Category: CDE

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CDE Diabetes

Study Guide: Targets for Glycemic Control (Chapter 8)

1. Chapter Overview

This chapter answers the critical question: “How low should we go?” It balances the benefits of intensive glycemic control (reduced microvascular and long-term cardiovascular complications) against the risks (hypoglycemia and mortality, particularly in high-risk groups).

For the CDE exam, you must master the individualization of targets. The “one size fits all” approach is outdated. You need to know exactly who qualifies for a target of ≤6.5% and who requires a more relaxed target of 7.1%–8.5%.

2. Key Messages (The "Gold Nuggets")

  • Fundamental Goal: Optimal glycemic control is fundamental to the management of diabetes.

  • The “Legacy Effect”: Early intensive control has long-lasting benefits. Even if control worsens later, the initial period of tight control reduces long-term complications (microvascular and CV).

  • Individualization is Mandatory: Glycemic targets should be individualized based on the individual’s frailty, functional dependence, and life expectancy.

  • A1C Composition: Both fasting plasma glucose (FPG) and postprandial plasma glucose (PPG) contribute to the A1C value.

    • Clinical Pearl: As A1C gets closer to target (≤7.0%), PPG (post-meal glucose) becomes the dominant contributor. When A1C is high, FPG (fasting) is the main driver.

3. The Evidence: Major Clinical Trials

You may be asked which trial demonstrated specific outcomes.

  • DCCT (Type 1) & UKPDS (Type 2):

    • Established that intensive control significantly reduces microvascular complications.

    • Long-term follow-up revealed the “Metabolic Memory” or “Legacy Effect,” showing significant reductions in CV outcomes and mortality years after the trials ended.

  • ACCORD (Type 2):

    • Targeted A1C <6.0% in older patients with long-standing diabetes and CV risk.

    • Result: Prematurely terminated due to higher mortality in the intensive arm.

    • Lesson: Tight control may not be safe for high-risk, older individuals with established CVD.

  • ADVANCE (Type 2):

    • Targeted A1C ≤6.5%.

    • Result: Significant reduction in nephropathy (21% reduction). No benefit on mortality/CV events during the trial.

  • VADT (Type 2):

    • Targeted A1C reduction of 1.5% in veterans with poor control.

    • Result: No initial CV benefit, but long-term observational follow-up showed a significantly lower risk of major CV events.

4. Recommended Targets (The "Numbers")

A. A1C Targets

Target A1CPatient PopulationGoal/Benefit
≤ 6.5%Adults with Type 2 diabetes at low risk of hypoglycemia.To reduce the risk of CKD (Chronic Kidney Disease) and Retinopathy.
≤ 7.0%MOST adults with Type 1 or Type 2 diabetes.To reduce the risk of microvascular and (if achieved early) CV complications.
7.1% – 8.0%Functionally dependent adults.To avoid hypoglycemia and symptomatic hyperglycemia.
7.1% – 8.5%

1. Recurrent severe hypoglycemia or hypoglycemia unawareness.

 

2. Limited life expectancy.

 

3. Frail elderly and/or with dementia.

To minimize risk of hypoglycemia and symptomatic hyperglycemia.
No TargetEnd of Life.Avoid A1C measurement. Focus on avoiding symptomatic hyperglycemia and any hypoglycemia.

B. Glucose Targets 

To achieve an A1C ≤7.0%, patients should aim for:

  • Fasting/Preprandial PG: 4.0 to 7.0 mmol/L.

  • 2-Hour Postprandial PG: 5.0 to 10.0 mmol/L.

Intensified Targets: If A1C target is not met, consider tighter targets if safe:

  • Fasting/Preprandial: 4.0 to 5.5 mmol/L.

  • 2-Hour Postprandial: 5.0 to 8.0 mmol/L.

5. Diabetes Canada Clinical Practice Guidelines Recommendations

hese are the “Must Memorize” graded recommendations for the exam.

  1. General Target: In most people with type 1 or type 2 diabetes, an A1C ≤7.0% should be targeted to reduce the risk of microvascular complications and, if implemented early, CV complications.

