Report from the National Diabetes Surveillance System: Diabetes in Canada, 2009

[Table of Contents] [Next]

Executive Summary

Diabetes

• Diabetes is a chronic condition that stems from the body's inability to produce and/or properly use insulin. The body needs insulin to use sugar as an energy source. Diabetes can lead to serious complications and premature death. However, if someone has diabetes, steps can be taken to control the disease and lower the risk of complications.

National Diabetes Surveillance System (NDSS)

• The NDSS is a collaborative network of provincial and territorial diabetes surveillance systems, supported by the Public Health Agency of Canada. It was created to improve the breadth of information about the burden of diabetes in Canada so that policymakers, researchers, health practitioners, and the general public can make better public and personal health decisions. The NDSS regularly seeks advice from Aboriginal groups, non-governmental organizations, and researchers in order to enhance and interpret the information from the system.
• The NDSS surveillance system summarized data about residents of Canada who have used the Canadian health care system. If there was sufficient evidence of use due to diabetes it was assumed that a person had diagnosed diabetes. The minimum requirement was at least 1 hospitalization or 2 physician claims, with a diabetes specific code(s), over a two year period.

NDSS Highlights

• This report features the most recent data available, fiscal year 2006-07, as well as some trend data back to 2000-01. Data from Nunavut were not available for this report and data from Quebec were not available for certain statistics which are noted in the applicable section.

Prevalence

• The age-standardized prevalence of diagnosed diabetes increased by 21% from 2002-03 to 2006-07.
• Approximately 2 million Canadians aged one and older—6.2% or about one in 16 people—were living with diagnosed diabetes in 2006-07; 5.9% of girls/women and 6.6% of boys/men (prevalence).
• Projections indicate that by 2012 almost 2.8 million Canadians will be living with diagnosed diabetes—an estimated annual percent increase of about 6% per year with an overall increase of about 25% from 2007.
• After adjusting for differences in age distributions between provinces and territories, the age-standardized prevalence of diagnosed diabetes was found to be higher in: Newfoundland and Labrador, Nova Scotia, Manitoba, and New Brunswick. Prevalence was lower in the west: Alberta, British Columbia, and Saskatchewan. The prevalence for Ontario was higher than the national average, and for Quebec, prevalence was lower than the national average. The prevalence of obesity, among the provinces and territories, followed a similar pattern; lower in the western provinces than the Canadian average.¹

Incidence

• In 2006-07, 211,168 individuals were newly diagnosed with diabetes (6.7 individuals per 1,000 population aged 1 and older) 6.1 per 1,000 girls/women and 7.3 per 1,000 boys/men (incidence).
• The age-standardized rate of new diagnoses of diabetes increased almost 9% between 2002-03 and 2006-07. The increase in obesity and increased screening for diabetes are likely contributing to this increase in the number of people newly diagnosed with diabetes.¹
• The age-standardized prevalence is increasing 3 times faster than the rate of age-standardized incidence rates reflecting the increase in survival of people with diabetes. This is particularly marked among men and women in the 40 to 69 year old age-group.

Mortality Rates²

• Among adults aged 20 years and older, mortality rates of individuals with diabetes were twice as high as those for individuals without diabetes.
• Diagnosed diabetes significantly shortens life expectancy for all ages. For example, women with diagnosed diabetes in the 20 to 39 year age groups had about a 9-year reduction in life expectancy, on average, while men had about an 8-year reduction.

Use of Health Services²

• Younger adults (aged 20 to 49) with diagnosed diabetes had almost twice as many visits to family physicians, and 3 to 4 times as many visits to specialists than individuals without diabetes.
• Adults with diagnosed diabetes had longer hospital stays than individuals without diabetes. For hospitalized adults with diagnosed diabetes, aged 20 to 29 and 35 to 49 years, the number of hospital days was 5 to 6 times and almost 5 times (respectively) the number of hospital days for adults without diabetes.
• Children and adolescents with diagnosed diabetes had about 5 times as many visits to specialists as those without diabetes.
• Hospitalized children and adolescents with diagnosed diabetes, had about 11 times the number of days in hospital as those without diabetes.

 Diabetes and Other Health Problems

• 63% adults³ with diabetes (1.3 million) also had a diagnosis of hypertension—3 times more often than those without diabetes.
• Adults⁴ with diabetes were hospitalized with selected health problems significantly more often than their counterparts without diabetes with selected health problems.
  • about 3 times more often with ischemic heart disease and with heart attack (a subset of ischemic heart disease);
  • almost 4 times more often with heart failure;
  • about 6 times more often with chronic kidney disease;
  • almost 3 times more often with stroke; and
  • almost 19 times more often with lower limb amputations.

British Columbia⁵ First Nations Population

• The age-standardized prevalence of diagnosed diabetes among the First Nations population aged one and older was 6.7% - about 40% higher than that of other British Columbia residents.
• Between 2002-03 and 2006-07 age-standardized prevalence of diagnosed diabetes among the First Nations men and women increased by about 15.5%.

Introduction

Diabetes

Diabetes is a chronic condition that stems from the body's inability to produce and/or properly use insulin. The body needs insulin to use sugar as an energy source. Diabetes can lead to serious complications and premature death. However, controlling the disease can lower the risk of complications.

