ABC | Volume 114, Nº6, June 2020

Original Article Velten Orthostatic hypotension and pressure variation: ELSA Arq Bras Cardiol. 2020; 114(6):1040-1048 Ethics The ELSA-Brazil received approval from the Research Ethics Committees of the institutions involved, and all participants signed a consent form. 16 Results The prevalence of OH by sex, age range, race/color, and level of schooling in the study population and the subsample is shown in Table 1. The average age of the total study population was higher than that of the subsample (52.1 ± 9 years versus 49.1 ± 8.2 years, respectively; p < 0.01). The prevalence of OH in these two groups was 2.0% (95% CI: 1.8 –2.3) and 1.5% (95% CI: 1.3 – 1.8), respectively. In the entire population, considering individuals under the age of 60 and those 60 or over separately, the prevalence of OH was 1.6% (95% CI: 1.4 – 1.9) and 3.2% (95% CI: 2.8 – 4.1), respectively. In the subsample, these values were 1.4% (95% CI: 1.1 – 1.7; average age of 47.2 years) and 2.6% (95% CI: 1.8 – 3.8; average age of 64.3 years), respectively. The effect of age is ever clearer when grouping individuals by decades. It was observed that the prevalence below the age of 55 was practically identical in the total population and the subsample. After this age, the subsample presented a lower prevalence. Another factor that impacted prevalence was level of schooling; there was a progressive increase in prevalence among participants with lower levels, in both the total population and the subsample. Protocol changes were reported in 775 (5.2%) individuals. Of these cases, 33.7% (260 individuals, 1.8% of the total population) reported the occurrence of signs and symptoms suggestive of OH (dizziness, difficulty standing without support, nausea, and rarely vomiting). Protocol changes in other cases generally resulted from physical limitations that complicated performance of the maneuver, use of the arm or the left leg (ABI), and use of the mercury sphygmomanometer. Report of symptoms associated with OH occurred in only 1.4% (95% CI: 1.2 – 1.6) of individuals without OH; this value increased to 19.7% (95% CI: 15.6 –24.6) in individuals with OH and to 43% (95% CI: 33.0 – 53.6) when defining OH as a reduction in both pressures. Average values and SD of SBP and DBP with the postural change maneuver for the entire cohort and the subsample are described by sex and age range in Table 2. It was observed that, on average, pressure variations were positive, with no differences between sexes and age groups. Figure 2A shows pressure variations by range of difference. It was observed that the variation was generally situated from −10 to +10 mmHg for SBP, with increases of up to 10 mmHg in DBP. SBP increased in 66.4% of the population, and DBP increased in 88.0%. Figure 2B contains the histogram of the variations in the subsample. Average values minus two SD and the current reference value are indicated. The variations follow normal and similar distribution, and the current cutoff points are located between two and three SD below the average. The prevalence at 3 minutes, when applying the criterion of a reduction of 30 mmHg for individuals with hypertension was 1.5% (95% CI: 0.3 – 1.7), with a total of 222 participants. Furthermore, with respect to measurement at 3 minutes, Table 1 - Prevalence of orthostatic hypotension by sociodemographic data, ELSA-Brazil (2008 – 2010) Variables Orthostatic hypotension Present Total Prevalence (95% CI*) Study population (n = 14,833) Sex Male 135 6,796 2.0 (1.7 - 2.4) Female 165 8,037 2.0 (1.8 - 2.4) Age range 35 to 44 years 39 3,298 1.2 (0.9 - 1.6) 45 to 54 years 93 5,825 1.6 (1.3 – 2.0) 55 to 64 years 116 4,157 2.8 (2.3 - 3.3) 65 to 74 years 52 1,553 3.3 (2.6 - 4.3) Color/race Black 59 2,342 2.5 (2.0 - 3.2) Mixed 81 4,110 1.9 (1.6 - 2.4) White 139 7,679 1.8 (1.5 - 2.1) Yellow/Indigenous 13 525 2.5 (1.5 - 4.2) Highest level of schooling completed Primary 57 1,883 3.0 (2.3 - 3.9) Secondary 110 5,133 2.1 (1.8 - 2.6) Tertiary 133 7,817 1.7 (1.4 - 2.0) Total 300 14,833 2.0 (1.8 – 2.2) Subsample of the study population† (n = 8,011) Sex Male 56 3,289 1.7 (1.3 - 2.2) Female 66 4,722 1.4 (1.1 - 1.8) Age range 35 to 44 years 33 2,570 1.3 (0.9 - 1.8) 45 to 54 years 50 3,388 1.5 (1.1 - 1.9) 55 to 64 years 30 1,688 1.8 (1.2 - 2.5) 65 to 74 years 9 365 2.5 (1.3 - 4.6) Color/race Black 16 1,223 1.3 (0.8 - 2.1) Mixed 39 2,219 1.8 (1.3 - 2.4) White 63 4,181 1.5 (1.2 - 1.9) Yellow/Indigenous 3 284 1.1 (0.4 - 3.1) Highest level of schooling completed Primary 15 645 2.3(1.4 - 3.8) Secondary 39 2,643 1.5 (1.1 - 2.0) Tertiary 68 4,723 1.4 (1.1 - 1.9) Total  122 8,011 1.5 (1.3 - 1.8) *95% CI: 95% confidence interval; †: Study population following the exclusion of patients with hypertension, diabetes, history of heart failure, severe coronary disease, infarction, and stroke, as well as those using anti-hypertensive medication. 1042