Compliance, electronic monitoring and antihypertensive drugs

Abstract

Hypertension, even of mild-to-moderate severity, is undoubtedly a risk factor for cardiovascular morbidity and mortality. It has been well demonstrated, in numerous studies that have been subjected to meta-analysis, that the introduction of antihypertensive treatment leads to reductions in cardiovascular and cerebrovascular events. These results can be obtained with even a moderate reduction in blood pressure, of the order of 4-5 mmHg in diastolic blood pressure. However, many studies have shown that the percentage of treated hypertensive individuals who have a reduction in blood pressure to normal values of systolic blood pressure/ diastolic blood pressure (< 140/90 mmHg) is of the order of 30%. The reduction in blood pressure data are well correlated with the level of compliance. This compliance can be defined as the adherence by the patient to the directions given by the doctor for medication dosage, and this can be considered as 'good' when it is of the order of 80%. Until recently the examination of compliance relied on questioning the patient, pill counts or ultimately blood sampling for drug levels, which could be used only in research. The use of an electronic pill box with a microprocessor in the cover that records the date and hour each time the box is opened is a precise method of recording compliance. The purpose of such a method is to study overall compliance, which deteriorates as time passes and falls by approximately 50% after 1 year. However, this compliance can be modified and improved if instruction and follow-up are given to the patient. Prescription compliance can be improved by once daily dosing and by instructing for this to be taken in the morning. In contrast compliance is considerably reduced when more than two doses are to be taken each day. Using the pill counting box allows us to describe and focus on different types of patients, ranging from rigidly adherent to completely chaotic. It seems that factors such as age and activity can influence these patterns of compliance.