Prevalence, awareness, treatment, and control of hypertension: rule of thirds in the Skaraborg project

Abstract

Objective: To describe the prevalence, awareness, and control of hypertension in a Swedish population during the early 2000s to address implications for care and prevention.

Design: A cross-sectional population survey.

Setting: Primary health care in Skaraborg, a rural part of western Sweden.

Subjects: Participants (n =2816) in a population survey of a random sample of men and women between 30 and 75 years of age in the municipalities of Vara (81% participation rate) and Skövde (70%), in western Sweden during 2001-2005.

Main outcome measures: Anthropometric measures, blood pressure, leisure-time physical activity, current smoking, fasting glucose, and cholesterol. Hypertension was defined as ongoing treatment for hypertension, or three consecutive blood pressure readings ≥140 systolic and/or ≥90 mmHg diastolic. Hypertension was considered controlled when the blood pressure was <140/90 mm Hg (both).

Results: The prevalence of hypertension was 20% in both men and women with a steep increase by age. Among hypertensive subjects, 33% were unaware, 36% aware but uncontrolled, and 31% aware and controlled, with no statistically significant differences between men and women. Patients with diabetes had a higher awareness (87% vs. 64%, p <0.001), but the same control rate (56% vs. 44%, p =0.133), when compared with those without diabetes.

Conclusion: A large proportion of subjects with hypertension are still unaware of their condition, or aware but not controlled. It is important to emphasize population-based prevention to reduce the prevalence of hypertension, to perform screening to increase awareness, and to improve implementation of expert guidelines in clinical practice to improve control.

Figure 1.

Proportions of normal blood pressure (1), known hypertension, treatment goals not met (2), known hypertension, treatment goals met (3), and new screening detected hypertension (4), respectively: Distribution by five-year age groups in men and women combined in the Vara-Skövde cohort 2001–2005.

Figure 2.

Factors related to known hypertension in the Vara-Skövde cohort 2001–2005: Associations estimated by logistic regression entering age and study site as covariates and expressed as odds ratios (OR) with 95% confidence intervals.