Introduction

Canadian Diabetes Association Clinical Practice Guidelines Expert Committee

Alice Y.Y. Cheng MD, FRCPC

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

Every 5 years, since 1992, the Clinical & Scientific Section (C&SS) of the Canadian Diabetes Association has published comprehensive, evidence-based recommendations for healthcare professionals to consider in the prevention and management of diabetes in Canada. They have served as a helpful resource and aid for anyone caring for people with diabetes and are recognized, not only in Canada but also internationally, as high-quality, evidence-based clinical practice guidelines (1) . In fact, an analysis by Bennett et al (1) demonstrated that the Canadian Diabetes Association clinical practice guidelines are among the best in the world with respect to quality, rigour and process (1) . For these 2013 Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada, volunteer members of the Clinical Practice Guidelines Expert Committee assessed the peer reviewed evidence published since 2008 relevant to the prevention and management of diabetes. They then incorporated the evidence into revised diagnostic, prognostic and therapeutic recommendations for the care of Canadians living with diabetes, as well as recommendations for measures to delay the onset of diabetes for populations at high risk of developing type 2 diabetes.

A number of important changes have occurred in the development of the 2013 clinical practice guidelines:

  • Expansion of the Expert Committee to include 120 healthcare professional volunteers from across Canada; Expert Committee members bring expertise from diverse practice settings and include professionals from family medicine, endocrinology, internal medicine, infectious disease, neurology, nephrology, cardiology, urology, psychology, obstetrics, ophthalmology, pediatrics, nursing, dietetics, pharmacy, exercise physiology and others.
  • Inclusion and active participation of people with diabetes on the Expert Committee to ensure that their views and preferences informed the guideline development process and the recommendations.
  • Update and expansion of previous chapters and, in some cases, amalgamation of previous chapters into others to increase utility and relevance.
  • Inclusion of a drug cost appendix for pharmacological therapies as a reference for clinicians.
  • Update and expansion of our Methodology process (e.g. updated literature searches throughout the guideline development process, expansion of the Duality of Interest policy) (see Methods chapter, p. S4).
  • Inclusion of a “Practical Tips” box, where appropriate, to facilitate implementation of the recommendations.
  • Expanded harmonization of recommendations through collaboration with other organizations, including the Canadian Hypertension Education Program (CHEP), the Society of Obstetricians and Gynecologists of Canada (SOGC), the Canadian Cardiovascular Society (CCS) and the Canadian Cardiovascular Harmonization of National Guidelines Endeavour (C-CHANGE).
  • Expanded dissemination and implementation strategy with increased use of technology.

It is hoped that primary care physicians and other healthcare professionals who care for people with diabetes or those at risk of diabetes will continue to find the evidence compiled in these guidelines a vital aid and resource in their efforts. We are confident that, ultimately, if applied properly, these guidelines will lead to improved quality of care, reduced morbidity and mortality from diabetes and its complications, and a better quality of life for people living with this chronic disease.

The Challenge of Diabetes

Diabetes mellitus is a serious condition with potentially devastating complications that affects all age groups worldwide. In 1985, an estimated 30 million people around the world were diagnosed with diabetes; in 2000, that figure rose to over 150 million; and, in 2012, the International Diabetes Federation (IDF) estimated that 371 million people had diabetes (2) . That number is projected to rise to 552 million (or 1 in 10 adults) by 2030, which equates to 3 new cases per second (2) . Although the largest increase is expected to be in countries with developing economies, Canada also will be impacted significantly. As of 2009, the estimated prevalence of diabetes in Canada was 6.8% of the population—2.4 million Canadians (3) —a 230% increase compared to prevalence estimates in 1998. By 2019, that number is expected to grow to 3.7 million (3) . Diabetes is the leading cause of blindness, end stage renal disease (ESRD) and nontraumatic amputation in Canadian adults. Cardiovascular disease is the leading cause of death in individuals with diabetes and occurs 2- to 4-fold more often than in people without diabetes. People with diabetes are over 3 times more likely to be hospitalized with cardiovascular disease, 12 times more likely to be hospitalized with ESRD and over 20 times more likely to be hospitalized for a nontraumatic lower limb amputation compared to the general population (3) . Diabetes and its complications increase costs and service pressures on Canada's publicly funded healthcare system. Among adults aged 20 to 49 years, those with diabetes were 2 times more likely to see a family physician and 2 to 3 times more likely to see a specialist (3) . Also, people with diabetes were 3 times more likely to require hospital admission in the preceding year with longer lengths of stay (3) . Therefore, the impact of diabetes is significant not only for individuals but also for their families and for society as a whole.

