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Research ArticlePractice

Update on the Canadian Diabetes Association 2008 clinical practice guidelines

Onil K. Bhattacharyya, Elizabeth A. Estey and Alice Y.Y. Cheng
Canadian Family Physician January 2009, 55 (1) 39-43;
Onil K. Bhattacharyya
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Elizabeth A. Estey
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Alice Y.Y. Cheng
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This article has a correction. Please see:

  • Corrections - March 01, 2009

Rates of diabetes are increasing in Canada,1 and family physicians remain the main point of primary care for people with diabetes.2 The challenge for physicians in this context is to design realistic treatment plans and negotiate priorities to maximize health benefits for these patients. This article summarizes recommendations from the Canadian Diabetes Association (CDA) 2008 clinical practice guidelines (CPGs). The guidelines are available on-line at www.diabetes.ca/for-professionals/resources/2008-cpg/. This review covers the care of adults with type 2 diabetes and gives particular attention to new recommendations. To assist with readability, grading and evidence levels have been simplified to single letters (eg, grade A recommendation = [A]). Table 1 summarizes the grading system used by the CDA.

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Table 1

Criteria for assigning levels of evidence and grades to recommendations for clinical practice

Glycemic control and diabetes

Targets for glycemic control

The new guidelines recommend a target hemoglobin A1c (HbA1c) level of ≤ 7% for all patients with diabetes (A). A more aggressive target of ≤ 6.5% can be considered for some patients to help prevent microvascular complications, but this benefit must be weighed against an increase in mortality in patients at very high risk of cardiovascular (CV) events (A).

The benefit of achieving the target HbA1c level of ≤7% for microvascular risk reduction is well established.3 The 2003 CPGs also suggested a more aggressive target of ≤6%, but 2 recent randomized controlled trials showed no macrovascular benefit to this target. The ACCORD trial demonstrated that a therapeutic strategy to lower the level of HbA1c to <6% in high-risk patients did not reduce the risk of macrovascular disease and, in fact, was associated with a small increase in mortality.4 The ADVANCE trial did not show this increased mortality, but it also did not demonstrate macrovascular benefit of lowering the HbA1c level below 6.5%; it did, however, show a reduction in nephropathy in the intensive-control group.5 In contrast, the posttrial monitoring of the United Kingdom Prospective Diabetes Study (UKPDS-PTM) demonstrated a reduction in myocardial infarction and all-cause mortality in the subgroup with intensive glycemic control after a 10-year posttrial follow-up.6 The key differences between the UKPDS-PTM and the ACCORD and ADVANCE trials are UKPDS-PTM’s early intervention and longer follow-up. This suggests that earlier intervention has lasting benefit but that a target HbA1c level of ≤7% is more appropriate in patients at high risk of vascular events who have had diabetes for a long time.

Monitoring glycemic control

Patients with type 2 diabetes taking once-daily insulin and oral antihyperglycemic agents should monitor their blood glucose at least once a day at different times (D), or more often if they are on multiple doses of insulin (C). Because there is contradictory evidence about the benefit of self-monitoring of blood glucose for patients who are not taking insulin, self-monitoring should be individualized according to the type of treatment and level of control (D).

Pharmacologic management of type 2 diabetes

As more antihyperglycemic agents become available, careful consideration should be given to their advantages and disadvantages. Figure 1 summarizes the key points from the guidelines. Metformin remains the initial drug for type 2 diabetes, but the guidelines now support its use in all people with diabetes, irrespective of body weight (D). When glycemic targets are not met with metformin alone, 1 or more agents from a different class should be added to metformin. The choice of second-line agents depends on the desired (and undesired) characteristics of the treatment. The incretin agent, dipeptidyl peptidase-4 inhibitor, is a new option. In the presence of marked hyperglycemia (HbA1c ≥ 9%), the 2008 CPGs recommend starting combination pharmacologic therapy immediately, concurrent with lifestyle changes (D). When basal insulin is added to antihyperglycemic agents, the guidelines recommend considering insulin analogues (eg, insulin detemir or insulin glargine) instead of neutral protamine Hagedorn (NPH) to reduce risk of nocturnal or symptomatic hypoglycemia (A).

Figure 1
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Figure 1

Pharmacologic management of type 2 diabetes

Cardiovascular risk and diabetes

Cardiovascular disease (CVD) is the number 1 cause of death among those with diabetes.7 Thus, a thorough assessment of CV risk and implementation of a treatment plan (if necessary) is essential for all patients with diabetes (D).

Cardiovascular risk assessment

The degree of benefit of medical intervention is based on patients’ absolute risk of CV events, with higher-risk patients deriving greater benefit.8 Thus, identifying those at high risk can ensure that those who are most likely to benefit will receive treatment. Age is among the strongest predictors of risk, so the CDA recommends that men 45 years and older and women 50 years and older should be considered high risk. Patients below these age cutoffs, but meeting any 1 of the other important CV risk factors, should also be considered high risk.

