Smoking, acute mountain sickness and altitude acclimatisation: a cohort study

Abstract

RationaleThe relationship between cigarette smoking and acute mountain sickness (AMS) is not clear. Objective To assess AMS risk and altitude acclimatisation in relation to smoking. Methods 200 healthy non-smokers and 182 cigarette smokers were recruited from Han lowland workers. These were men without prior altitude exposure, matched for age, health status and occupation, who were transported to an altitude of 4525 masl. Measurements AMS, smoking habits, arterial saturation (SpO 2 ), haemoglobin (Hb), lung function and mean pulmonary artery pressure (PAPm) were assessed upon arrival and after 3 and 6 months. Main results Compared with non-smokers, smokers had a lower incidence of AMS and lower AMS scores than non-smokers upon arrival; higher Hb and PAPm associated with lower SpO 2 at 3 and 6 months at altitude; and lower forced expiratory volume in 1 s and maximal voluntary ventilation at 3 and 6 months. Conclusions Smoking slightly decreases the risk of AMS but impairs long-term altitude acclimatisation and lung function during a prolonged stay at high altitude.

Sleep quality changes in insomniacs and non-insomniacs after acute altitude exposure and its relationship with acute mountain sickness

“…Our SaO 2 results are consistent with those of Wu et al7 but contrary to those of Chen et al26 The ascent rate may have accounted for this discrepancy.…”

“…At high altitudes, the sleep quality of the subjects cannot be adequately assessed by the Lake Louise diagnostic criteria for AMS alone. Among the Lake Louise diagnostic criteria for AMS, subjective insomnia is the second most7 or even the most8 common symptom. However, there are only a few studies on the effects of high-altitude exposure on sleep, all of which used small sample sizes and polysomnography 9–11.…”

Association between smoking and the risk of acute mountain sickness: a meta-analysis of observational studies

“…Schneider (2002) [4] used the Environmental Symptom Questionnaire (ESQ) to diagnose AMS using an ESQ cut-off value of 0.70, which corresponded to a Lake Louise Score (LLS) of 4. Wu (2012) [17] did not provide original data regarding age, gender or BMI. MacInnis (2013) [26] did not provide clear data regarding age or BMI.…”

“…Schneider (2002) [4] provided only data regarding the total population of subjects. In addition, we analyzed how the studies defined smoking and found that only one article (Wu (2012) [17]) provided the following clear definition of smoking: “A smoker was someone who smoked 10 or more cigarettes/day for >6 months” …”

“…Therefore, searching for factors that are related to AMS development remains necessary. Wu et al [17] reported that the incidence of AMS was lower among smokers than among non-smokers and that smokers exhibited lower AMS scores than non-smokers. A similar conclusion was reached by Song et al [18].…”