    • Grade A, Level 1A (Microvascular); Grade B, Level 3 (CV).

  2. Tighter Target (T2D): In people with type 2 diabetes, an A1C ≤6.5% may be targeted to reduce the risk of CKD and retinopathy, if at low risk of hypoglycemia.

    • Grade A, Level 1A.

  3. Relaxed Targets: A higher A1C target may be considered to avoid hypoglycemia and over-treatment in specific groups:

    • Functionally dependent: 7.1%–8.0%.

    • Recurrent severe hypoglycemia/unawareness: 7.1%–8.5%.

    • Limited life expectancy: 7.1%–8.5%.

    • Frail elderly/dementia: 7.1%–8.5%.

    • Grade D, Consensus for all above.

  4. End of Life: A1C measurement is not recommended. Avoid symptomatic hyperglycemia and any hypoglycemia.

    • Grade D, Consensus.

Reference:

Imran SA, Agarwal G, Bajaj HS, Ross S. Targets for Glycemic Control. Canadian Journal of Diabetes. 2018;42:S42-S46. doi:10.1016/j.jcjd.2017.10.030
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CDE Diabetes

Flash Cards: Self-Management Education and Support (Chapter 7)

Welcome to the Flash Card section for Chapter 7: Self-Management Education and Support.

While many educators feel comfortable with the “art” of teaching, the CDE exam focuses heavily on the “science” behind it. This chapter contains specific definitions and statistical evidence that are easy to confuse but essential to know.

Why use flash cards for this chapter? You might intuitively know that “support helps,” but the exam asks for specifics: How much does it help? Which type of support is best? These flash cards are designed to help you memorize the hard data points—such as specific A1C reduction percentages—and the precise definitions that differentiate “Education” from “Support.”

Key concepts covered in this deck:

  • SME vs. SMS: Drilling the definitions to ensure you can distinguish between the process of learning and the support required for maintenance.

  • Delivery Formats: Recalling the evidence grades for group vs. individual education and when to use peer support.

  • Intervention Types: Defining terms like “Cognitive Behavioural Interventions” and “Diabetes Coaching.”

Use these cards to lock in the statistics and definitions, ensuring you can answer evidence-based questions with confidence.

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CDE Diabetes

Practice Exam: Self-Management Education and Support (Chapter 7)

You have reviewed the study guide, now it is time to test your mastery of Chapter 7: Self-Management Education and Support.

For the CDE exam, it is easy to underestimate this chapter as “common sense,” but the guidelines are quite specific about the distinction between Self-Management Education (SME) and Self-Management Support (SMS). The exam will test your ability to differentiate between the initial transfer of knowledge (SME) and the ongoing scaffolding required to sustain it (SMS).

What to expect in this quiz: This practice exam focuses on the evidence-based strategies that drive patient behavior change. You will be tested on:

  • Definitions: Distinguishing between SME (a systematic intervention to gain knowledge/skills) and SMS (activities that support the maintenance of behaviors).

  • The “Numbers”: Recognizing the specific A1C reductions associated with different interventions, such as the 0.53% reduction seen with text messaging or the 0.9% reduction with telephone follow-up.

  • Delivery Formats: Knowing when group education is sufficient versus when a combination of group and individual follow-up is superior.

  • Tailoring: Identifying the correct approach for specific populations, such as using peer educators for minority groups or adding literacy-sensitive materials.

Use this quiz to ensure you can apply these educational principles to the clinical scenarios you will face on exam day.

1. A diabetes educator is designing a culturally appropriate education program. According to systematic reviews, what is the range of mean A1C reduction with culturally appropriate health education for type 2 diabetes?

2. How many hours of behavioural interventions for type 2 diabetes are associated with a reduction of A1C of at least 0.4%?

3. According to the guidelines, what reduction in first CVD episode was associated with attending structured diabetes education?

4. A diabetes educator is designing a comprehensive education program. According to the evidence, what combination of interventions is most effective in improving glycemic control?

