_ESM.pdf (132 kb)
ESM 1 (PDF 131 kb)


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Copyright information

© Society of General Internal Medicine 2012

Authors and Affiliations

  • Leonard E. Egede
    • 1
    • 2
    Email author
  • Cheryl P. Lynch
    • 1
    • 2
  • Mulugeta Gebregziabher
    • 1
    • 3
  • Kelly J. Hunt
    • 1
    • 3
  • Carrae Echols
    • 1
  • Gregory E. Gilbert
    • 1
  • Patrick D. Mauldin
    • 2
    • 4
    • 5
  1. 1.Center for Disease Prevention and Health Interventions for Diverse Populations, Ralph H Johnson Veterans Affairs Medical CenterCharlestonUSA
  2. 2.Center for Health Disparities ResearchMedical University of South CarolinaCharlestonUSA
  3. 3.Division of Biostatistics & EpidemiologyMedical University of South CarolinaCharlestonUSA
  4. 4.Department of MedicineMedical University of South CarolinaCharlestonUSA
  5. 5.Division of General Internal Medicine & GeriatricsCharlestonUSA

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