Highlights: Diabetes in Canada: Facts and figures from a public health perspective

Report highlights

This report presents the most recent statistics on the burden and impact of type 1 and type 2 diabetes mellitus ("diabetes") in Canada. It outlines complications attributable to the disease, ways of reducing the risks, and provides some estimates of the economic burden of diabetes. Finally, the report provides information on diabetes among children and youth, as well as among First Nations, Inuit and Métis populations.

The quality of surveillance information on diabetes in Canada has increased substantially over the last decade. The Canadian Chronic Disease Surveillance System uses population-based administrative data from every province and territory to provide detailed, comparative information for assessing the burden, as well as the use of health services and certain health outcomes of chronic diseases, including diabetes. Population surveys provide additional data on diabetes, its risk factors, complications and impacts on the lives of affected Canadians. The combination of these complementary data sources provides information to the Public Health Agency of Canada's diabetes surveillance program.

Chapter 1 – The burden of diabetes in Canada

• In 2008/09, almost 2.4 million Canadians (6.8%) were living with diabetes.
• According to data obtained from blood samples, about 20% of diabetes cases remain undiagnosed.
• While the prevalence increased with age, more than 50% of Canadians diagnosed with diabetes (1.2 million) were of working age, between 25 and 64 years of age.
• The overall prevalence was higher among males (7.2%) than females (6.4%).
• Newfoundland and Labrador, Nova Scotia, and Ontario had the highest age-standardized prevalence rates of diagnosed diabetes in Canada; Nunavut, Alberta, and Quebec had the lowest.
• From 1998/99 to 2008/09, the prevalence of diagnosed diabetes among Canadians increased by 70%. The greatest relative increase in prevalence was seen in the 35 to 39 and 40 to 44 year age groups, where the proportion doubled. Likely, this increase in younger age groups is, in part, a consequence of increasing rates of overweight and obesity.
• In 2008/09, more than 200,000 Canadians were newly diagnosed with diabetes (6.3 cases per 1,000 individuals).
• Just under half of new cases of diabetes were diagnosed in individuals aged 45 to 64 years old. Survey data indicate that in this age group, 47.5% of individuals with diabetes were obese compared to 19.1% of individuals without diabetes, implying that obesity was a major contributor to diabetes in this age group.
• The overall incidence of diabetes during an 11 year period (from 1998/99 to 2008/09) has been slightly increasing, particularly among children aged one to 19 years and among working-age adults aged 30 to 49 years. This increase was seen mainly in Ontario, British Columbia, Saskatchewan, and the Northwest Territories.
• If incidence and mortality rates continue at levels seen in 2008/09 data, estimates suggest that the number of Canadians living with diabetes will reach 3.7 million by 2018/19.

Chapter 2 – The health impact of diabetes on Canadians

• Individuals with diabetes are over three times more likely to be hospitalized with cardiovascular disease than individuals without diabetes, 12 times more likely to be hospitalized with end-stage renal disease, and almost 20 times more likely to be hospitalized with non-traumatic lower limb amputations.
• Diabetes was the primary cause of 34% of new cases of end-stage renal disease in 2009, creating a growing demand for renal replacement therapy (dialysis or transplant) in Canada.
• Because diabetes shares several risk factors with other chronic diseases, 36.5% of Canadian adults with diabetes reported having two or more other serious chronic conditions (hypertension, heart disease, chronic obstructive pulmonary disease, mood disorder, and/or arthritis) in addition to diabetes, and 12.5% reported having three or more.
• Nearly 40% of Canadian adults who reported having diabetes rated their health as "fair" or "poor", compared to a tenth of the adult population without diabetes (10.3%).
• Although only 3.1% of all deaths in Canada were attributed to diabetes in 2007, more than a quarter (29.9%) of individuals who died had diabetes in 2008/09. Diabetes itself does not typically lead directly to death, but the complications associated with diabetes do.
• At every age group, individuals with diabetes experienced mortality rates at least two times higher than those without. This results in noticeable decreases in life expectancy as well as health-adjusted life expectancy.
• Based on available data, it is calculated that more than one in ten deaths in Canadian adults could be prevented if diabetes rates were reduced to zero.