• Type 1 diabetes occurs when the beta cells of the pancreas are destroyed by the immune system and no longer produce insulin. Individuals with type 1 diabetes rely on an external supply of insulin for the body to function. Type 1 diabetes usually develops in childhood or adolescence and there is no known way to prevent it.
• Type 2 diabetes occurs when the body does not make enough insulin and/or does not respond well to the insulin it makes. People are usually diagnosed with type 2 diabetes after the age of 40, although it is now also being seen in younger adults, as well as children and adolescents.
• Gestational diabetes is a form of diabetes that develops in women during pregnancy and typically disappears after delivery. Gestational diabetes occurs in about 4% of all pregnancies, and increases the risk of developing type 2 diabetes.

The risk of developing type 2 diabetes can be reduced by making healthy lifestyle choices, such as having a healthy diet, losing excess weight and exercising regularly. Weight loss of 5% to 10%—about 4.5 to 9 kg (10 to 20 lbs.) for a 90/kg (200/lb.) person—has been shown to significantly reduce risk.

The management of diabetes depends on the type of diabetes and can include lifestyle modification and/or medications, including insulin. Regular physical activity and healthy weight are important factors for effective management of diabetes. Controlling blood glucose, blood pressure and blood lipids are necessary to reduce other diabetes related health problems. Self-management of diabetes is an essential part of overall care. Effective disease management may help prevent or delay many health problems related to diabetes such as cardiovascular disease, kidney failure, blindness, nerve damage, heart attack, and stroke.

National Diabetes Surveillance System (NDSS)

• The NDSS is a collaborative network of provincial and territorial diabetes surveillance systems, supported by the Public Health Agency of Canada. It was created to improve the breadth of information about the burden of diabetes in Canada so that policymakers, researchers, health practitioners, and the general public can make better public and personal health decisions. The NDSS regularly seeks advice from Aboriginal groups, non-governmental organizations, and researchers in order to enhance and interpret the information from the system.
• This report features the most recent data available, fiscal year 2006-07, as well as some trend data back to 2000-01. Data from Nunavut were not available for this report and data from Quebec were not available for certain statistics which are noted in the applicable section.
• In each province and territory, the health insurance registry database is linked to the physician billing and hospitalization databases. This surveillance system summarized data about residents of Canada who have used the Canadian health care system. If there was sufficient evidence of use due to diabetes it was assumed that a person had diagnosed diabetes. The minimum requirement was at least 1 hospitalization or 2 physician claims, with a diabetes specific code(s), over a 2-year period. The NDSS case criteria were designed to exclude women with gestational diabetes, because it typically disappears after delivery.
• Using administrative data for surveillance, as in the NDSS, often requires a compromise when trying to identify cases of a disease. It is necessary to balance the possibility of not capturing people who have been diagnosed with diabetes in the NDSS database (false-negatives) with the reverse where people who do not have diabetes have been captured by the NDSS using the case criteria (false-positives). Validation studies have indicated that the NDSS case criteria minimize both false-negatives and false-positives in order to depict a relatively accurate picture of diagnosed diabetes in Canada. The database does miss the people who have diabetes but have not yet been diagnosed with the condition.
• Type 1 and Type 2 diabetes represent about 5-10% and 90-95%, respectively, of the total population living with diabetes.⁶ It is not possible with the current dataset to distinguish between diabetes type 1 and 2 due to limitations of the physician billing data and the hospital discharge abstract data. Therefore, it is assumed that the NDSS database reflects the same proportion of type1 and type 2 diabetes.
• Recent changes to the coding procedures for hospitalization data may benefit the system in the future. For example, in the latest version of the International Classification of Disease (ICD) coding system (ICD-10-CA) used by hospitals to record the details of hospitalizations, separate codes for type 1 and type 2 diabetes are provided. It is anticipated that as ICD-10-CA coded hospital data are accumulated and validated, it will be possible to analyze and report rates associated with hospitalization stratified by diabetes type. Also, beginning with the 2006-07 data, the Canadian Coding Standards for ICD-10-CA and CCI, 2009⁷ mandated that all provinces and territories include any information about patients with diabetes in their hospitalization data. This new practice could enable the NDSS to identify more people with diabetes, and find them earlier, from the hospitalization data. This situation will be monitored to determine the effect and magnitude on the data collected by the surveillance system.

---

Footnotes

¹ Public Health Agency of Canada. Obesity in Canada: Snapshot, 2009. URL: http://www.phac-aspc.gc.ca/publicat/2009/oc/index-eng.php
² Data from Quebec were unavailable.
³ Data from Quebec were not available for the rate ratio statistic but were estimated for the number of adults with hypertension.
⁴ Data from Quebec were not available for the rate ratio statistics, but were included in the number of adults with diabetes who also had other health problems.
⁵ Diabetes refers to a modified NDSS case criteria, used in British Columbia, for this study. Refer to the NDSS methods for more information.
⁶ Public Health Agency of Canada. Diabetes in Canada: Second Edition. URL: http://www.phac-aspc.gc.ca/publicat/dic-dac2/english/05contents-eng.php
⁷ Canadian Institute for Heath Information. Canadian Coding Standards for ICD-10:CA and CCI, 2009. URL: http://secure.cihi.ca/cihiweb/dispPage.jsp?cw_page=RC_382_E

[Table of Contents] [Next]