ABC | Volume 110, Nº6, June 2018

Original Article Marui et al Blood pressure variables in Duchenne muscular dystrophy Arq Bras Cardiol. 2018; 110(6):551-557 Table 3 – Distribution of the blood pressure variables (office and ABPM) according to age groups Age groups (years) 3-5 years n = 3 6-8 years n = 15 9-11 years n = 18 12-14 years n = 7 15-17 years n = 3 Office SBP* (mm Hg) 117.3 ± 17.0 118.3 ± 14.6 118.2 ± 22.2 119.8 ± 18.2 123.3 ± 12.6 Office DBP † (mm Hg) 69.3 ± 9.5 73.2 ± 8.4 76.4 ± 16.6 71.4 ± 9.1 74.3 ± 4.5 ABPM: 24h SBP (mm Hg) 122.6 ± 20.0 117.7 ± 15.6 119.3 ± 19.6 117.4 ± 8.3 114.3 ± 8.5 ABPM: 24h DBP (mm Hg) 73.3 ± 10.1 71.2 ± 15.6 71.2 ± 13.3 71.7 ± 15.1 69.3 ± 5.9 ABPM: wakefulness SBP (mm Hg) 125.0 ± 19.5 121.0 ± 13.7 121.3 ± 19.8 120.1 ± 8.3 117.3 ± 6.5 ABPM: wakefulness DBP (mm Hg) 76.7 ± 13.0 75.5 ± 8.7 71.4 ± 13.6 74.8 ± 8.3 73 ± 4.4 ABPM: sleep SBP (mm Hg) 119 ± 20.1 111.7 ± 18.1 114.2 ± 19.8 110.4 ± 10.8 109 ± 8.9 ABPM: sleep DBP (mm Hg) 66.7 ± 10.7 61.2 ± 18.7 66.2 ± 13.8 62.9 ± 6.7 59.7 ± 8.1 24h SBPL ‡ (> 50%), n (%) 2 (66.6) 5 (33.3) 7 (38.9) 0 (0) 0 (0) 24h DBPL § (> 50%), n (%) 1 (33.3) 7 (46.7) 7 (38.9) 3 (21.4) 0 (0) Wakefulness SBPL (> 50%), n (%) 2 (66.6) 5 (33.3) 6 (33.3) 0 (0) 0 (0) Wakefulness DBPL (> 50%), n (%) 1 (33.3) 5 (33.3) 5 (27.8) 1 (14.3) 0 (0) Sleep SBPL (> 50%), n (%) 2 (66.6) 7 (46.7) 4 (22.2) 0 (0) 0 (0) Sleep DBPL (> 50%), n (%) 1 (33.3) 2 (13.3) 3 (16.7) 1 (14.3) 0 (0) SBP * : systolic blood pressure; DBP † : diastolic blood pressure; SBPL ‡ : systolic blood pressure load; DBPL § : diastolic blood pressure load. Data presented as numbers (n) and percentages; and mean ± standard deviation. The median ND was lower than 10% for SBP and higher than 10% for DBP in all age groups. It is worth noting that 68% of the boys had no 10% ND for SBP. In adults, the absence of ND is considered a risk factor for target-organ damage, in addition to increasing the cardiovascular risk of hypertensive and normotensive individuals. Although the use of corticosteroid can lead to weight gain and BP elevation, it is the only drug that can delay the progression of muscle weakness, reduce the development of scoliosis, and delay respiratory failure. Its mechanism is based on the hypothesis that its anti‑inflammatory property and immunosuppressive action promote the proliferation of myoblasts and a reduction in necrosis. 25 Our study showed no association of corticosteroid use and AH, blood pressure load elevation and ND. Although a significant part of the boys was on prednisone, its administration was intermittent and on the first days of the month. However, if corticosteroid did not influence BP behavior, what was the factor responsible for the elevated number of hypertensives and BP measurements out of the normal range Table 4 – Distribution of the participants with Duchenne muscular dystrophy according to blood pressure classification on ABPM during 24hours, wakefulness and sleep Classification 24h ABPM n (%) Wakefulness ABPM n (%) Sleep ABPM n (%) Normal 13 28.3 17 36.9 16 34.8 Normal with BPL* > 25% 2 4.3 1 2.2 1 2.2 Prehypertension 6 13.0 4 8.7 7 15.2 Prehypertension without increased BPL 4 8.7 0 0 0 0 White coat SAH † 9 19.6 10 21.7 6 13 Masked hypertension 1 2.2 2 4.3 3 6.5 Masked hypertension with SBPL ‡ > 50% 1 2.2 1 2.2 2 4.3 Severe SAH 11 23.9 10 21.8 8 17.4 High wakefulness or sleep SBP § without increased BPL 0 0 1 2.2 0 0 SAH only on ABPM 0 0 0 0 2 4.3 SAH with SBPL < 25% 0 0 0 0 1 2.2 Total 46 100 46 100 46 100 BPL * : blood pressure load; SAH † : systemic arterial hypertension; SBPL ‡ : systolic blood pressure load; SBP § : systolic blood pressure. Data presented as numbers (n) and percentages. 554