Monitoring Glycemic Control

Canadian Diabetes Association Clinical Practice Guidelines Expert Committee

Lori D. Berard RN, CDE Ian Blumer MD, FRCPC Robyn Houlden MD, FRCPC David Miller MD, FRCPC Vincent Woo MD, FRCPC

  • Key Messages
  • Recommendations
  • Figures
  • Highlights
  • Full Text
  • References

Key Messages

  • Glycated hemoglobin (A1C) is a valuable indicator of treatment effectiveness and should be measured every 3 months when glycemic targets are not being met and when diabetes therapy is being adjusted.
  • Awareness of both measures of glycemia, self-monitoring of blood glucose (SMBG) results and A1C, provide the best information to assess glycemic control.
  • SMBG should not be viewed as an intervention but rather as an aid to assess interventions and hypoglycemia.
  • Timing and frequency of SMBG should be determined individually based on the type of diabetes, the treatment prescribed, the need for information about blood glucose (BG) levels and the individual's capacity to use the information from testing to modify behaviours or adjust medications.
  • SMBG and continuous glucose monitoring (CGM) should be linked with a structured educational and therapeutic program designed to facilitate behaviour change for improving BG levels.

Highlights of Revisions

  • This chapter now includes specific self-monitoring of blood glucose (SMBG) recommendations for individuals with type 2 diabetes who are not receiving insulin therapy.
  • A new appendix "Self-Monitoring of Blood Glucose (SMBG) Recommendation Tool for Healthcare Providers" has been added to aid healthcare professionals in educating and managing their patients with type 1 and type 2 diabetes (p. S352).
  • A recommendation has been added about the use of real-time continuous glucose monitoring (CGM) in patients with type 1 diabetes.

Recommendations

  • 1.For most individuals with diabetes, A1C should be measured every 3 months to ensure that glycemic goals are being met or maintained. Testing at least every 6 months should be performed in adults during periods of treatment and lifestyle stability when glycemic targets have been consistently achieved [Grade D, Consensus].
  • 2.For individuals using insulin more than once a day, SMBG should be used as an essential part of diabetes self-management [Grade A, Level 1 (1), for type 1 diabetes; Grade C, Level 3 (2), for type 2 diabetes] and should be undertaken at least 3 times per day [Grade C, Level 3 (2,3)] and include both pre- and postprandial measurements [Grade C, Level 3 (3-5)]. In those with type 2 diabetes on once-daily insulin in addition to oral antihyperglycemic agents, testing at least once a day at variable times is recommended [Grade D, Consensus].
  • 3.For individuals with type 2 diabetes not receiving insulin therapy, SMBG recommendations should be individualized depending on type of antihyperglycemic agents, level of glycemic control and risk of hypoglycemia [Grade D, Consensus].
    • When glycemic control is not being achieved, SMBG should be instituted [Grade B, Level 2 (6,7) ] and should include periodic pre- and postprandial measurements and training of healthcare providers and patients on methods to modify lifestyle and medications in response to SMBG values [Grade B, Level 2 (8)].
    • If achieving glycemic targets or receiving medications not associated with hypoglycemia, infrequent SMBG is appropriate [Grade D, Consensus].
  • 4.In many situations, for all individuals with diabetes, more frequent testing should be undertaken to provide information needed to make behavioural or treatment adjustments required to achieve desired glycemic targets and avoid risk of hypoglycemia [Grade D, Consensus].
  • 5.In people with type 1 diabetes, real-time continuous glucose monitoring may be used to improve glycemic control [Grade B, Level 2 (9)] and reduce hypoglycemia [Grade B, Level 2 (10,11)].
  • 6.In order to ensure accuracy of BG meter readings, meter results should be compared with laboratory measurement of simultaneous venous FPG at least annually and when indicators of glycemic control do not match meter readings [Grade D, Consensus].
  • 7.Individuals with type 1 diabetes should be instructed to perform ketone testing during periods of acute illness accompanied by elevated BG, when preprandial BG levels remain >14.0 mmol/L or in the presence of symptoms of DKA [Grade D, Consensus]. Blood ketone testing methods may be preferred over urine ketone testing, as they have been associated with earlier detection of ketosis and response to treatment [Grade B, Level 2 (12)].

Abbreviations:
BG, blood glucose; DKA, diabetic ketoacidosis; FPG, fasting plasma glucose; SMBG, self-monitoring of blood glucose.

References

  1. The DCCT Research Group. Epidemiology of severe hypoglycemia in the Diabetes Control and Complications Trial. Am J Med 1991;90:450e9.
  2. Karter AJ, Ackerson LM, Darbinian JA, et al. Self-monitoring of blood glucose levels and glycemic control: the Northern California Kaiser Permanente Diabetes Registry. Am J Med 2001;111:1e9.
  3. Sheppard P, Bending JJ, Huber JW. Pre- and post-prandial capillary glucose selfmonitoring achieves better glycaemic control than pre-prandial only monitoring: a study in insulin treated diabetic patients. Prac Diabetes Int 2005;22:15e22.
  4. Murata GH, Shah JH, Hoffman RM, et al, Diabetes Outcomes in Veterans Study (DOVES). Intensified blood glucose monitoring improves glycemic control in stable, insulin-treated veterans with type 2 diabetes: the Diabetes Outcomes in Veterans Study (DOVES). Diabetes Care 2003;26:1759e63.
  5. Rohlfing CL, Wiedmeyer HM, Little RR, et al. Defining the relationship between plasma glucose and HbA(1c): analysis of glucose profiles and HbA(1c) in the Diabetes Control and Complications Trial. Diabetes Care 2002;25:275e8.
  6. Davis WA, Bruce DG, Davis TM. Does self-monitoring of blood glucose improve outcome in type 2 diabetes? The Fremantle Diabetes Study. Diabetologia 2007; 50:510e5.
  7. Poolsup N, Suksomboon N, Rattanasookchit S. Meta-analysis of the benefits of self-monitoring of blood glucose on glycemic control in type 2 diabetes patients. Diabetes Technol Ther 2009;11:775e84.
  8. Polonsky WH, Fisher L, Schikman CH, et al. Structured self-monitoring of blood glucose significantly reduces A1C levels in poorly controlled, noninsulintreated type 2 diabetes: results from the Structured Testing Program study. Diabetes Care 2011;34:262e7.
  9. Deiss D, Bolinder J, Riveline JP, et al. Improved glycemic values control in poorly controlled patients with type 1 diabetes using real-time continuous glucose monitoring. Diabetes Care 2006;29:2730e2.
  10. Battelino T, Phillip M, Bratina N, et al. Effect of continuous glucose monitoring on hypoglycemia in type 1 diabetes. Diabetes Care 2011;34: 795e800.
  11. Garg S, Voelmle M, Beatson C, et al. Use of continuous glucose monitoring in subjects with type 1 diabetes on multiple daily injections versus continuous subcutaneous insulin infusion therapy. Diabetes Care 2011;34: 574e9.
  12. Bektas F, Eray O, Sari R, et al. Point of care blood ketone testing of diabetic patients in the emergency department. Endocr Res 2004;30: 395e402.

 

Reproduced with permission from Canadian Journal of Diabetes © 2013 Canadian Diabetes Association. To cite this article, please refer to For citation.