Table 1 Characteristics of the studies included in the meta-analysis
From: Association between acute mountain sickness (AMS) and age: a meta-analysis
Study | Max altitude (m) | Male/Female (n) | Sample size (n) | LLS or CAS cut-off value | Age range (mean, year) | Age (year) | P | Subject origin | Ascent mode | Ascent duration | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
AMS | Non-AMS | Sum | AMS | No AMS | |||||||||
Hackett, 1976 [2] | 4243 | – | 146 | 132 | 278 | Arbitrary symptom score ≥ 2 | 18–71(33) | 31.4 ± 9.7 | 35.2 ± 13.3 | 0.029 | Britain, USA, France, Germany, Switzerland, Japan, Other | Plane, Trek | 4d |
Wagner, 2006 [37] | 4419 | 266/93 | 120 | 239 | 359 | LLS ≥ 3 | 10–76(39.2) | 34.40 ± 12.81 | 41.71 ± 14.71 | < 0.0001 | USA | Trek | 1–3 d |
Mairer, 2009 [38] | 3500 | 316/106 | 70 | 361 | 431 | LLS ≥ 4 | -- (37.4) | 38.4 ± 11.1 | 37.2 ± 13.1 | 0.20 | Austria | Trek | – |
Mairer (a), 2010 [39] | 3454 | 64/11 | 30 | 45 | 75 | LLS ≥ 4 | -- (34.7) | 35.1 ± 10.7 | 34.5 ± 10.2 | 0.79 | Austria | Trek | – |
Mairer (b), 2010 [39] | 3817 | 63/17 | 28 | 52 | 80 | LLS ≥ 4 | -- (36.8) | 36.2 ± 12.2 | 38.1 ± 10.4 | 0.47 | Austria | Trek | – |
Karinen, 2012 [40] | 5600 | 34/22 | 24 | 12 | 36 | LLS ≥ 3 | 24–45(32) | 33 ± 7 | 30 ± 5 | > 0.05 | Finland | Trek | 7–17 d |
Wei, 2012 [34] | 4000 | – | 276 | 924 | 1200 | CAS ≥ 5 | 20–50(35) | 35.36 ± 19.54 | 35.80 ± 16.85 | > 0.05 | China | – | – |
Mao, 2012 [35] | 4768 | 135/87 | 71 | 213 | 284 | LLS ≥ 3 | 18–69(40.5) | 43.5 ± 13.5 | 37.8 ± 12.7 | < 0.05 | China | Train | 1.5 h |
You, 2012 [41] | 4300 | 314/0 | 119 | 195 | 314 | LLS > 4 | - (20.2) | 20.08 ± 1.62 | 20.25 ± 1.83 | 0.414 | China | Bus | 4 d |
Harrison, 2013 [42] | 3200 | 55/35 | 30 | 60 | 90 | LLS ≥ 3 | - (35.4) | 33.8 ± 9.2 | 36.2 ± 9.4 | > 0.05 | USA | Plane | < 4 h |
Song, 2014 [36] | 3900 | 73/0 | 37 | 36 | 73 | LLS ≥ 3 | 18–26(20.5) | 20.72 ± 2.21 | 20.33 ± 2.05 | > 0.05 | China | Car | 5 d exposure |
Wu, 2015 [44] | 3886 | 102/77 | 80 | 99 | 179 | LLS ≥ 3 | 11–13(11.8) | 11.8 ± 0.5 | 11.8 ± 0.4 | NS | China | Bus Walk | 6 h + 2 h |
Bian, 2015 [45] | 3700 | 150/ | 84 | 66 | 150 | LLS ≥ 3 | 18–60(22.2) | 22.77 ± 3.83 | 21.39 ± 2.38 | 0.011 | China | Plane | 2 h |
Ren, 2015 [46] | 4300 | 31/49 | 35 | 45 | 80 | LLS > 3 | 20–50(38.4) | 38.1 ± 11.8 | 38.6 ± 8.3 | 0.829 | China | Plane, bus | 6 h |
Li (a), 2015 [47] | 3700 | 752/0 | 461 | 291 | 752 | LLS ≥ 3 | 18–45(22.9) | 23.0 ± 3.9 | 22.8 ± 3.9 | 0.475 | China | Plane | 2.5 h |
Li (b), 2015 [47] | 4400 | 267/0 | 104 | 163 | 267 | LLS ≥ 3 | 18–45(22.0) | 22.2 ± 2.5 | 21.8 ± 2.3 | 0.162 | China | Car | 3 h |
Yu, 2016 [48] | 3700 | 176/0 | 95 | 81 | 176 | LLS ≥ 3 | - (23.0) | 23.21 ± 3.96 | 22.78 ± 3.45 | 0.181 | China | Plane | 2 h |