Prevalence and management of hypertension in primary care in Portugal. Insights from the VALSIM study.

INTRODUCTION

Hypertension (HT) is the most common modifiable risk factor for cardiovascular disease, and HT management and control is of major importance in preventive strategies. However, patterns of antihypertensive (AHT) treatment have never been evaluated in Portugal.

OBJECTIVE

To estimate the prevalence of HT and to characterize its management in a primary care setting, identifying the most frequently used drugs and evaluating regional variations in treatment patterns.

METHODS

The VALSIM study is a descriptive cross-sectional study performed in a primary care setting, involving 719 general practitioners (GPs) and representative of all regions of Portugal. The first two patients aged > or = 18 years consulting their GP on each day were asked to participate, irrespective of the reason for the consultation. After informed consent was obtained, a questionnaire was used to collect sociodemographic, clinical and laboratory data. Two blood pressure (BP) measurements were taken after a 5-minute rest period in a seated position. HT was defined as BP higher than 140/90 mmHg or use of antihypertensive medication.

RESULTS

A total of 16,856 subjects were evaluated (mean age 58.1 +/- 15.1 years; 61.3% women). The prevalence of HT adjusted for age and gender was 42.62% (males: 43.09%, females: 42.19%). Of the 9,189 hypertensive patients under treatment, the proportion receiving one, two or three or more drug classes was 47.62%, 36.16% and 16.22% respectively. The classes most frequently used in monotherapy were angiotensin receptor blockers (ARBs, 16.9%), angiotensin-converting enzyme inhibitors (ACEIs, 14.41%) and diuretics (5.85%). The most common associations of two classes were ARB-diuretic (11.82%), ACEI-diuretic (11.79%), ACEI-calcium channel blpcker (CCB, 2%), CCB-diuretic (1.81%) and ARB-CCB (1.53%). The most frequently used AHT drugs were diuretics (47.4%), ARBs (43%) and ACEIs (39.2%). CCBs were used in 18.9% and beta-blockers in 16.2% only. Different patterns of treatment were identified according to gender, age and region of residence. Diuretics were used more in the elderly, women, and in the Azores (61.9%) and the Alentejo (58.3%). ARBs were used preferentially in middle-aged patients, men and in the Northern region (48.6%).

CONCLUSIONS

There is considerable regional variation in treatment patterns. The proportion of hypertensive patients under monotherapy is still very high. Increasing the use of combination antihypertensive therapy would probably improve HT control in the population. Furthermore, increased use of CCBs would probably also be useful, as they are used less than would be expected, compared to other European countries.