5. According to the evidence on cognitive-behavioural interventions, what is essential for effective behaviour change?

6. Case: A patient with type 2 diabetes prefers technology-based education. According to the meta-analysis by Pal et al., what was the effect of computer-based diabetes self-management interventions on A1C?

7. According to the evidence on expanding the role of diabetes educators to include medication management, what outcomes improved?

8. What timeframe represents the typical duration after which statistically and clinically significant improvements in A1C are seldom maintained without additional SMS?

9. Case: A diabetes educator is planning family interventions. According to the systematic review, what outcomes are positively impacted when partners are involved in care?

10. A diabetes educator wants to use cognitive-behavioural interventions. Which of the following is NOT listed as a cognitive-behavioural intervention technique?

11. Which of the following is NOT listed as a basic knowledge and skill component for SME?

12. What is the primary distinction between self-management education (SME) and self-management support (SMS)?

13. A diabetes educator is planning an education program for newly diagnosed patients with type 2 diabetes. According to the evidence, which educational approach is most effective in improving glycemic control?

14. Case: A diabetes educator is considering using text messaging for patient support. According to the meta-analysis, what was the difference in A1C reported in the intervention compared to usual care?

15. According to the large population-based cohort study, attending structured diabetes education was associated with what reduction in all-cause mortality?

16. A diabetes care team wants to implement group education. According to the evidence, what is the relationship between group vs. individual settings for glycemic control?

17. A clinic is implementing Internet-delivered diabetes education. According to the evidence, what is a common challenge with Internet/web-based programs?

18. According to Diabetes Canada guidelines, what is the definition of self-management education (SME)?

19. According to the evidence on peer support interventions, which type of intervention provided the greatest A1C reduction

20. According to the evidence, what strategies help maintain engagement with Internet-delivered diabetes education?


 

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CDE Diabetes

Study Guide: Self-Management Education and Support (Chapter 7)

1. Chapter Overview

This chapter marks a shift in terminology from simply “Diabetes Education” to Self-Management Education (SME) and Self-Management Support (SMS). The addition of “Support” recognizes that education alone is often insufficient for sustaining behavior change. For the CDE exam, you must distinguish between the process of learning (SME) and the ongoing support required to maintain it (SMS).

2. Key Messages (The "Gold Nuggets")

  • The Power of Education: Structured education doesn’t just lower A1C; in people with Type 2 diabetes, it has been associated with a 44% reduction in all-cause mortality and a 20% reduction in first cardiovascular events.

  • SME vs. SMS:

    • SME (Education): A systematic intervention involving active participation to gain knowledge and skills.

    • SMS (Support): Activities that support the implementation and maintenance of these behaviours (e.g., coaching, peer support).

  • The Winning Combination: Combining SME and SMS is most advantageous for improving glycemic control, self-efficacy, and reducing diabetes distress.

  • Cognitive Behavioural Interventions: Using cognitive restructuring, problem-solving, and goal setting is more effective than didactic (lecture-style) teaching alone.

3. Self-Management Education (SME)

A. Evidence of Benefit

  • Clinical: Reductions in A1C, CV risk factors, and foot complications.

  • Economic: Lower health-care expenditures observed after 12 months.

  • Psychosocial: Improvements in quality of life, self-efficacy, and reduced diabetes distress.

B. Delivery Formats

  • Group vs. Individual: Group settings are effective for short-term control, but combining group interventions with individual follow-up results in lower A1C than either setting alone.

  • The Team Effect: Interventions using a combination of health-care professionals are superior.

    • Nurse + Team: Most effective decrease in A1C (-1.84%).

    • Nurse only: -0.80% decrease.

    • Other personnel only: -0.77% decrease.

C. Technology in SME

  • Internet/Web-based: Effective for improving glycemic control and knowledge compared to usual care.

  • Mobile Apps/Texting:

    • General mobile apps show a small beneficial effect on A1C (-0.5%).

    • Text messaging interventions specifically reported an A1C difference of 0.53% compared to usual care.

4. Tailoring Education

One size does not fit all. Tailoring is paramount.

