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This question in some ways is related to this question asked by JollySin.

When I did my first Himalayan trek, my guide there had told me that those with a low blood pressure (BP) are more susceptible to Acute Mountain Sickness (AMS). The logic according to him was that low BP along with high altitude will result in the blood flow to the brain reducing further and the symptoms of AMS are more likely to occur at an earlier stage in those with a low BP.

Hence, is there a scientific relationship between BP(either low or high) and AMS?

Please try to include references for the answers.

  • Surely blood pressure, as opposed to just PPO2, may have an impact on AMS? Acute exposure increases blood pressure; as a result those with hypertension are warned against altitude exposure. However, acclimatised individuals generally display lower resting values due to a vasodilatory effect of hypoxia on vascular smooth muscle. If anything, hypotension may be protective in the initial stages... but maybe a hindrance after acclimatisation? – user7850 Sep 25 '15 at 14:22
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There is no documented scientific relationship between individual blood pressure and AMS. Furthermore, your guide appears to be completely mis-informed as to the mechanics of AMS. The most common symptom of AMS - a roaring headache - is caused by swelling of the brain as the body attempts to make up for reduced oxygen in the blood by pumping harder and faster (hence an increased heart rate). See: http://www.altitudemedicine.org/index.php/altitude-medicine/learn-about-altitude-sickness

Incidentally, high blood pressure would put one at risk for cardiac arrest, not AMS, when travelling quickly to high altitudes. See: http://www.altituderesearch.org/traveling-to-altitude/113

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    The possibility of brain getting less oxygen due to low blood pressure seems possible. Why completely rubbish his claim? If thought from a common sense perspective, it looks feasible that someone with low BP might face symptoms early. I might be wrong. Pardon me if I am. – Ricketyship Dec 20 '13 at 17:55
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    I appreciate the common sense aspect of it - I get it - but you asked if there was a scientific relationship between BP and AMS. I dispute the possibility that low blood pressure makes one more susceptible to AMS because the key factor is the oxygen saturation level in the blood, which is not related to blood pressure. – Andrew Dec 22 '13 at 23:21
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    @Andrew: ...because the key factor is the oxygen saturation level in the blood, which is not related to blood pressure. This statement of yours, Do you think that Human Cardiovascular system is so simple and straight forward to understand? – WedaPashi Jan 7 '14 at 6:01
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    @unsung - Given Pulmonary Oedema is caused by the fluid leaking though the lung linings and cerebral oedema fluid into the brain, a reasonable hypothesis would be low blood pressure would reduce the risk of the most serious effects of AMS. Perhaps you are right, and the bigger headaches lower down cause people with low blood pressure to turn back sooner, making it more likely people with low blood pressure suffer mild AMS and less likely to suffer serious AMS. All these are merely hypothesis, the correct answer "There is no documented scientific evidence"..... – user5330 Apr 10 '16 at 22:29
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I would think not. AMS is caused by lower atmospheric pressure which in turn reduces the number of O2 molecules you get to breathe in. Your own personal blood pressure has nothing to do with the number of O2 molecules available to breathe.

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I have low blood pressure, 90/60 read to me just one week prior to going mountain hiking in Palm Springs California (8,500 ft. elevation). I did not experience the tiredness or lack of oxygen I thought that I would. I seemed to have the same energy as I usually have without any adverse symptoms associated to what many would complain as thinner air at that height. My thinking was that it was due to my lower blood pressure since it was explained to me that since my blood was able to efficiently carry more oxygen with less pumping from my heart, the result lower pressure was needed to supply oxygen to my cells. If the air is thinner, then my heart already pumping oxygen efficiently, would only have to pump a little harder to increase the oxygen level.

protected by imsodin Oct 16 '16 at 10:57

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