Table 1. Characteristics of the study participants according to electronic cigarette exposure (N = 14,738).
| Never users (n = 13,459) | Ever users (n = 954) | Current users (n = 325) | P-value | |
|---|---|---|---|---|
| Age (years) | 47.6 (0.2) | 36.5 (0.4) | 35.8 (0.6) | <0.001*,† |
| Male | 51.1% (0.5) | 89.9% (1.0) | 88.2% (1.8) | <0.001*,† |
| Smoking status | <0.001*,† | |||
| Never | 60.8% (0.5) | 2.3% (0.5) | 2.2% (0.8) | |
| Former | 20.2% (0.4) | 18.8% (1.5) | 12.7% (2.0) | |
| Current | 19.0% (0.5) | 78.9% (1.6) | 85.0% (2.2) | |
| High-risk alcohol consumptiona) | <0.001*,† | |||
| ≥1/week | 52.9% (0.6) | 54.9% (1.8) | 56.2% (3.0) | |
| <1/week | 47.1% (0.6) | 45.1% (1.8) | 43.8% (3.0) | |
| Physical activityb) | 0.33 | |||
| Yes | 52.9% (0.6) | 54.9% (1.8) | 56.2% (3.0) | |
| No | 47.1% (0.6) | 45.1% (1.8) | 43.8% (3.0) | |
| Household income | <0.01*,† | |||
| Lowest | 11.8% (0.5) | 8.7% (1.0) | 7.3% (1.6) | |
| Lower middle | 22.9% (0.6) | 22.2% (1.5) | 20.1% (2.5) | |
| Higher middle | 30.9% (0.7) | 35.4% (1.8) | 39.2% (3.4) | |
| Highest | 34.4% (0.9) | 33.7% (1.7) | 33.4% (3.2) | |
| Educational level | <0.001*,† | |||
| Middle school or lower | 18.0% (0.5) | 5.9% (0.8) | 4.5% (1.1) | |
| High school | 27.9% (0.6) | 28.2% (1.6) | 31.1% (2.8) | |
| College or more | 54.1% (0.8) | 65.9% (1.7) | 64.4% (2.9) | |
| Body mass index | <0.001*,† | |||
| <18.5 kg/m2 | 4.3% (0.2) | 4.1% (0.8) | 5.4% (1.6) | |
| 18.5–22.9 kg/m2 | 40.6% (0.5) | 29.9% (1.6) | 29.9% (2.7) | |
| 23.0–24.9 kg/m2 | 22.9% (0.4) | 23.7% (1.5) | 19.0% (2.3) | |
| 25.0≥ kg/m2 | 32.2% (0.5) | 42.2% (1.9) | 45.8% (3.2) | |
| Metabolic variables | ||||
| WC (cm) | ||||
| Men | 85.5 (0.1) | 86.1 (0.4) | 87.4 (0.7) | 0.01† |
| Women | 77.2 (0.2) | 74.8 (0.9) | 76.0 (1.7) | 0.03* |
| Triglyceride (mg/dL) | 136.4 (1.5) | 173.1 (4.5) | 185.3 (10.4) | <0.001*,† |
| Fasting glucose (mg/dL) | 98.7 (0.2) | 97.6 (0.8) | 98.4 (1.2) | 0.41 |
| HDL-cholesterol (mg/dL) | ||||
| Men | 48.2 (0.2) | 47.5 (0.5) | 47.1 (0.7) | 0.14 |
| Women | 56.3 (0.2) | 59.3 (1.4) | 59.3 (1.8) | 0.03 |
| SBP (mmHg) | 116.3 (0.2) | 116.7 (0.5) | 115.8 (0.7) | 0.55 |
| DBP (mmHg) | 75.7 (0.1) | 77.6 (0.4) | 77.5 (0.6) | <0.001*,† |
Data are presented as weighted percentages (standard errors [SEs]) for categorical variables or weighted means (SEs) for continuous variables, unless otherwise stated.
P-values were calculated using a one-way analysis of variance for continuous variables and chi-square test for categorical variables.
Post-hoc analyses with Bonferroni’s correction were performed between *never vs. ever, †never vs. current, and ‡ever vs. current e-cig users. A P-value <0.017 was considered significant.
a) Heavy alcohol consumption was defined as the consumption of ≥7 drinks in men and ≥5 drinks in women on an occasion.
b) Adequate physical activity was defined as 1) at least 150–300 minutes of moderate-intensity physical activity per week, 2) 75–150 minutes of vigorous-intensity physical activity per week, or 3) an equivalent combination of moderate- and vigorous-intensity aerobic activities.
WC: waist circumference, HDL: high-density lipoprotein, SBP: systolic blood pressure, DBP: diastolic blood pressure.