  • Cultural Tailoring: Culturally appropriate education (language, dietary advice, faith traditions) results in A1C reductions of -0.2% to -0.5%.

  • Minority Populations: Individual, face-to-face programs with peer educators often show larger A1C reductions than group-based programs in these populations.

  • Literacy: Content geared toward low literacy/numeracy can successfully improve A1C and self-efficacy.

5. Self-Management Support (SMS)

SMS is defined as strategies that augment an individual’s ability to self-manage.

A. Key SMS Interventions & Efficacy

  1. Peer Support:

    • Overall reduction in A1C: -0.57%.

    • Individual peer support is superior to group peer support (Individual reduction: -0.91%).

  2. Community Health Workers:

    • In minority populations, access results in A1C decrease of -0.37% to -0.75%.

  3. Diabetes Coaching:

    • Involves goal setting and frequent follow-up.

    • Associated with A1C reduction of -0.32%.

  4. Telephone Follow-up:

    • A study of 4 phone calls in one year by a nurse educator resulted in an A1C 0.9% lower than those who did not receive calls.

6. Diabetes Canada Clinical Practice Guidelines Recommendations

These are the “Must Memorize” graded recommendations for the exam.

  1. Timely Education: People with diabetes should be offered timely SME that is tailored to enhance self-care.

    • Grade A, Level 1A.

  2. Cognitive-Behavioural: SME should incorporate interventions like problem-solving, goal setting, and self-monitoring.

    • Grade B, Level 2.

  3. Format: SME interventions may be offered in small group and/or one-on-one settings.

    • Grade A, Level 1A for Type 2 Diabetes.

  4. Support Strategies: Support should be offered to assist in maintaining self-management (Grade B, Level 2), specifically via:

    • Peer-led support or community support workers (Grade B, Level 2).

    • Diabetes coaching (Grade B, Level 2).

    • Telephone follow-up (Grade B, Level 2).

  5. Technology: Internet-based programs, text messages, and mobile apps may be used to improve glycemic control.

    • Grade A, Level 1A for Type 2 Diabetes.

  6. Cultural Competence: Culturally appropriate SME/SMS should be used to improve glycemic control.

    • Grade A, Level 1A.

Reference:

Sherifali D, Berard LD, Gucciardi E, MacDonald B, MacNeill G. Self-Management Education and Support. Canadian Journal of Diabetes. 2018;42:S36-S41. doi:10.1016/j.jcjd.2017.10.006
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CDE Diabetes

Flash Cards: Organization of Diabetes Care (Chapter 6)

Welcome to the Flash Card section for Chapter 6: Organization of Diabetes Care.

While clinical chapters often rely on pathophysiology and pharmacology, Chapter 6 introduces a specific organizational “language”—the Chronic Care Model (CCM). Success in this section of the CDE exam requires more than just understanding the general concepts; you need precise recall of definitions and frameworks.

Why use flash cards for this chapter? The guidelines categorize interventions into six distinct components of the CCM. On the exam, you may be asked to classify a specific activity (like a patient registry or a reminder system) into its correct component. These flash cards are designed to help you strictly define these categories and memorize the evidence-based recommendations.

Use these cards to move from passive reading to active recall, ensuring you can quickly identify the correct organizational strategy on exam day.

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CDE Diabetes

Practice Exam: Organization of Diabetes Care (Chapter 6)

Now that you have reviewed the study guide for Chapter 6: Organization of Diabetes Care, it’s time to test your knowledge.

While clinical topics like medications and screening criteria often get the most attention, the CDE exam frequently includes questions on how care is delivered. The guidelines emphasize that the structure of your practice—specifically the Chronic Care Model (CCM)—is just as vital to patient outcomes as the prescriptions you write.

What to expect in this quiz: This practice exam focuses on the “non-clinical” but essential frameworks of diabetes management. You will be tested on:

  • Identifying the 6 components of the Chronic Care Model in real-world scenarios.

  • Understanding the specific definitions of Case Management and Facilitated Relay of Information.

  • Recognizing the evidence-based benefits of Telehealth and team-based care.