Delaying the Onset of Type 2 Diabetes

Prevention of type 1 diabetes has not yet been successful, but remains an active area of research. However, there is good evidence that delaying the onset of type 2 diabetes results in significant health benefits, including lower rates of cardiovascular disease and renal failure (4) . In 2007, the IDF released a “Consensus on Type 2 Diabetes Prevention” and called upon the governments of all countries to develop and implement a National Diabetes Prevention Plan (4) . The IDF proposed that strategies be implemented for 2 separate groups: those at high risk of developing type 2 diabetes, and the entire population at large. Among those at high risk, the proposed 3-step approach was to A) identify those who may be at higher risk, B) measure the risk, and C) intervene to delay/prevent the onset of type 2 diabetes using predominantly health behaviour strategies to affect the modifiable risk factors for type 2 diabetes. As of 2013, Canada does not have such a strategy in place. There remains an urgent and increasing need for governments to invest in research to define effective strategies and programs to prevent and treat obesity and to encourage physical activity. In addition, Canada's diverse population, with some ethnic groups disproportionally affected by diabetes, requires that health promotion, and disease prevention and management strategies be culturally appropriate and tailored to specific populations. They also should include policies aimed at addressing poverty and other systemic barriers to healthcare (5).

Optimal Care of Diabetes

Effective diabetes care should be delivered within the framework of the Chronic Care Model and centred around the individual who is practicing, and supported in, self-management (see Organization of Care chapter, p. S20). To achieve this, an interprofessional team with the appropriate expertise is required, and the system needs to support and allow for sharing and collaboration between primary care and specialist care as needed. A multifactorial approach utilizing an interprofessional team addressing healthy behaviours, glycemic control, blood pressure control, lipid management and vascular protection measures has been shown to effectively and dramatically lower the risk of development and progression of serious complications for individuals with diabetes (6–9) . In addition, individuals with diabetes must be supported in the skills of self-management since their involvement in disease management is absolutely necessary for success. People with diabetes require training in goal setting, problem solving and health monitoring, all of which are critical components of self-management. They also need access to a broad range of tools, including medications, devices and supplies to help them achieve the recommended blood glucose, cholesterol and blood pressure targets. Health outcomes depend on managing the disease effectively, and, without access to the necessary tools and strategies, Canadians living with diabetes will not be able to achieve optimal results. All levels of government should commit to investing in chronic care management and support of the tools needed for successful self-management to ensure that optimal care can be delivered.

Research

Canada continues to be a world leader in diabetes research. This research is essential for continued improvement in the lives of people with diabetes. Regulatory agencies should not apply these guidelines in a rigid way with regard to clinical research in diabetes. It is suggested that study protocols may include guideline recommendations, but individual decisions belong in the domain of the patient-physician relationship. The merits of each research study must be assessed individually so as to not block or restrict the pursuit of new information. The Canadian Diabetes Association welcomes the opportunity to work with regulatory agencies to enhance research in Canada and, ultimately, to improve the care of people with diabetes.

Cost Considerations

When it comes to the issue of cost, caution is required when identifying direct, indirect and induced costs for treating diabetes (10) . In fact, the 2011 Diabetes in Canada report from the Public Health Agency of Canada could not report the total economic burden of diabetes, but concluded that the costs will only increase substantially as the prevalence of the disease increases over time (3) . Nonetheless, in 2009, the Canadian Diabetes Association commissioned a report to evaluate the economic burden of diabetes using a Canadian Diabetes Cost Model, which utilizes the data from the Canadian National Diabetes Surveillance System (NDSS) and the Economic Burden of Illness in Canada (EBIC) (11) . In this report, the estimated economic burden of diabetes was $12.2 billion in 2010 and projected to increase by another $4.7 billion by 2020. It is certainly the hope and expectation of all stakeholders that the evidence-based prevention and management of diabetes in a multifactorial fashion will reduce the economic burden of the disease (3,6,12).

These clinical practice guidelines, like those published before, have purposefully not taken into account cost effectiveness in the evaluation of the evidence surrounding best practice. The numerous reasons for this have been outlined in detail previously (13) . Some of these reasons include the paucity of cost-effectiveness analyses using Canadian data, the difficulty in truly accounting for all the important costs (e.g. hypoglycemia) in any cost-effectiveness analysis, the lack of expertise and resources to properly address the cost-effectiveness analyses needed for all the clinical questions within these clinical practice guidelines and, perhaps more importantly, the philosophical question of which is more important: clinical benefit to the patient or cost to the system? At what level of cost effectiveness should one consider a therapy worth recommending? For these 2013 clinical practice guidelines, the question of whether the committee should incorporate cost considerations was discussed again, and a Cost Consideration Working Group, consisting of health economists and health outcomes researchers, was convened. The mandate of the group was to develop a proposal to the Clinical Practice Guidelines Steering Committee describing how cost issues might be incorporated into the guidelines, considering feasibility and impact. Based on issues of feasibility and philosophical considerations of our role as recommendation developers, it was decided that cost would not be included in the recommendations to ensure that they reflect the best available clinical evidence for the patient. The issue of evidence-based vs. cost-effective healthcare is an ethical debate that should involve all citizens because the outcome of this debate ultimately impacts every Canadian. However, it is recognized and acknowledged that both the healthcare professional and the patient should consider cost when deciding on therapies. Therefore, drug costs are included in Appendix 5, allowing for easy reference for both clinicians and patients alike.

