This Article  • Full text  • PDF  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Citing articles on HighWire  • Citing articles on Web of Science (58)  • Contact me when this article is cited  Related Content  • Related articles  • Similar articles in JAMA  Topic Collections  • Endocrine Diseases  • Diabetes Mellitus  • Humanities  • Humanities, Other  • Alert me on articles by topic  Social Bookmarking   What's this?

Christopher D. Saudek, MD; Rachel L. Derr, MD; Rita R. Kalyani, MD

JAMA. 2006;295:1688-1697.

Context  With the increasing prevalence of diabetes, successful management of blood glucose control is increasingly important. Current approaches to assessing glycemia include the use of self-monitoring of blood glucose (SMBG) and hemoglobin A_1c (HbA_1c).

Objectives  To assess the evidence underlying the use of these 2 modalities, to evaluate confounders and sources of error in each test, to describe upcoming developments, and to reach evidence-based conclusions on their optimal use.

Data Sources, Study Selection, and Data Extraction  Reports identified from MEDLINE searches (1976-2005) using relevant terms were selected for quality and relevance to the stated questions. Particular attention was paid to larger cohort studies, clinical trials, meta-analyses, and established recommendations.

Data Synthesis  If used properly SMBG gives an acceptably accurate reflection of immediate plasma glucose levels. Study results vary, but in general, the evidence supports a positive effect of regular SMBG for improving glycemia, particularly in individuals treated with insulin. The best timing of SMBG and its frequency are controversial issues, but the clinical recommendation is for regular monitoring with frequency depending on the treatment and the instability of glycemia. In the relatively near term, SMBG could gradually be replaced by continuous glucose monitoring. HbA_1c measures long-term glycemic control, reflecting a time-weighted mean over the previous 3 to 4 months. There are a number of physiologic and methodologic confounders that can affect HbA_1c, but standardization of assays has been well established. The main value of HbA_1c is its use as a predictor of diabetic complications and the proven effect of improved control of HbA_1c on complication risk. A reasonable target value for HbA_1c is less than 7%. A new method for measuring HbA_1c may cause significant changes in the recommended levels, the numbers reported, and even the name of the test.

Conclusion  Assessing glycemia in diabetes can be a challenge, but approaches are available that promote successful management of blood glucose and may thereby lead to a significant reduction in morbidity and mortality related to diabetes.

Author Affiliations: Division of Endocrinology and Metabolism, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Md.

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter     What's this?

RELATED ARTICLES

Activation of Oxidative Stress by Acute Glucose Fluctuations Compared With Sustained Chronic Hyperglycemia in Patients With Type 2 Diabetes
Louis Monnier, Emilie Mas, Christine Ginet, Françoise Michel, Laetitia Villon, Jean-Paul Cristol, and Claude Colette
JAMA. 2006;295(14):1681-1687.
ABSTRACT | FULL TEXT  

Glycemic Variability: A Hemoglobin A_1c–Independent Risk Factor for Diabetic Complications
Michael Brownlee and Irl B. Hirsch
JAMA. 2006;295(14):1707-1708.
EXTRACT | FULL TEXT  

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Association of A1C and Fasting Plasma Glucose Levels With Diabetic Retinopathy Prevalence in the U.S. Population: Implications for diabetes diagnostic thresholds
Cheng et al.
Diabetes Care 2009;32:2027-2032.
ABSTRACT | FULL TEXT  

A Randomized Comparison of the Terms Estimated Average Glucose Versus Hemoglobin A1C
Brick et al.
The Diabetes Educator 2009;35:596-602.
ABSTRACT | FULL TEXT  

Racial and Ethnic Differences in Mean Plasma Glucose, Hemoglobin A1c, and 1,5-Anhydroglucitol in Over 2000 Patients with Type 2 Diabetes
Herman et al.
J. Clin. Endocrinol. Metab. 2009;94:1689-1694.
ABSTRACT | FULL TEXT  

