Journal of General Internal Medicine

, Volume 33, Issue 2, pp 142–144 | Cite as

Doc, I Just Ate: Interpreting Random Blood Glucose Values in Patients with Unknown Glycemic Status

  • Michael E. Bowen
  • Lei Xuan
  • Ildiko Lingvay
  • Ethan A. Halm
Concise Research Letters


Clinicians frequently order random blood glucose (RBG) in routine laboratory panels. Although RBG values ≥200 mg/dL with hyperglycemic symptoms are diagnostic of diabetes, interpreting RBG results below this threshold is challenging, because the impact of food and calorie-containing drinks on glucose in non-fasting individuals is unclear. As a result, clinicians often ignore RBG values1—even though they are strongly associated with undiagnosed diabetes and prediabetes and can identify those at risk of dysglycemia.2,3 To improve interpretation of RBG values in non-fasting individuals without self-reported dysglycemia, we stratified participants in the National Health and Nutrition Examination Survey (NHANES) by hemoglobin A1C (HbA1c) and characterized the relationship between RBG and time since last caloric intake.


We analyzed merged data from the 2007–2012 NHANES—a stratified survey representative of the non-institutionalized US population. Non-pregnant adults...


random glucose prediabetes diabetes screening dysglycemia 



M.B. participated in the design, analysis, data interpretation, and drafting of the manuscript. L.X. participated in analysis, data interpretation, and manuscript revision. I.L. participated in the data interpretation and manuscript revision. E.H participated in the design, analysis, data interpretation, and manuscript revision.

M.B. had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.


This study was conducted using resources provided by the UT Southwestern Center for Patient-Centered Outcomes Research (AHRQ R24 HS022418).

Dr. Bowen was supported by the NIH/NIDDK (K23 DK104065), the National Center for Advancing Translational Sciences of the NIH (KL2TR001103), and the Dedman Family Endowed Program for Scholars in Clinical Care. Drs. Halm and Xuan were supported in part by AHRQ R24 HS022418.

The content of this manuscript is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or the Agency for Healthcare Research and Quality. The funding sources had no involvement in study design; data collection, analysis, or interpretation; writing the report; or submission for publication.

Compliance with Ethical Standards

Prior Presentations

Preliminary data from this study were presented at the 2015 Society of General Internal Medicine National Meeting, Toronto, Ontario, Canada.

Conflict of Interest

The authors report no potential conflicts of interest relevant to this work.


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Copyright information

© Society of General Internal Medicine 2017

Authors and Affiliations

  • Michael E. Bowen
    • 1
    • 2
  • Lei Xuan
    • 2
  • Ildiko Lingvay
    • 3
    • 4
  • Ethan A. Halm
    • 1
    • 2
  1. 1.Division of General Internal Medicine, Department of Medicine University of Texas Southwestern Medical CenterDallasUSA
  2. 2.Division of Outcomes and Health Services Research, Department of Clinical SciencesUniversity of Texas Southwestern Medical CenterDallasUSA
  3. 3.Division of Endocrinology, Department of MedicineUniversity of Texas Southwestern Medical CenterDallasUSA
  4. 4.Department of Clinical SciencesUniversity of Texas Southwestern Medical CenterDallasUSA

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