Objective: To determine prevalence, awareness, treatment and control of hypertension and the 24-h sodium excretion (24h-UNa) in the Portuguese adult population and to examine their changes from a similar study done in 2003.

Design and setting: A population-based cross-sectional survey conducted in 2011–2012.

Methods: A multistage-stratified (by age and sex) sampling method was used to select a representative sample of the 18–90-year-old population yielding 3720 participants (52.6% women, 97.1% Caucasians). Hypertension was defined as a SBP of at least 140 mmHg or DBP of at least 90mmHg [average of 2–3 blood pressure (BP) measurements by trained observers with OMRON M6] or reported knowledge or treatment with antihypertensive drugs at the first visit (V1). A complete clinical information was obtained with a standard questionnaire. This procedure was repeated 10–15 days after visit 2 (V2) and 24-h urinary sample was collected for 24h-UNa, 24-h potassium excretion and creatinine excretion.

Results: The overall prevalence of hypertension at V1 was 42.2% (44.4% in men, 40.2% in women) (42.1% in 2003). The age-specific prevalence of hypertension was 6.8, 46.9 and 74.9% in people below 35 years, 35–64 years and above 64 years. Co-morbidities were 2.2–6.3 times more common in hypertensive patients vs. normotensive individuals. Overall, among the hypertensive patients, 76.6% were aware of the hypertension condition, 74.9% were treated and 42.5% were controlled (BP <140/90 mmHg), that is, respectively, 1.7, 1.9 and 3.8 times higher vs. data in 2003, with lower values in men vs. women and younger vs. older people. Global mean BP was 127.4/74.6 [17.7/10.5] vs. 134.7/80.4 [21.2/14.1] mmHg in 2003. From V1 to V2, control of hypertension increased on average by 14.8%. Multivariate analysis showed that age and BMI were independently associated with prevalence of hypertension. 24h-UNa (84% valid urinary samples) was 182.5 [64.7] mmol/day (10.7 g salt/day) and 24-h potassium excretion 75.2 [26.1] mmol/day. 24h-UNa was higher in patients with hypertension than in normotensive individuals (185.4 [64.8] vs. 177.8 [64.5] mmol/day; P < 0.02) and correlated with SBP (r 1⁄4 0.05), age (r 1⁄4 0.08) and BMI (r 1⁄4 0.10) (P < 0.01).