Could living at high altitudes affect your chance of suffering a stroke? This intriguing question is at the heart of a new study in open-access journal Frontiers in Physiology.

生活在高海拔地区会影响你中风的几率吗?这个有趣的问题是《生理学前沿》开放获取期刊上一项新研究的核心。

The study is the first to examine the incidence of stroke-related hospitalization and death in people living at four different elevations in Ecuador, and includes data gathered over 17 years on more than 100,000 stroke patients. Strikingly, the study finds that people living at higher altitudes have a lower risk of stroke and stroke-related death, and that this protective effect is strongest at between 2,000 and 3,500 meters.

这项研究首次调查了厄瓜多尔四个不同海拔地区人群中风相关住院和死亡的发生率，包括17年来收集的100000多名中风患者的数据。令人惊讶的是，这项研究发现，生活在高海拔地区的人患中风和中风相关死亡的风险更低，这种保护作用在2000至3500米之间最强。

Stroke is a leading cause of death and disability worldwide. A stroke typically occurs because of a blockage, such as a blood clot, in one of the arteries supplying blood to or within the brain. You may be familiar with some of the most common lifestyle and health factors that contribute to stroke risk, including smoking, high blood pressure, high cholesterol, and lack of physical activity. However, there is another overlooked factor that could also affect your stroke risk – altitude.

中风是全世界死亡和残疾的主要原因。中风通常是由于向大脑供血或在大脑内供血的动脉之一发生堵塞，如血凝块。你可能熟悉导致中风风险的一些最常见的生活方式和健康因素，包括吸烟、高血压、高胆固醇和缺乏体力活动。然而，还有一个被忽视的因素也可能影响你的中风风险——海拔高度。

Higher altitude means less oxygen availability, so people who have lived on higher ground have adapted to these conditions. However, how this environment affects someone's chances of developing stroke is still unclear. Anecdotal evidence suggests that short-term exposure to low oxygen can contribute to increased blood clotting and stroke risk, but the risk among people who permanently live at high altitude is not clear.

海拔越高意味着氧气供应量越少，所以居住在海拔较高地区的人们已经适应了这些条件。然而，这种环境如何影响某人患中风的几率尚不清楚。传闻证据表明，短期暴露在低氧环境下会增加血液凝结和中风的风险，但长期生活在高海拔地区的人的风险尚不清楚。

Researchers in Ecuador are in a unique position to explore these phenomena, as the presence of the Ecuadorian Andes means that people in the country live at a wide array of altitudes.

厄瓜多尔的研究人员在探索这些现象方面处于独特的地位，因为厄瓜多尔安第斯山脉的存在意味着该国人民生活在不同的海拔高度。

The main motivation of our work was to raise awareness of a problem that is very little explored. That is, more than 160m people live above 2,500 meters and there is very little information regarding epidemiological differences in terms of stroke at altitude. We wanted to contribute to new knowledge in this population that is often considered to be the same as the population living at sea level, and from a physiological point of view we are very different."

我们工作的主要动机是提高人们对一个很少探讨的问题的认识。也就是说，超过1.6亿人生活在2500米以上，关于海拔高度中风的流行病学差异的信息非常少。我们希望为这一人群提供新的知识，这一人群通常被认为与生活在海平面上的人群相同，但从生理学角度来看，我们非常不同。”

Esteban Ortiz-Prado, Study Lead Author and Professor, Universidad de las Americas

埃斯特班·奥尔蒂斯-普拉多，美洲大学首席作者和教授