Other Considerations

In Canada, the glycated hemoglobin (A1C) continues to be reported using National Glycohemoglobin Standardization Program (NGSP) units (%). In 2007, a consensus statement from the American Diabetes Association, the European Association for the Study of Diabetes and the IDF called for A1C reporting worldwide to change to dual reporting of A1C with the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) SI units (mmol/mol) and derived NGSP units (%) with the hope of fully converting to exclusive reporting in SI units (14) . However, this has not been adopted worldwide, with both Canada and the United States still using the NGSP units (%) (15) . Although there are some advantages to reporting in SI units, the most notable disadvantage is the massive education effort that would be required to ensure recognition and adoption of the new units. At this time, Canada is not performing dual reporting. Therefore, throughout this document, the A1C will still be written in NGSP units (%). For those who wish to convert NGSP units to SI units, the following equation can be used: (16) IFCC = 10.93(NGSP) – 23.50.

Dissemination and Implementation

Despite the strength of the evidence supporting the multifactorial treatment of people with diabetes to reduce complications, a recent national cross-sectional survey conducted around World Diabetes Day (November 14, 2012) demonstrated that only 13% of 5123 patients with type 2 diabetes had achieved all 3 metabolic targets (glycemia, lipids and blood pressure) (17) . Therefore, a care gap remains and the effective dissemination and implementation of these 2013 clinical practice guidelines is critical. A Dissemination & Implementation Chair was appointed at the beginning of the guidelines process. Strategies were developed to increase practitioner implementation and to improve patient care and health outcomes. A Dissemination & Implementation Committee was created to develop a strategic plan to be implemented at the launch of the guidelines and to continue for years thereafter. These volunteers from across Canada are involved in creating a 3-year plan to translate the evidence compiled in the guidelines into community practice. An Executive Summary will be distributed to healthcare professionals in Canada. The full guidelines will continue to be available online, and summary articles will be strategically placed in journals and newsletters. In addition, key messages and tools supporting specific themes from the guidelines will be highlighted in technology-based and paper-based awareness campaigns over the next few years. Primary care physicians, healthcare providers, government officials, Canadians living with diabetes and the general public continue to be the audiences for these campaigns.

Clinical Practice Guidelines and Clinical Judgement

“Neither evidence nor clinical judgment alone is sufficient. Evidence without judgment can be applied by a technician. Judgment without evidence can be applied by a friend. But the integration of evidence and judgment is what the healthcare provider does in order to dispense the best clinical care.” (Hertzel Gerstein, 2012)

People with diabetes are a diverse and heterogeneous group; therefore, it must be emphasized that treatment decisions need to be individualized. Guidelines are meant to aid in decision making by providing recommendations that are informed by the best available evidence. However, therapeutic decisions are made at the level of the relationship between the healthcare professional and the patient. That relationship, along with the importance of clinical judgement, can never be replaced by guideline recommendations. Evidence-based guidelines try to weigh the benefit and harm of various treatments; however, patient preferences are not always included in clinical research, and, therefore, patient values and preferences must be incorporated into clinical decision making (18) . For some of the clinical decisions that we need to make with our patients, strong evidence is available to inform those decisions, and these are reflected in the recommendations within these guidelines. However, there are many other clinical situations where strong evidence may not be available, or may never become available, for reasons of feasibility. In those situations, the consensus of expert opinions, informed by whatever evidence is available, is provided to help guide and aid the clinical decisions that need to be made at the level of the patient. It is also important to note that clinical practice guidelines are not intended to be a legal resource in malpractice cases as outlined in the Canadian Medical Association Handbook on Clinical Practice Guidelines (19).

Conclusions

Diabetes is a complex and complicated disease. The burgeoning evidence on new technologies and therapeutic treatments is rapidly expanding our knowledge and ability to manage diabetes and its complications; at the same time, however, it is challenging for physicians and other healthcare professionals who care for people with diabetes. These 2013 clinical practice guidelines contain evidence-based recommendations that provide a useful reference tool to help healthcare professionals translate the best available evidence into practice. The hope is that these guidelines will provide government officials with the evidence they need when rationalizing access to healthcare so that the potentially beneficial health outcomes are maximized for people living with diabetes. Healthcare professionals are encouraged to judge independently the value of the diagnostic, prognostic and therapeutic recommendations published in the 2013 Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada.

References

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  2. International Diabetes Federation. IDF Diabetes Atlas 5th ed. 2012 International Diabetes Federation Brussels www.idf.org/diabetesatlas Accessed February 21, 2013
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Reproduced with permission from Canadian Journal of Diabetes © 2013 Canadian Diabetes Association. To cite this article, please refer to For citation.