  • The hierarchy of Quality Improvement (QI) strategies (e.g., knowing that multicomponent interventions are superior to single ones).

Please go to Practice Exam: Organization of Diabetes Care (Chapter 6) to view this quiz

REFERENCE

Clement M, Filteau P, Harvey B, Jin S, Laubscher T, Mukerji G, Sherifali D. Diabetes Canada Clinical Practice Guidelines Expert Committee. Organization of Diabetes Care. Can J Diabetes. 2018;42(Suppl 1):S27-S35. doi:10.1016/j.jcjd.2017.10.005

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CDE Diabetes

Study Guide: Organization of Diabetes Care (Chapter 6)

Welcome to the next section of our CDE Exam Study Guide series. While the previous chapters focused on who to screen and what prevention interventions to use, Chapter 6 shifts the focus to how that care is delivered.

“Organization of Diabetes Care” might sound dry compared to clinical topics, but do not skip this section. The CDE exam tests your understanding of the Chronic Care Model (CCM) because evidence shows that the structure of care is just as important as the medication prescribed.

Why this chapter matters for the CDE Exam:

The guidelines explicitly state that a “proactive, interprofessional team” is superior to standard care. You need to know the specific definitions of strategies like Case Management and Facilitated Relay of Information, as the exam may present a clinical scenario and ask you to identify which Quality Improvement (QI) strategy is being used.

High-Yield Exam Themes:

  1. The Shift to Proactive Care: Moving from acute, reactive care to planned, population-based care.
  2. The 6 Components of the CCM: You should be able to identify examples of Delivery System Design vs. Decision Support vs. Clinical Information Systems.
  3. Telehealth: Know that it is a proven tool for reducing A1C and improving access, particularly when it allows for medication adjustment.

Below is your study guide to mastering the organizational frameworks that underpin effective diabetes management in Canada.

1. Chapter Overview

This chapter addresses the “Care Gap”—the difference between evidence-based goals and actual clinical practice. It argues that to close this gap, we must redesign primary care using the Expanded Chronic Care Model (CCM). The goal is to transform care from “acute and reactive” to “proactive, planned, and population-based”.

 

2. Key Messages (The "Gold Nuggets")

  • Patient-Centred: Care must be organized around the person living with diabetes, who is the most important member of the team.

  • Proactive Team: Care should be facilitated by an interprofessional team that provides ongoing self-management education and support.

  • The Framework: Care should be delivered using the components of the Chronic Care Model (CCM).

  • Data-Driven: Structured care must be supported by clinical information systems (registries, reminders, audits).

3. The Chronic Care Model (CCM)

The CCM is the evidence-based framework for this chapter. It includes 6 essential components that work together. For the exam, memorize the examples for each component found in Table 1 in the guidelines.

A. Delivery System Design (How we structure the visit/team)

  • Team-Based Care: Multidisciplinary team with specific diabetes training.

  • Case Management: A structured intervention (often by a nurse, pharmacist, or dietitian) involving medication adjustment, monitoring, and care coordination. Note: Case management with medication adjustment has the greatest impact on lowering A1C.

  • Shared Care: Joint participation of primary care and specialists.

B. Self-Management Support (Empowering the patient)

  • Activities that support the patient in managing their disease (education, coaching, peer support).

  • This is the cornerstone of diabetes care in the CCM.

C. Decision Support (Helping the provider make the right choice)

  • Evidence-Based Guidelines: Embedding guidelines into EMRs.

  • Audit and Feedback: Summarizing provider performance to increase awareness.

  • Benchmarking: Comparing performance against a peer group.

D. Clinical Information Systems (The data backbone)

  • Patient Registries: A list of all patients with diabetes to track care (preventing patients from “falling through the cracks”).

  • Clinician/Patient Reminders: Prompts to recall patients or perform tasks (e.g., foot exam reminders).

  • Facilitated Relay of Information: Collection of patient data (e.g., home glucose logs) sent to the clinician, ideally one who can adjust meds.

E. The Community

  • Building healthy public policy and supportive environments.