Site-Specific GlcNAcylation of Human Erythrocyte Proteins: Potential Biomarker(s) for Diabetes
Wang et al.
Diabetes 2009;58:309-317.
ABSTRACT | FULL TEXT  

Maintaining A Physiological Blood Glucose Level with 'Glucolevel', A Combination of Four Anti-Diabetes Plants Used in the Traditional Arab Herbal Medicine
Said et al.
Evid Based Complement Alternat Med 2008;5:421-428.
ABSTRACT | FULL TEXT  

Elevated Preoperative Hemoglobin A1c Level is Associated With Reduced Long-Term Survival After Coronary Artery Bypass Surgery
Halkos et al.
Ann. Thorac. Surg. 2008;86:1431-1437.
ABSTRACT | FULL TEXT  

Systematic Review: Comparative Effectiveness and Safety of Premixed Insulin Analogues in Type 2 Diabetes
Qayyum et al.
ANN INTERN MED 2008;149:549-559.
ABSTRACT | FULL TEXT  

Elevated preoperative hemoglobin A1c level is predictive of adverse events after coronary artery bypass surgery
Halkos et al.
J. Thorac. Cardiovasc. Surg. 2008;136:631-640.
ABSTRACT | FULL TEXT  

Translating the A1C Assay Into Estimated Average Glucose Values
Nathan et al.
Diabetes Care 2008;31:1473-1478.
ABSTRACT | FULL TEXT  

A New Look at Screening and Diagnosing Diabetes Mellitus
Saudek et al.
J. Clin. Endocrinol. Metab. 2008;93:2447-2453.
ABSTRACT | FULL TEXT  

Diabetic Control and Risk of Tuberculosis: A Cohort Study
Leung et al.
Am J Epidemiol 2008;167:1486-1494.
ABSTRACT | FULL TEXT  

Letter to the Editor: Quality of Ambulatory Care for Diabetes and Lower-Extremity Amputation
Sheikh
American Journal of Medical Quality 2008;23:239-240.
 

Self-Monitoring of Blood Glucose Before and After Medicare Expansion Among Medicare Beneficiaries With Diabetes Who Do Not Use Insulin
Li et al.
AJPH 2008;98:358-364.
ABSTRACT | FULL TEXT  

Glycemic Control and Hemoglobinopathy: When A1C May Not Be Reliable
Smaldone
Diabetes Spectr. 2008;21:46-49.
FULL TEXT  

Inclusion of Biomarkers for Detecting Perturbations in the Heart and Lung and Lipid/Carbohydrate Metabolism in National Toxicology Program Studies
Dunnick et al.
Toxicol Sci 2007;100:29-35.
ABSTRACT | FULL TEXT  

Diabetes Management Issues for Patients With Chronic Kidney Disease
Cavanaugh
Clin. Diabetes 2007;25:90-97.
ABSTRACT | FULL TEXT  

Evaluation of Inaccuracies in the Measurement of Glycemia in the Laboratory, by Glucose Meters, and Through Measurement of Hemoglobin A1c
Schrot et al.
Clin. Diabetes 2007;25:43-49.
ABSTRACT | FULL TEXT  

The Foundation of Diabetes Self-management: Glucose Monitoring
Banerji
The Diabetes Educator 2007;33:87S-90S.
FULL TEXT  

Assessing Glycemic Control With Self-monitoring of Blood Glucose and Hemoglobin A1c Measurements
Dailey
Mayo Clin Proc. 2007;82:229-236.
ABSTRACT | FULL TEXT  

A 74-Year-Old Woman With Diabetes
Abrahamson
JAMA 2007;297:196-204.
ABSTRACT | FULL TEXT  

Self-monitoring of Blood Glucose: Benefits and Utilization
Austin et al.
The Diabetes Educator 2006;32:835-847.
FULL TEXT  

Glycemic Variability: A Hemoglobin A1c-Independent Risk Factor for Diabetic Complications
Brownlee and Hirsch
JAMA 2006;295:1707-1708.
FULL TEXT