Table 4.
Results on measures of lung function before and after the use of an e-cigarette (or conventional cigarette, where specified). Results are shown as mean ± standard deviation.
| SpO2 (T0)% | SpO2 (T1)% | FEV1 T0 %pred or L or effect size [95% CI] | FEV1 T1 %pred or L or effect size [95% CI] | FEV1 T2 %pred or L or effect size [95% CI] | FEV1/FVC (T0) %obs or L or effect size [95% CI] | FEV1/FVC (T1) %obs or L or effect size [95% CI] | FEV1/FVC (T2) %obs or L or effect size [95% CI] | Airway Resistance (T0) kPa L−1 sec−1 | Airway Resistance (T1) kPa L−1 sec−1 | Airway Conductance (T0) sec−1 kPa−1 | Airway Conductance (T1) sec−1 kPa−1 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Palamidas 2013 | ||||||||||||
| Smokers n = 51 | - | - | - | - | - | - | - | - | 0.284 ± 0.13a | 0.308 ± 0.14a | 1.197 ± 0.50a | 1.060 ± 0.42a |
| Nonsmokers (11 mg§) n = 9 | - | - | - | - | - | - | - | - | 0.246 ± 0.07a | 0.292 ± 0.05a | 1.313 ± 0.22a | 1.109 ± 0.18a |
| Nonsmokers (0 mg§) n = 10 | - | - | - | - | - | - | - | - | 0.247 ± 0.03a | 0.333 ± 0.08a | 1.213 ± 0.29a | 0.944 ± 0.18a |
| Ferrari 2015 | ||||||||||||
| Smokers n = 10 vs Nonsmokers CC n = 10 | - | - | −1 [−6.1 to 4.1] | - | - | 2 [−2.0 to 6.1] | - | - | - | - | - | - |
| Smokers n = 10 vs Nonsmokers EC n = 10 | - | - | −2.1 [−5.7 to 1.6] | - | - | −0.1 [−9.8 to 3.0] | - | - | - | - | - | - |
| Palamidas 2017 | %pred | %pred | ||||||||||
| COPD Smokers n = 16 | 96.4 ± 1.9a | 95.8 ± 1.8a | 69 ± 18 | - | - | 59 ± 10 | - | - | 0.43 ± 0.18 | 0.47 ± 0.17 | 0.54 ± 0.19 | 0.52 ± 0.19 |
| Asthma Smokers n = 11 | 97.2 ± 1.5 | 96.6 ± 1.4 | 93 ± 14 | - | - | 79 ± 11 | - | - | 0.38 ± 0.13a | 0.40 ± 0.11a | 0.84 ± 0.31 | 0.80 ± 0.33 |
| Healthy Smokers n = 28 | 98.2 ± 1.0a | 97.1 ± 1.5a | 102 ± 15 | - | - | 81 ± 6 | - | - | 0.29 ± 0.12a | 0.31 ± 0.13a | 1.16 ± 0.47a | 1.03 ± 0.40a |
| Nonsmokers (11 mg§) n = 9 | 97.4 ± 2.1 | 97 ± 0.7 | 114 ± 16 | - | - | 82 ± 2 | - | - | 0.25 ± 0.07a | 0.29 ± 0.06a | 1.31 ± 0.22a | 1.11 ± 0.18a |
| Nonsmokers (0 mg§) n = 12 | 98.4 ± 0.9 | 98.4 ± 0.5 | 104 ± 10 | - | - | 86 ± 4 | - | - | 0.24 ± 0.04a | 0.32 ± 0.08a | 1.20 ± 0.27a | 0.95 ± 0.18a |
| Boulay 2017 | L | L | L | L | ||||||||
| Healthy Nonsmokers n = 20 | 97 ± 3 | 98 ± 1 | 3.9 ± 0.7 | 3.9 ± 0.7 | - | 0.80 ± 0.05 | 0.81 ± 0.05 | - | - | - | - | - |
| Asthma Nonsmokers n = 10 | 98 ± 1 | 98 ± 1 | 3.4 ± 0.4 | 3.4 ± 0.4 | - | 0.78 ± 0.08 | 0.79 ± 0.08 | - | - | - | - | - |
| Coppeta 2018 | L | L | L | L | L | L | ||||||
| Nonsmokers (CC) n = 30* | - | - | 3.53a,b | 3.48a | 3.51b | 82.2a,b | 81.7a | 81b | - | - | - | - |
| Nonsmokers (EC) n = 30* | - | - | 3.55a | 3.51a | 3.53 | 82.1a | 81.6a | 81.5 | - | - | - | - |
| Staudt 2018 | %pred | %pred | %obs | %obs | ||||||||
| Nonsmokers Nicotine n = 7 | 99 ± 1 | 99 ± 1 | 112 ± 15 | 113 ± 11 | - | 81 ± 3 | 83 ± 3 | - | - | - | - | - |
| Nonsmokers Non-Nicotine n = 3 | 99 ± 2 | 98 ± 1 | 103 ± 9 | 91 ± 8 | - | 81 ± 4 | 76 ± 4 | - | - | - | - | - |
| Nonsmokers Total Cohort n = 10 | 99 ± 1 | 99 ± 1 | 110 ± 14 | 107 ± 15 | - | 81 ± 33 | 81 ± 4 | - | - | - | - | - |
| Kizhakke Puliyakote 2021 | ||||||||||||
| Nonsmokers n = 7 | 98 ± 2 | - |
L 3.5 ± 0.4c %pred 97±8 |
- | - |
L 0.80 ± 0.03c %pred 95 ± 3c |
- | - | - | - | - | - |
| Vapers n = 9 | 98 ± 1 | 99 ± 1 |
L 4.3 ± 0.9c %pred 99±8 |
- | - |
L 0.86 ± 0.04c %pred 102±5c |
- | - | - | - | - | - |
% obs % observed, % pred % predicted, CC conventional cigarette, CI confidence interval, COPD chronic obstructive pulmonary disease, EC e-cigarette, FEV1 forced expiratory volume in one second, FEV1/FVC ratio of FEV1 to forced vital capacity, L liters, SpO2 oxygen saturation, T0 baseline (all studies), T1 1 min (Coppeta), 10 min (Palamidas, both studies), 60 min (Boulay), 120 min (Staudt), T2 15 min (Coppeta).
aSignificant difference between T0 and T1.
bSignificant difference between T0 and T2.
cSignificant difference between groups at baseline.
§Nicotine concentration.