Changes in 24 h ambulatory blood pressure and effects of angiotensin II receptor blockade during acute and prolonged high-altitude exposure: a randomized clinical trial
Changes in 24 h ambulatory blood pressure and effects of angiotensin II receptor blockade during acute and prolonged high-altitude exposure: a randomized clinical trial
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DOI：
10.1093/eurheartj/ehu275
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发表时间：
2014-11-21
影响因子：
39.3
通讯作者：
Mancia, Giuseppe
中科院分区：
文献类型：
--
作者：
Parati, Gianfranco;Bilo, Grzegorz;Mancia, Giuseppe
目的 许多高血压患者前往高海拔地区，但对于急性和长期暴露于低压缺氧条件下的动态血压（ABP）变化和抗高血压药物的疗效知之甚少。特别是，血管紧张素受体阻滞剂在这种情况下的功效尚不清楚。考虑到肾素-血管紧张素系统活性在海拔高度发生变化，这可能具有临床相关性。 HIGHCARE-HIMALAYA 研究评估了在急性和长期暴露于海拔升高的情况下 24 小时 ABP 的变化，以及血管紧张素受体阻断剂在这种情况下的降压功效和安全性。 方法和结果 在一项双盲、平行组试验中，47 名健康、血压正常的低地人被随机服用替米沙坦 80 mg 或安慰剂。在基线和治疗时测量常规血压和动态血压：在海平面 8 周后，以及在急性暴露于 3400 和 5400 海拔的情况下，后者是在抵达后和 12 天后（珠穆朗玛峰大本营）。采集血样检测血浆儿茶酚胺、肾素、血管紧张素和醛固酮。在两组中，暴露于海拔升高都与：(i) 常规血压和 24 小时血压显着逐渐升高，并在暴露于 5400 m 的整个过程中持续存在； (ii)血浆去甲肾上腺素增加并抑制肾素-血管紧张素-醛固酮系统。替米沙坦降低了海平面和 3400 m 处的 24 h ABP（组间差异 4.0 mmHg，95% CI：2.2-9.5 mmHg），但在 5400 m 处没有降低。结论 动态血压随着海拔的升高逐渐升高，3 周后仍保持升高状态。血管紧张素受体阻断在 3400 m 处可维持降血压功效，但在 5400 m 处则不然。
Aim Many hypertensive subjects travel to high altitudes, but little is known on ambulatory blood pressure (ABP) changes and antihypertensive drugs' efficacy under acute and prolonged exposure to hypobaric hypoxia. In particular, the efficacy of angiotensin receptor blockers in this condition is unknown. This may be clinically relevant considering that renin-angiotensin system activity changes at altitude. The HIGHCARE-HIMALAYA study assessed changes in 24 h ABP under acute and prolonged exposure to increasing altitude and blood pressure-lowering efficacy and safety of an angiotensin receptor blockade in this setting.Methods and results Forty-seven healthy, normotensive lowlanders were randomized to telmisartan 80 mg or placebo in a double-blind, parallel group trial. Conventional and Ambulatory BPs were measured at baseline and on treatment: after 8 weeksat sea level, and under acute exposure to 3400 and 5400 maltitude, the latter upon arrival and after 12 days (Mt. Everest base camp). Blood samples were collected for plasma catecholamines, renin, angiotensin, and aldosterone. In both groups, exposure to increasing altitude was associated with: (i) significant progressive increases in conventional and 24 h blood pressure, persisting throughout the exposure to 5400 m; (ii) increased plasma noradrenaline and suppressed renin-angiotensin-aldosterone system. Telmisartan lowered 24 h ABP at the sea level and at 3400 m(between-group difference 4.0 mmHg, 95% CI: 2.2-9.5 mmHg), but not at 5400 m.Conclusion Ambulatory blood pressure increases progressively with increasing altitude, remaining elevated after 3 weeks. An angiotensin receptor blockade maintains blood pressure-lowering efficacy at 3400 m but not at 5400 m.