Vascular protection

People with diabetes develop vascular disease approximately 15 years earlier than people without diabetes.9 The concept of vascular protection was introduced in the 2003 CPGs, but it has been further stratified in the 2008 version, owing to evidence that shows a comprehensive multifactorial approach to vascular protection substantially reduces complications.10,11 All patients with diabetes should receive interventions to reach target blood pressure (BP) of < 130/80 mm Hg and HbA1c levels of ≤ 7%, to stop smoking, and to maintain healthy diets, physical activity, and healthy body weight. On top of these interventions, those found to be at high risk should be prescribed angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs),12 lipid-lowering medications (particularly statins), and possibly acetylsalicylic acid (ASA). It is important to note that ARBs are now included in the CPGs as an alternative to ACE inhibitors. Specific reference to statins is also new and reflects the growing literature on the benefits of these medications for high-risk groups.13,14 Recommendations regarding ASA have also been modified, because ASA therapy has been shown to have less of a cardioprotective effect in patients with diabetes than in those without diabetes, and to have no benefit in primary prevention.15,16 Thus, the 2008 CPGs state that low-dose ASA therapy (81 to 325 mg) could be considered in people with stable CVD (D) but clinical judgement should be exercised regarding its use in primary prevention (D).

Treatment of hypertension

Strict control of BP improves morbidity and mortality in patients with diabetes.3,17–19 The CDA recommends that BP be measured at every visit and hypertension be diagnosed according to the national hypertension guidelines (www.hypertension.ca/chep). Treatment targets remain systolic BP < 130 mm Hg (C) and diastolic BP < 80 mm Hg (B). Clinical trials have shown that multiple medications and titrations are required to achieve these targets.18,20 A summary of recommended first-line and combination medications is provided in Table 2, but it is important to note that ACE inhibitors and ARBs are given special consideration as first-line treatment agents because of their renal benefits (D)12 and that α-blockers are not recommended as first-line agents for patients with diabetes (A).

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Table 2

Hypertension medication for patients with diabetes

Treatment of dyslipidemia

Dyslipidemia is a well-recognized risk factor for CVD. Fasting lipid levels should be measured at the time of diagnosis and every 1 to 3 years afterward (D). The primary target of therapy is the low-density lipoprotein cholesterol level (LDL-C) (≤ 2.0 mmol/L in patients at high risk [A]); the secondary target is the ratio of total cholesterol (TC) to high-density lipoprotein cholesterol (HDL-C) (< 4 mmol/L in patients at high risk [D]). Statins are the first-line treatment for dyslipidemia in patients with diabetes. If targets cannot be achieved with statins alone, combination therapy with ezetimibe, fibrate, or niacin can be considered (B), although there are no completed trials demonstrating clinical outcomes. Hypertriglyceridemia (triglyceride levels > 10.0 mmol/L) should be treated with fibrates to reduce the risk of pancreatitis (D).

Screening for coronary artery disease

Asymptomatic cardiac ischemia is common among those with diabetes. Many patients who present with myocardial infarction have no preceding symptoms. To identify those with established coronary artery disease in the absence of symptoms, the 2008 CPGs recommend that baseline electrocardiograms be conducted in all individuals older than 40 years of age (D).

Lifestyle modification and diabetes

Lifestyle modifications are important for treatment and prevention of diabetes. Many of the 2008 recommendations on nutrition and exercise are the same as or similar to those in the 2003 guidelines. One new recommendation is that patients be referred to and supported by exercise specialists. Structured physical activity counseling by health care providers increases physical activity and produces modest, sustained weight loss21–24; the effects of simply recommending that patients exercise more, which most clinicians do, are less certain.25

Conclusion

Clinical practice guidelines are designed to enable health care providers to engage with the evidence and better apply it in their practices. For conditions like type 2 diabetes, which are complex and multidimensional, treatment plans should be developed and discussed with patients. This might require stepwise introduction of various treatments and tests, and continued patient education, so that patients understand the value that each intervention has for optimizing their health.

Recommended targets for glycemic control

  1. Patients should be treated to achieve a target HbA1c level of ≤ 7% to reduce microvascular complications in all (A) and macrovascular complications in type 1 diabetes (C).

  2. To reach an HbA1c level of ≤ 7%, people with diabetes should aim for the following:

    • fasting plasma glucose or preprandial plasma glucose target of 4.0–7.0 mmol/L (B) and

    • 2-hr postprandial plasma glucose target of 5.0–10.0 mmol/L (B).

  3. Further postprandial blood glucose lowering to 5.0–8.0 mmol/L might be considered if HbA1c targets are not reached with the postprandial target of 5.0–10.0 mmol/L (D).

