Prevalence, incidence, awareness and control of hypertension in the province of Quebec: Perspective from administrative and survey data

OBJECTIVES: Hypertension is a major risk factor for cardiovascular diseases. Nearly one adult in four was diagnosed with hypertension in 2007-2008 in Canada. One of the objectives of this study was to determine whether the prevalence of hypertension in Quebec as assessed using administrative data is comparable to that specifically measured, especially for the elderly population. METHODS: Trends in prevalence, incidence and mortality were examined using the Quebec Integrated Chronic Disease Surveillance System built from grouping numerous administrative databases from 1996-1997 to 2009-2010. Blood pressure measurements, hypertension prevalence, awareness and control were obtained in 1,706 Quebecers in the combined cycles of the Canadian Health Measures Survey. RESULTS: Using administrative databases, 23.6% [95% confidence interval, 23.5-23.6] of the Quebec population (n=1,433,400) aged >= 20 years was diagnosed with hypertension in 2009-2010, an increase of 32.1% compared to 2000-2001. The incidence decreased by 27.3%. Among people aged >= 65 years, the prevalence rose to 69.0% [95% CI: 68.8-69.2] in women and 61.7% [95% CI: 61.5-61.9] in men. For people aged 20-79 years, the prevalence of hypertension was lower with the administrative data compared to the survey (20.2% and 23.1%, respectively). The level of awareness, treatment and control were 84.3%, 83.1% and 67.9%, respectively. CONCLUSION: The prevalence of hypertension derived from administrative data is comparable to that obtained with a health measured survey. Elderly women (>= 65 years) are a very high-risk subgroup. The levels of awareness, treatment and control of hypertension in Quebec are very high.