Prevalence of isolated systolic hypertension in the population over 55 years old. Results from a national study.

INTRODUCTION: Isolated systolic hypertension (ISH) is an important risk factor for cardiovascular events (myocardial infarction and stroke) and premature mortality, particularly in the elderly population. Among this population, it is an even better predictor of morbidity and mortality than diastolic blood pressure (BP). This cooperative survey was promoted by the World Hypertension League, Associação Portuguesa de Hipertensão, Instituto Nacional de Cardiologia Preventiva, Sociedade Portuguesa de Cardiologia, Sociedade Portuguesa de Geriatria, Sociedade Portuguesa de Medicina Intema, and Direcção Geral de Saúde, with the collaboration of Servier Portugal. OBJECTIVES: The aim of this survey was to evaluate the prevalence of ISH within the Portuguese elderly population (aged 55+) during the year 2000, compared and together with other countries, in order to estimate its worldwide prevalence. Secondary objectives were to investigate demographic factors related to ISH (age, gender and other cardiovascular risk factors) and to analyze the effects of repeated blood pressure measurements on prevalence and on postural variations in blood pressure. METHODS: We performed a survey including 108 primary care centers. General practitioners were invited to include the first consecutive 15 patients aged over 55 years. Subjects were be selected over a period of one week and had to agree to attend three visits. All blood pressure measurements were to be performed in accordance with the standards of the 7th Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI). 1031 subjects were included in this survey. CONCLUSIONS: We concluded that ISH prevalence ranges between 20.3% in primary" care patients and 35% in the community, using mean values of both systolic and diastolic BP. ISH prevalence is higher among women; it increases with age, decreasing slightly after the age of 70. Risk factors include gender, age and family history of hypertension. The predictive value for ISH diagnosis is 100% and 65% with methods ISH-1 and ISH-2 respectively, with positive predictive value of 51.05% and 63% for ISH-1 and ISH-2 respectively. Orthostatic hypotension prevalence is higher at 5 minutes than at 2 minutes and is higher among elderly subjects. The prevalence of untreated hypertension in the Portuguese population aged over 55 years, according to the WHO/ISH criteria, was 44.92%.

Prevalence, awareness, treatment and control of hypertension in Portugal. The PAP study.

The objective of this study was to estimate the prevalence and distribution of hypertension and to determine the level of awareness, treatment, and control of hypertension in the Portuguese adult population. The study was conducted in 2003, using a multistage cluster sampling method to select a representative national sample. A total of 5023 adults, aged 18 to 90 years, were examined. Three blood pressure measurements were obtained by trained observers using an OMRON M4-1 sphygmomanometer after a 5-minute seated rest. Information on history of hypertension and use of antihypertensive medication was obtained using a standard questionnaire. Hypertension was defined as mean systolic blood pressure > or =140 mmHg and/or diastolic blood pressure > or =90 mmHg, or use of antihypertensive medication. Overall, 42.1% of the Portuguese adult population aged 18 to 90 years, representing 3,311,830 people, would have hypertension. The age-specific prevalence of hypertension in the three age-groups studied--under 35 years, 35-64 years, and over 64 years--was 26.2%, 54.7% and 79% in men and 12.4%, 41.1% and 78.7% in women respectively. Among hypertensive subjects, only 46.1% were aware of their high blood pressure, 39.0% were taking antihypertensive medication, and 11.2% had their blood pressure controlled (<140/90 mmHg). Our results indicate that hypertension is highly prevalent in Portugal. The percentages of hypertensives who are aware of their condition, are being treated, and whose hypertension is controlled are unacceptably low. These results underscore the urgent need to develop national strategies to improve prevention, detection, and treatment of hypertension in Portugal.