F. Health Systems

  • Leadership and organization of healthcare.

4. Quality Improvement (QI) Strategies

  • Multi-component is Best: Interventions targeting the system (e.g., team changes + registries + case management) produce the greatest effect.

  • Effectiveness: The more CCM components used, the better the outcomes.

  • Rural Areas: Using 3 or more QI strategies significantly increases the impact on self-management compared to using a single strategy.

5. Telehealth

Telehealth is defined as the provision of healthcare remotely (telephone, video, web-based).

  • Evidence: It is one of the few QI strategies with consistent evidence for improving glycemia and cardiovascular risk factors.

  • A1C Impact: Improvement is most likely when the system allows for medication adjustment.

  • Target: A1C improvement is greater when the baseline A1C is higher (>8.0%).

6. Clinical Decision Algorithm

While this chapter is less “algorithmic” than others, visualize the workflow of an Optimized Practice:

  1. Register: Create a patient registry to identify everyone with diabetes.

  2. Recall: Use the registry to generate reminders for overdue labs/visits.

  3. Resource: Assign an interprofessional team (Nurse, Dietitian, Pharmacist) to the patient.

  4. Relay: Establish a system for the patient to send data (glucose data from CGM on CBG) to the team.

  5. Review: Use decision support tools (guidelines, flow sheets) during the visit.

7. Diabetes Canada Clinical Practice Guidelines Recommendations

Key Recommendations to Memorize:

  1. Team Care: Care should be facilitated by a proactive, interprofessional team with specific training in diabetes. 

  2. QI Strategies: The following strategies should be used to reduce A1C and improve adherence:

    • Promotion of self-management.

    • Team changes.

    • Case management.

    • Electronic patient registries.

    • Facilitated relay of clinical information.

  3. Case Manager Role: The role of the diabetes case manager should be enhanced to include interventions led by a nurse, pharmacist, or dietitian to improve coordination and facilitate timely changes to management.

  4. Telehealth: Telehealth technologies may be used to:

    • Improve self-management in underserviced communities.

    • Improve clinical outcomes (A1C, guideline adherence) in Type 2 diabetes.

Reference:

Clement M, Filteau P, Harvey B, et al. Organization of Diabetes Care. Canadian Journal of Diabetes. 2018;42:S27-S35. doi:10.1016/j.jcjd.2017.10.005
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CDE Diabetes

Flash Cards: Reducing the Risk of Developing Diabetes (Chapter 5)

Master the key concepts of diabetes prevention with these rapid-review flashcards.

With the rising prevalence of diabetes, implementing safe and cost-effective interventions is urgent to decrease the burden on individuals and the healthcare system. These flashcards are designed to help pharmacists and healthcare professionals quickly recall the evidence-based recommendations for preventing or delaying the onset of type 2 diabetes and understanding the current landscape for type 1 diabetes prevention.

 
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CDE Diabetes

Practice Exam: Reducing the Risk of Developing Diabetes (Chapter 5)

Welcome to the practice exam for Chapter 5 of the Diabetes Canada Clinical Practice Guidelines.

Welcome to the practice exam for Chapter 5 of the Diabetes Canada Clinical Practice Guidelines.

With the increasing incidence and prevalence of diabetes, the development of safe and cost-effective interventions to reduce risk is urgently needed to decrease the burden on individuals and the healthcare system. Ideally, prevention strategies should range from efforts focused on high-risk individuals to broader population-based strategies.

This practice exam focuses on the evidence-based recommendations for preventing or delaying the onset of type 2 diabetes, as well as the current status of interventions for type 1 diabetes.

Key Concepts Covered in This Exam:

  • Type 1 Diabetes Prevention: Understanding the distinction that current attempts to prevent type 1 diabetes should be undertaken only within formal research protocols.

  • Healthy Behaviour Interventions: The critical role of intensive, structured lifestyle modifications—specifically targeting a sustained weight loss of approximately 5% and regular physical activity—in reducing the risk of progression from prediabetes to type 2 diabetes by nearly 60%.

