Juvenile idiopathic arthritis in Canada

Highlights from the Canadian Chronic Disease Surveillance System

The most common type of arthritis among children and adolescents is juvenile idiopathic arthritis (JIA).^{Footnote 1Footnote 2} JIA encompasses seven categories of chronic inflammatory arthritis, which begin before the age of 16 years and persist for more than six weeks.^{Footnote 3} While there is no cure for JIA, an effective management strategy, with the goal of disease remission with full function and no painful or swollen joints, can help improve an individual's functional ability and productivity in daily life.

The Public Health Agency of Canada (PHAC), in collaboration with all Canadian provinces and territories, conducts national surveillance of JIA to support public health action. This fact sheet presents an overview of diagnosed JIA data from the Canadian Chronic Disease Surveillance System (CCDSS). For further information, refer to What's in the data?

What is juvenile idiopathic arthritis?

Juvenile idiopathic arthritis (JIA) is a general term covering all categories of chronic inflammatory joint diseases starting before the age of 16 years.^{Footnote 3} The first signs often appear in the joints and surrounding tissues, and present as joint pain, swelling, and stiffness. The frequency of other signs, including fever, swollen lymph nodes, rash, and other findings, vary across the categories.^{Footnote 4} In some cases, JIA can affect other organs, such as the eyes, skin, lungs, heart or gastrointestinal tract. Similar to other types of chronic autoimmune disease, children can move in and out of active and inactive states of the disease.

How many Canadians live with JIA (prevalence) and how many are newly diagnosed each year (incidence)?

Approximately 6,200 (0.10%) Canadians aged 15 years and younger live with diagnosed JIA and about 1,000 (17.1 per 100,000 persons per year) were newly diagnosed in 2016–2017. The prevalence and incidence of diagnosed JIA generally increase with age and are higher among females (0.13% and 21.1 per 100,000 persons per year, respectively) compared to males (0.08% and 13.4 per 100,000 persons per year, respectively) (Figures 1 and 2).

What are the trends over time?

Between 2000–2001 and 2016–2017, the age-standardized prevalence of diagnosed juvenile idiopathic arthritis increased among males (from 0.04% to 0.08%) and females (from 0.07% to 0.13%) (Figure 3). During the same time period, the age-standardized incidence of diagnosed juvenile idiopathic arthritis increased from 9.6 to 13.4 per 100,000 persons per year in males and from 15.2 to 21.2 per 100,000 persons per year in females.

How can juvenile idiopathic arthritis be managed?

As with many autoimmune diseases, the cause of juvenile idiopathic arthritis is not well understood. However, it is likely related to a combination of genetic factors, environmental exposures, and other factors.^{Footnote 5} While there is no cure for juvenile idiopathic arthritis, early diagnosis followed by an effective management strategy can help improve an individual's functional ability and productivity in daily life. Medication treatment plans aimed at reducing pain and inflammation are key to controlling the disease and improving function. The treatment plan also often includes physiotherapy and occupational therapy along with regular exercise. Children diagnosed with juvenile idiopathic arthritis benefit from a multidisciplinary team, including paediatric rheumatologists, rheumatology nurses, pharmacists, physiotherapists and occupational therapists, optometrists and ophthalmologists, in addition to their primary care physician. Dieticians and social workers may also be part of the team.^{Footnote 4}

What do national data on juvenile idiopathic arthritis tell us?

• The number of Canadians aged 15 years and younger living with diagnosed juvenile idiopathic arthritis is increasing over time.
• The prevalence and incidence of diagnosed juvenile idiopathic arthritis generally increase with age and are higher among females compared to males.

Acknowledgements

This work was made possible through collaboration between PHAC and all Canadian provincial and territorial governments and expert contribution from the CCDSS Arthritis Working Group. Results and interpretations reported in this fact sheet are those of the authors. No endorsement by the provinces and territories is intended or should be inferred.

How to learn more

Visit: Canada.ca search "arthritis" or "juvenile idiopathic arthritis" or "JIA"

Get data: Canadian Chronic Disease Surveillance System Data Tool

Follow us: @GovCanHealth

Like us: @HealthyCdns

More: visit the Arthritis Society