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HbA1c Screening A Must In All Hospitals

Jul 2, 2016

Diabetes screening should be protocol test in all health centers, health fairs to prevent undiagnosed diabetes and avoid later complications.

Diabetes screening tests include fasting plasma glucose (FPG) and oral glucose tolerance tests (OGTTs), which are normally used among high-risk individuals.  Recently the American Diabetes Association (ADA) has proposed glycated hemoglobin (HbA1c) testing as the favored test to diagnose diabetes. Since the early stages of diabetes don’t show any physical signs and can remain undetected for a longer time, diabetes testing should be added for every patient who visits any health care facility. Complications of diabetes such as coronary vascular disease, cerebrovascular disease and peripheral vascular disease as well as retinopathy, neuropathy and nephropathy may develop. Routine diabetes testing will help prevent all these complications and in the end can save the patient some money — or even their life.


The purpose or objective of this study was to evaluate the prevalence of undiagnosed diabetes in hospitalized patients and the need for using HbA1c testing. For this observational study, adults with the exception of pregnant women were studied for 3 months upon admission at a hospital. Of the 4,691 patients admitted, 3,873 of them had their blood samples drawn due to usual clinical care; of this, 2,672 had a random plasma glucose (RPG) level ≥99mg/dL.(5.5mmol/L.). A branch of the recruited patients agreed to participate in oral glucose tolerance test (OGTTs) and were prompted within 3 months of discharge to go do the test. Patients were grouped as either known diabetic, undiagnosed diabetic or no diabetes with undiagnosed diabetic having an HbA1c of ≥ 6.5%. ANOVA, Scheffe, Mann-Whitney U and the X2 test were the main statistical analysis done.

The diabetic group was 21.5% with a CI of 95%, with an RPG ≥ 99mg/dL.(5.5mmol/L.) Of the 11.1% undiagnosed diabetes patients, the CI was 9.8%-12.4%. For the HbA1c level,s 35% of the 11% with unknown diabetes had values between 5.7%- 6.4%, which is considered to be an increased risk for diabetes. Of the 43 patients who completed OGTT, their CI was 95%.

Of the admitted patients, 11% had RPG ≥ 99mg/dL.(5.5mmol/L) in over 3 months. HbA1c should be enforced as a protocol in all hospital settings since it is cheap and a good way of detecting undiagnosed diabetes. Further studies, however, need to be performed to know how these results could be integrated in communities with adequate resources for follow up. HbA1c testing had some limitations, which included hospitalized patients having increased cell turnover and blood transfusion. Also, admitted patients will only benefit from diabetes diagnosis if there is enough resources to manage the disease in their communities.

In another study, “Prevalence of Elevated Hemoglobin A1c among Patients Admitted to the Hospital without a Diagnosis of Diabetes,” 695 adult patients admitted to an acute care hospital revealed a prevalence of unrecognized probable diabetes of 18% based on HbA1c levels higher than 6.1%, with 5% of the sample having HbA1c over 6.5%. These patients did not have significant hyperglycemia during the hospital admission. Patients with undiagnosed probable diabetes are at risk for development and progression of complications of diabetes before clinical recognition of their metabolic abnormalities, yet only 15% of these patients were recognized as having diabetes within 1 yr of follow-up. Screening with HbA1c levels at the time of admission to an acute care hospital may represent an opportunity to identify a high-risk group of patients with unrecognized diabetes or prediabetes and, if coupled with effective follow-up, to promote prevention of subsequent diabetes-related complications.

Patients without diabetes had a mean HbA1c of 5.57 ± 0.39%. Patients with unrecognized probable diabetes had mean HbA1c of 6.48 ± 0.41%. Patients with type 1 diabetes (n = 9) had mean HbA1c of 7.78 ± 1.21%, and patients with type 2 diabetes (n = 127) had HbA1c of 7.39 ± 1.68%. Length of stay was not significantly different among patients without diabetes, with unrecognized probable diabetes, and with diabetes.

Practice Pearls:

  • Diabetes screening should be added to all health center protocol visits.
  • Early stages of diabetes are asymptomatic and can go undetected for many years; therefore constant screening should be done to avoid complications later on.
  • On average, 15% of admitted patients had an elevated A1c for diabetes or prediabetes.
  • HbA1c testing is an easy and affordable way of testing undiagnosed diabetes. It should therefore be recommended in all health centers.

Barr E, Magliano D, Zimmet P, et al. AusDiab 2005. The Australian Diabetes, Obesity and Lifestyle Study. Tracking the accelerating epidemic: its causes and outcomes. Report. Melbourne: International Diabetes Institute, 2006

American Diabetes Association. “Standards of Medical Care in Diabetes—2009.” Diabetes Care 32.Suppl 1 (2009): S13–S61. PMC. Web. 6 June 2016.

Tapp, Robyn J. et al. “Longitudinal Association of Glucose Metabolism With Retinopathy: Results from the Australian Diabetes Obesity and Lifestyle (AusDiab) Study.” Diabetes Care 31.7 (2008): 1349–1354. PMC. Web. 6 June 2016.

Wexler, Deborah J. et al. “Prevalence of Elevated Hemoglobin A1c among Patients Admitted to the Hospital without a Diagnosis of Diabetes.” The Journal of Clinical Endocrinology and Metabolism 93.11 (2008): 4238–4244. PMC. Web. 6 June 2016.

J Clin Endocrinol Metab. 2008 Nov; 93(11): 4238–4244.