Assessing the quality and effects of hypertension control in populations

The objectives of hypertension control include early detection, treatment and prevention of blood pressure (BP) elevations. In clinical situations, continuous evaluation of an Individual's treatment is an inherent part of normal follow-up. On the level of populations, however, evaluation of hypertension control calls for specially designed action. Evaluation is needed for several reasons; these are, inter alia, strategic (to improve the method); economic (to upgrade cost-effectiveness); and ethical reasons (to morally justify public action). Since hypertension control in populations is itself a complex process, its evaluation requires, multidimensional approaches. The methodologic experience from three WHO studies of this kind has been reported. These were done in different contexts: (1) evaluation of the effects of a special multicentre programme for hypertension control in populations; (2) long-term monitoring of cardiovascular disease incidence; and (3) a project for the assessment of levels and quality of hypertension control that is taking place spontaneously. In the first study, changes with time were compared in pairs of similar communities, of which one had been exposed to an organized programme for the control of hypertension ('intervention' vs 'reference' community). The second study uses an elaborate system of disease registers and surveys periodically a number of general populations. In the third study the actual level and quality of hypertension control was analysed in different, mostly European, populations; the findings related to the treatment of hypertension were compared with the standards suggested by WHO and ISH; other findings were assessed on the basis of common sense.