Cardiovascular risk assessment recommendations

  1. All patients with diabetes should be assessed for cardiovascular risk annually (D).

  2. Patients with diabetes are considered high risk if they are

    • male ≥ 45 y or female ≥ 50 y (B) or

    • male < 45 y or female < 50 y with any of the following (D):

      • - macrovascular or microvascular disease,

      • - 2 or more cardiac risk factors (eg, first-degree relative with premature coronary or cerebrovascular disease, smoking, hypertension, dyslipidemia),

      • - an extreme single risk factor (eg, systolic blood pressure > 180 mm Hg or low-density lipoprotein level > 5.0 mmol/L), or

      • - diabetes for longer than 15 y and age > 30 y.

Recommendations for vascular protection

  1. For vascular protection for all individuals with diabetes ([A] for patients older than 40 y with type 2 diabetes and microalbuminuria; [D] for all others), aim for the following:

    • HbA1c level ≤ 7.0% (see glycemic control),

    • blood pressure < 130/80 mm Hg,

    • smoking cessation,

    • physical activity,

    • healthy diet, and

    • healthy body weight.

  2. For high-risk patients, prescribe 1 or more of the following:

    • angiotensin-converting enzyme inhibitor or angiotensin receptor blocker ([A] for those with vascular disease; [B] for other high-risk groups),

    • a lipid-lowering medication, particularly statins (see Treatment of dyslipidemia), or

    • acetylsalicylic acid (for secondary prevention).

Recommendations for treatment of dyslipidemia

  1. Fasting lipid levels TC, HDL-C, TG, and LDL-C should be measured at the time of diagnosis and then every 1–3 y.

  2. The primary target of therapy for adults is LDL-C (A); the secondary target is the TC/HDL-C ratio (D).

  3. Adults at high risk of vascular events should be treated with statins to achieve LDL-C levels ≤ 2.0 mmol/L (A).

  4. TC/HDL-C ratio < 4.0 mmol/L should be targeted through glycemic control and lifestyle modification (D).

  5. If TG levels are > 10 mmol/L, treat with a fibrate to prevent pancreatitis (D).

Recommendations for treatment of hypertension

  1. Blood pressure (BP) should be measured at every diabetes clinic visit and hypertension should be diagnosed according to the national hypertension guidelines (D).

  2. Treatment should target BP < 130/80 mm Hg ([C] for systolic BP; [B] for diastolic BP).

  3. Most people require multiple BP-lowering medications to reach BP targets. Pharmacologic recommendations are summarized in Table 2.

  4. Lifestyle interventions to reduce BP (eg, healthy weight, low sodium intake) should be encouraged alongside pharmaceutical interventions (D).

Footnotes

  • Competing interests

    Dr Bhattacharyya is on the executive committee of the clinical and scientific section of the Canadian Diabetes Association (CDA) and on the Guideline Dissemination and Implementation Committee of the CDA. Dr Cheng served on the expert and steering committees for the CDA 2008 guidelines.