  • Dietary Patterns: Identifying evidence-based dietary patterns that reduce risk, including the Mediterranean diet, DASH diet, and the Alternate Healthy Eating Index (AHEI).

  • Pharmacotherapy: Indications for the use of pharmacologic therapy, specifically metformin, in individuals with prediabetes to delay or prevent type 2 diabetes.

  • Risk Stratification: Differentiating interventions based on risk profiles, such as Impaired Fasting Glucose (IFG), Impaired Glucose Tolerance (IGT), and elevated A1C.

Please go to Practice Exam: Reducing the Risk of Developing Diabetes (Chapter 5) to view this quiz
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CDE Diabetes

Study Guide: Reducing the Risk of Developing Diabetes (Chapter 5)

Reducing the Risk of Developing Diabetes

Welcome to the next installment of our CDE Exam Study Guide series. Now that we have covered how to identify individuals at risk in Chapter 4: Screening, we move to the crucial next step: Prevention.

Chapter 5, “Reducing the Risk of Developing Diabetes,” is a high-yield topic for the Canadian Certified Diabetes Educator (CDE) exam. As educators, we are often the first point of contact for patients diagnosed with prediabetes. Understanding the hierarchy of interventions—and specifically where pharmacotherapy fits in—is essential for both clinical practice and exam success.

Why this chapter matters for the CDE Exam:

The guidelines are very specific about the efficacy of lifestyle versus medication. A key “gold nugget” to remember is that intensive healthy behaviour interventions are the gold standard, capable of reducing the risk of type 2 diabetes by nearly 60%. In comparison, metformin reduces this risk by approximately 30%.

For the exam, focus your attention on these three areas:
  1. The “5% Rule”: The target for weight loss in prediabetes is approximately 5% of initial body weight.
  2. The Candidates for Metformin: While lifestyle is for everyone, metformin is specifically considered for those with IGT, IFG, or an A1C of 6.0%–6.4%, particularly if they are younger (<60 years), have a BMI >35 kg/m², or have a history of gestational diabetes.
  3. Type 1 vs. Type 2: Remember that while we have actionable strategies for Type 2, prevention of Type 1 diabetes is currently restricted to formal research protocols only.

Below is a summarized study guide to help you navigate the evidence, the dietary patterns (Mediterranean, DASH, AHEI), and the clinical decision flow.

 

1. Chapter Overview

This chapter focuses on interventions to prevent or delay the onset of type 2 diabetes in high-risk individuals and the current status of prevention strategies for type 1 diabetes. For the CDE exam, focus heavily on the hierarchy of interventions (Lifestyle > Metformin) and the specific dietary patterns recommended.

2. Key Messages (The "Gold Nuggets")

  • Type 1 Diabetes: As safe and effective preventive therapies have not yet been identified, prevention attempts should be undertaken only within the confines of formal research protocols.
  • Lifestyle Efficacy: Intensive healthy behaviour interventions, ideally resulting in a loss of ~5% of initial body weight, can reduce the risk of type 2 diabetes by almost 60%.
  • Durability: When initiated early, the effects of healthy behaviour interventions are long-lasting (more than 20 years).
  • Pharmacotherapy: Metformin reduces the risk of progression to type 2 diabetes by approximately 30%, with persistent benefits observed after stopping treatment.
  • Role of Dietitians: A registered dietitian can educate patients about dietary changes to reduce diabetes risk.

3. Prevention of Type 1 Diabetes

  • Current Status: Interventions such as nicotinamide (ENDIT trial), insulin injections (DPT-1), and elimination of cow’s milk protein (TRIGR) have not shown success in preventing Type 1 diabetes in general populations.
  • Clinical Rule: Attempts to prevent type 1 diabetes should be restricted to formal research protocols.

4. Prevention of Type 2 Diabetes: Interventions

A. Healthy Behaviour Interventions (First Line)

  • Target: Weight loss of approximately 5% of initial body weight.
  • Physical Activity: Moderate-intensity activity of at least 150 minutes per week.
  • Evidence:
    • DPP & DPS Trials: Showed a 58% risk reduction at 4 years.
    • Da Qing Study: 23-year follow-up showed reduced all-cause and cardiovascular mortality.