Chapter 3 – The health system and economic impact of diabetes

• In 2008/09, adults aged 20 to 49 years with diabetes saw a family physician twice as often as those without diabetes, and specialists two to three times more often.
• Individuals with diabetes were three times more likely to have been hospitalized at least once during the year than those without diabetes, and had a longer hospital stay.
• Annual per capita health care costs have been estimated to be three to four times greater in a population with diabetes compared to a population without the disease.
• The most recent cost estimates available for this report are outdated by 11 years, which is a major information gap. Therefore, it is difficult to assess the real economic burden of diabetes. However, it is expected that costs will only continue to rise with the increasing prevalence of diabetes and its associated health care costs.

Chapter 4 – Reducing the risk of type 2 diabetes and its complications

• Social, economic, environmental, genetic and lifestyle factors have a significant effect on the distribution of type 2 diabetes and its risk factors in the Canadian population.
• The causes of type 2 diabetes are complex and its development cannot be explained by any single risk factor. Advancing age, obesity, physical inactivity, certain ethnicities, and a family history of diabetes (or gestational diabetes in women) are all important risk factors.
• Adults who are obese are two to four times more likely to have type 2 diabetes. In 2007-2009, 23.9% of adults aged 18 years and older were obese according to measured weight and height.
• Physical activity is important for both diabetes prevention and management. In 2009-2010, almost half (47.4%) of Canadians aged 12 years and older reported that they were physically inactive (leisure and transportation index).
• In 2009-2010, more than half of Canadians aged 12 years and older (55.9%) reported eating less than five servings of vegetables and fruit a day. Inadequate consumption of vegetables and fruit is used as a proxy measure of unhealthy diet, which is a risk factor for type 2 diabetes, largely through its effects on body weight.
• Smoking has also been associated with an increased risk of type 2 diabetes and its complications. Rates of tobacco smoking have been declining in Canada over the last several years, from 17.9% in 2003 to 15.5% in 2010.
• Socio-demographic factors, including lower socio-economic status, belonging to certain ethnic groups, and living in rural areas are associated with higher rates of type 2 diabetes, more prevalent risk factors for type 2 diabetes, and higher levels of morbidity and mortality.
• The risk factors for type 1 diabetes are still not well understood but studies have shown that genetic predisposition is necessary but not sufficient for the development of type 1 diabetes. Environmental factors that trigger the auto-immune response are also implicated.

Chapter 5 – Diabetes in children and youth

• Diabetes is one of the most common chronic diseases among children and youth.
• Type 1 diabetes remains the main form of the disease in this population, but type 2 diabetes, historically viewed as an adult disease, has been on the rise globally in children and youth for the last two decades.
• An increase in type 1 diabetes has also been documented in different countries, but the reasons are not completely elucidated. In Canada, the rate of type 1 diabetes among one to nine year olds (in whom type 2 diabetes is very rare) has also increased, from 0.1% (or 3,726 cases) in 1998/99 to 0.2% (or 5,201 cases) in 2008/09.
• In 2008/09, more than 3,000 new cases of diabetes (type 1 and type 2) were reported among Canadian children and youth aged one to 19 years, bringing the number of prevalent cases to just under 26,000.
• For both types, the early onset of the disease increases the risk of related complications and lifelong consequences.
• Children and youth with type 1 diabetes are at a greater risk of life-threatening complications because they rely on daily doses of insulin.
• Adolescence can be a particularly difficult time for management of glycemic levels as teenagers take on this responsibility at the same time as hormonal changes affect glycemic levels and impact insulin requirements.

Chapter 6 – Diabetes among First Nations, Inuit, and Métis populations

• The Aboriginal population in Canada is a diverse group composed of individuals of First Nations, Inuit and Métis heritage. Diabetes prevalence varies between and within each group according to its unique characteristics.
• It is important to account for the younger age structure in the First Nations, Inuit and Métis populations when comparing the prevalence of diabetes to that of the non-Aboriginal population. Age-standardized rates show the prevalence of diabetes was 17.2% among First Nations individuals living on-reserve, 10.3% among First Nations individuals living off-reserve, and 7.3% among Métis, compared to 5.0% in the non-Aboriginal population. The age-standardized prevalence rate of diabetes in Inuit populations was comparable to the one seen in the general Canadian population.
• Aboriginal individuals are generally diagnosed at a younger age than non-Aboriginal individuals, and Aboriginal females experience higher rates of gestational diabetes than non-Aboriginal females. Complications of diabetes are also more frequently seen among the Aboriginal population than in the non-Aboriginal population.
• The socio-cultural, biological, environmental and lifestyle changes seen in the First Nations, Inuit and Métis populations in the last half century have contributed significantly to increased rates of diabetes and its complications.