Altitude, a history of Acute Mountain Sickness (AMS), rate of ascent and lack of acclimatization are some well established risk factors for developing AMS. Another risk factor is cigarette smoking, which is particularly interesting because it is modifiable.
Previous findings in regard to smoking and AMS have been quite variable. A recent study published in the Wilderness & Environmental Journal aims to give insight in this relation with their publication: Smoking increases the Risk of Acute Mountain Sickness.
The study involved a 12 month follow up of a 569 newly hired miners working at an altitude of 3800 to 4500 meters in Kyrgyz Republic. Almost half of the group smokers with a mean consumption of 8 cigarettes a day. 46 cases of AMS were described. Adjusted for age, sex and altitude of permanent residence, cigarette smoking was prospectively associated with AMS (Hazard Ratio 1.9, 95%CI 1.1-3.2 per 10 cigarettes smoked). This risk was higher in the subset of workers with less demanding physical work.
Airflow obstruction caused by smoking is suggested to play a part in the increases risk, raising the question spirometric surveillance for screening purposes and even the role for potential treatment with bronchodilators. Since the current literature on smoking and AMS is so heterogenous we should be cautious to extrapolate the conclusions from this article, based on intermittent altitude exposure of an occupational group, to the mountaineering and trekking population. We have to conclude, though, that identifying a modifiable risk factor for AMS sounds very promising.
Read the full article here.
Vinnikov D, Brimkulov N, Blanc PD. Smoking increases the risk of acute mountain sickness. Wilderness Environ Med. 2015 Jun;26(2):164-72. doi: 10.1016/j.wem.2014.10.006. Epub 2015 Mar 4. PMID: 25747540.