Choosing a definition of hypertension: impact on epidemiological estimates

OBJECTIVE: To assess the impact of the use of different definitions on epidemiological estimates of hypertension. METHOD: The four most commonly accepted definitions of hypertension were applied to the 2353 subjects of a hypertension population prevalence survey in Québec. RESULTS: Depending on the definition used, the estimated prevalences of hypertension ranged from 9.6 to 19.9%, from 9.3 to 22.5% for men and from 9.9 to 17.4% for women. Successful control ranged from 15.5 to 68.1%. Regardless of the definition employed, lack of case detection was the main barrier to hypertension control, from 73.2 to 77.1% for men and from 34.6 to 62.0% for women. Lack of appropriate treatment or compliance, or both, was a more important barrier to blood pressure control for women than for men. CONCLUSION: This study shows that the choice of a definition has an important impact on clinically and epidemiologically relevant hypertension estimates for impending clinical and public health decisions.