Incidence: Report from the Canadian Chronic Disease Surveillance System: Hypertension in Canada, 2010

Adults with Newly Diagnosed Hypertension (Incidence) ^{Footnote 1}

• In 2006/07, 450,029 adults were newly diagnosed^{Footnote 2} with hypertension (22.1 per 1,000 population aged 20 years and older, 21.6 per 1,000 women and 22.7 per 1,000 men) (Table 1).^{Footnote 2}
• Overall, age-standardized incidence rates of diagnosed hypertension remained stable throughout the surveillance period with incidence rates of 26.2 per 1,000 in 1998/99 and 25.8 per 1,000 in 2006/07. During that period, incidence rates declined slightly in women and increased slightly in men (Figure 7).
• The rate of newly diagnosed hypertension rose with increasing age (Figure 8). For example, the rate was 5.6 per 1,000 for adults aged 30 to 34 and increased almost 6 times to 30.7 per 1,000 for adults aged 50 to 54.
• The rate of newly diagnosed hypertension was higher in men than women below the age of 70; however, this trend was reversed after age 70 with higher rates in women than men (Figure 8).
• The age-standardized incidence rates of diagnosed hypertension were higher in Yukon (37.7 per 1,000) and the Atlantic provinces (26.5 per 1,000 to 35.3 per 1,000) and lower in Ontario (24.7 per 1,000) and the Northwest Territories (25.0 per 1,000).
• In 1998/99, Yukon had the lowest age-standardized rate of newly diagnosed hypertension among all provinces and territories (20.0 per 1,000) (data not shown). However, this rate increased significantly to 37.7 per 1,000 in 2006/07, which was greater than the Canadian national rate in 2006/07 (25.8 per 1,000) (Figure 9), crude incidence rates are presented in (Table 3). This may reflect a true increase in incidence, improved diagnosis of hypertension in this territory, or improvements in the way hypertension is coded in claims data. In fact, in 1998 in Yukon, a large proportion of claims did not have the reason for the visit or diagnosis coded in the system. Following the implementation of a new claim system, more claims are being coded using the ICD coding system. The lower number of new cases of diagnosed hypertension that were documented in the earlier years likely had an impact on the lower prevalence of diagnosed hypertension in Yukon during the years under surveillance as prevalent conditions are cumulative. Ongoing tracking of hypertension with the addition of future years data will provide a better sense of the prevalence of hypertension in the Yukon.