  • Copyright© the College of Family Physicians of Canada

References

  1. ↵
    Public Health Agency of CanadaNational diabetes fact sheet. Canada 2007Ottawa, ONPublic Health Agency of Canada2007Available from: www.phac-aspc.gc.ca/ccdpc-cpcmc/diabetes-diabete/english/pdf/diabetes07_e.pdfAccessed 2008 Dec 3
  2. ↵
    JaakkimainenLShahBRKoppAHuxJEBoothGLSlaughterPMLaupacisASources of physician care for people with diabetesDiabetes in Ontario: an ICES practice atlasToronto, ONInstitute for Clinical Evaluative Sciences2003
  3. ↵
    UK Prospective Diabetes Study (UKPDS) GroupIntensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33)Lancet1998352913183753Erratum in: Lancet 1999;354(9178):602
    OpenUrlCrossRefPubMed
  4. ↵
    Action to Control Cardiovascular Risk in Diabetes Study GroupEffects of intensive glucose lowering in type 2 diabetesN Engl J Med200835824254559
    OpenUrlCrossRefPubMed
  5. ↵
    The ADVANCE Collaborative GroupIntensive blood glucose control and vascular outcomes in patients with type 2 diabetesN Engl J Med200835824256072
    OpenUrlCrossRefPubMed
  6. ↵
    HolmanRRPaulSKBethelMAMatthewsDRNeilHA10-year follow-up of intensive glucose control in type 2 diabetesN Engl J Med200835915157789
    OpenUrlCrossRefPubMed
  7. ↵
    BoothGLKapralMKFungKTuJVRecent trends in cardiovascular complications among men and women with and without diabetesDiabetes Care2006291327
    OpenUrlAbstract/FREE Full Text
  8. ↵
    JacksonRLawesCMBennettDAMilneRJRodgersATreatment with drugs to lower blood pressure and blood cholesterol based on an individual’s absolute cardiovascular riskLancet2005365945743441
    OpenUrlCrossRefPubMed
  9. ↵
    BoothGLKapralMKFungKTuJVRelation between age and cardiovascular disease in men and women with diabetes compared with non-diabetic people: a population-based retrospective cohort studyLancet200636895292936
    OpenUrlCrossRefPubMed
  10. ↵
    GaedePLund-AndersenHParvingHHPedersenOEffect of a multifactorial intervention on mortality in type 2 diabetesN Engl J Med2008358658091
    OpenUrlCrossRefPubMed
  11. ↵
    GaedePVedelPLarsenNJensenGVParvingHHPedersenOMultifactorial intervention and cardiovascular disease in patients with type 2 diabetesN Engl J Med2003348538393
    OpenUrlCrossRefPubMed
  12. ↵
    ONTARGET InvestigatorsTelmisartan, ramipril, or both in patients at high risk for vascular eventsN Engl J Med200835815154759
    OpenUrlCrossRefPubMed
  13. ↵
    ColhounHMBetteridgeDJDurringtonPNHitmanGANeilHALivingstoneSJPrimary prevention of cardiovascular disease with atorvastatin in type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS): multicentre randomised placebo-controlled trialLancet2004364943568596
    OpenUrlCrossRefPubMed
  14. ↵
    BaigentCKeechAKearneyPMBlackwellLBuckGPollicinoCEfficacy and safety of cholesterol-lowering treatment: prospective meta-analysis of data from 90,056 participants in 14 randomised trials of statinsLancet20053669493126778
    OpenUrlCrossRefPubMed
  15. ↵
    CollaborationATCollaborative meta-analysis of randomised trials of antiplatelet therapy for prevention of death, myocardial infarction, and stroke in high risk patientsBMJ200232473297186
    OpenUrlAbstract/FREE Full Text
  16. ↵
    ETDRS InvestigatorsAspirin effects on mortality and morbidity in patients with diabetes mellitus. Early Treatment Diabetic Retinopathy Study report 14JAMA1992268101292300
    OpenUrlCrossRefPubMed
  17. ↵
    SchmittdielJVijanSFiremanBLafataJEOestreicherNSelbyJVPredicted quality-adjusted life years as a composite measure of the clinical value of diabetes risk factor controlMed Care200745431521
    OpenUrlCrossRefPubMed
  18. ↵
    UK Prospective Diabetes Study GroupTight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes: UKPDS 38BMJ19983177160703
    OpenUrlAbstract/FREE Full Text
  19. ↵
    CDC Diabetes Cost-effectiveness GroupCost-effectiveness of intensive glycemic control, intensified hypertension control, and serum cholesterol level reduction for type 2 diabetesJAMA200228719254251
    OpenUrlCrossRefPubMed
  20. ↵
    WheltonPKBarzilayJCushmanWCDavisBRIiamathiEKostisJBClinical outcomes in antihypertensive treatment of type 2 diabetes, impaired fasting glucose concentration, and normoglycemia: Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)Arch Intern Med20051651214019
    OpenUrlCrossRefPubMed
  21. ↵
    PetrellaRJKovalJJCunninghamDAPatersonDHCan primary care doctors prescribe exercise to improve fitness? The Step Test Exercise Prescription (STEP) projectAm J Prev Med200324431622
    OpenUrlCrossRefPubMed
  22. KirkAMutrieNMacIntyrePFisherMEffects of a 12-month physical activity counselling intervention on glycaemic control and on the status of cardiovascular risk factors in people with type 2 diabetesDiabetologia200447582132
    OpenUrlCrossRefPubMed
  23. WolfAMConawayMRCrowtherJQHazenKYNadlerLOneidaBTranslating lifestyle intervention to practice in obese patients with type 2 diabetes: Improving Control with Activity and Nutrition (ICAN) studyDiabetes Care200427715706
    OpenUrlAbstract/FREE Full Text
  24. ↵
    NorrisSLZhangXAvenellAGreggEBrownTJSchmidCHLong-term non-pharmacologic weight loss interventions for adults with type 2 diabetesCochrane Database Syst Rev20052CD004095
  25. ↵
    HarrisSBPetrellaRJLeadbetterWLifestyle interventions for type 2 diabetes. Relevance for clinical practiceCan Fam Physician200349161825
    OpenUrlAbstract/FREE Full Text
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Update on the Canadian Diabetes Association 2008 clinical practice guidelines
Onil K. Bhattacharyya, Elizabeth A. Estey, Alice Y.Y. Cheng
Canadian Family Physician Jan 2009, 55 (1) 39-43;

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Onil K. Bhattacharyya, Elizabeth A. Estey, Alice Y.Y. Cheng
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