B. Dietary Patterns

There is strong evidence to support specific dietary patterns.

  • Mediterranean Diet:
    • High adherence reduces the risk of future diabetes by 19% to 23%.
    • Supplementation with Extra Virgin Olive Oil (EVOO) or mixed nuts reduced diabetes risk by 40% and 18% respectively in the PREDIMED trial.
  • DASH Diet: (Dietary Approaches to Stop Hypertension) is consistently associated with a reduced risk of type 2 diabetes.
  • AHEI: (Alternate Healthy Eating Index) is consistently associated with a reduced risk of type 2 diabetes.
  • Specific Foods:
    • Whole Grains: Consuming more than 2 servings per day is associated with a 43% reduced risk.
    • Dairy: An inverse association (more dairy = less diabetes) exists for total dairy up to 300–400 g/day.
    • Sugar-Sweetened Beverages: Higher intake is associated with higher risk, independent of body weight.

C. Pharmacotherapy

  • Metformin:
    • Efficacy: Decreased progression to diabetes by 31% compared to placebo.
    • Best Candidates: Metformin may be considered for people with Impaired Glucose Tolerance (IGT), especially if they also have Impaired Fasting Glucose (IFG) or an A1C of 6.0%–6.4%. It is most effective in younger individuals (<60 years), those with significant obesity (BMI >35 kg/m²), and women with a history of Gestational Diabetes (GDM).
  • Other Agents (Not First Line/Specific Contexts):
    • Thiazolidinediones (TZDs): Rosiglitazone and Pioglitazone reduce risk significantly (60-72%) but are not recommended for widespread use due to adverse effects like weight gain and edema.
    • Acarbose: Reduced risk by 25%, but the effect did not persist after discontinuation.
    • Liraglutide: Shown to prevent conversion to diabetes and induce weight loss, but cost and long-term safety remain considerations.
    • Orlistat: Reduced incidence by 37% but had a high dropout rate due to side effects.
    • Vitamin D: Has no significant effects on insulin resistance or prevention in trials to date.

D. Bariatric Surgery

  • Shows a drastic risk reduction (Odds Ratio 0.10).
  • Limitations: The cost-benefit analysis for primary prevention is unclear, so it is not routinely recommended solely for prevention.

5. Clinical Decision Algorithm

For the exam, visualize the flow of treatment for a patient with Prediabetes:

  1. START: Diagnose Prediabetes.
  2. INTERVENTION:
    • Healthy Behaviour Interventions (Goal: ≥5% weight loss).
    • AND/OR Dietary Patterns (Mediterranean, DASH, AHEI).
    • Consider Metformin in addition to lifestyle (esp. if high risk).
  3. MONITOR: Check A1C/FPG in 3 to 6 months.
  4. DECISION:
    • Stable/Improved? -> Maintain current strategy, follow up every 6 months.
    • Not Improved? -> Intensify healthy behaviour, consider adding/increasing Metformin.

6. 2018 Clinical Practice Guidelines Recommendations

These are the “Must Memorize” graded recommendations for the exam.

  1. Healthy Behaviour: In individuals with prediabetes, a structured program of healthy behaviour interventions that includes moderate weight loss and regular physical activity of a minimum of 150 minutes per week should be implemented to reduce the risk of type 2 diabetes.
  2. Dietary Patterns: In individuals at risk for type 2 diabetes, dietary patterns may be used to reduce the risk of diabetes, specifically:
    • Mediterranean-style.
    • DASH (Dietary Approaches to Stop Hypertension).
    • AHEI (Alternate Healthy Eating Index).
  3. Metformin: In individuals with prediabetes, pharmacologic therapy with metformin may be used to reduce the risk of type 2 diabetes.

Reference:

Prebtani APH, Bajaj HS, Goldenberg R, Mullan Y. Reducing the Risk of Developing Diabetes. Canadian Journal of Diabetes. 2018;42:S20-S26. doi:10.1016/j.jcjd.2017.10.033