Characteristics of adults 18–39 years at wave 2 of the PATH Study*, by lifetime asthma status (percentages and means are weighted to reflect US population)
| Total (N=10 267) | Doctor ever said you have asthma? | P value§ | ||||
| No (N=8835) | Yes (N=1432) | |||||
| Asthma medication in P12M?† | ||||||
| No (N=1144) | Yes (N=288) | |||||
| N‡ | % or mean | % | % | % | ||
| Past 30-day tobacco use | ||||||
| Combustible versus non-combustible tobacco use | 0.41 | |||||
| Never used tobacco | 2010 | 30.5 | 30.9 | 28.6 | 26.0 | |
| Formerly used tobacco | 3231 | 34.0 | 33.7 | 35.2 | 39.3 | |
| Non-combustible use only | 392 | 3.1 | 3.1 | 2.7 | 4.7 | |
| Any combustible use | 4634 | 32.4 | 32.3 | 33.4 | 29.9 | |
| Specific tobacco products used | ||||||
| Cigarette | 3708 | 25.9 | 25.9 | 26.7 | 21.5 | 0.27 |
| Cigar | 1645 | 10.8 | 10.5 | 13.4 | 10.5 | 0.03 |
| Hookah | 984 | 6.2 | 6.1 | 6.7 | 7.5 | 0.44 |
| E-cigarette | 1323 | 9.1 | 9.1 | 9.6 | 9.0 | 0.83 |
| Smokeless | 576 | 4.3 | 4.3 | 4.6 | 3.6¶ | 0.77 |
| Other smoke-related exposures | ||||||
| Cigarette pack-years (mean) | 10 267 | 2.0 | 2.1 | 1.9 | 1.7 | 0.41 |
| Past-week hours of SHS exposure (mean) | 10 267 | 5.4 | 5.4 | 5.8 | 5.8 | 0.32 |
| Past-month marijuana use** | 2225 | 15.2 | 14.7 | 19.1 | 17.2 | <0.01 |
| Relevant medical history | ||||||
| Body mass index | <0.01 | |||||
| Underweight | 336 | 2.8 | 2.9 | 2.3 | 3.3¶ | |
| Normal | 4292 | 40.3 | 40.9 | 38.7 | 27.0 | |
| Overweight | 2906 | 30.3 | 30.3 | 29.3 | 33.3 | |
| Class 1 obese | 1521 | 14.6 | 14.5 | 14.9 | 15.0 | |
| Class 2+ obese | 1212 | 12.0 | 11.4 | 14.8 | 21.5 | |
| Asthma Control Test (mean score) | 1420 | 23.1 | N/A | 23.7 | 20.6 | <0.01 |
| Sociodemographics | ||||||
| Age | <0.01 | |||||
| 18–24 | 5292 | 34.1 | 33.2 | 41.6 | 35.0 | |
| 25–39 | 4975 | 65.9 | 66.8 | 58.4 | 65.0 | |
| Sex | <0.01 | |||||
| Female | 5341 | 50.4 | 50.0 | 50.3 | 63.2 | |
| Male | 4926 | 49.6 | 50.0 | 49.7 | 36.8 | |
| Race/ethnicity | 0.01 | |||||
| White†† | 5569 | 58.3 | 57.9 | 61.3 | 62.1 | |
| Black†† | 1512 | 11.9 | 11.7 | 13.7 | 13.5 | |
| Other†† | 884 | 9.8 | 9.9 | 9.5 | 5.8 | |
| Hispanic | 2302 | 19.9 | 20.5 | 15.5 | 18.7 | |
| Education | 0.71 | |||||
| No high school degree | 1158 | 8.2 | 8.4 | 7.3 | 6.9 | |
| GED | 573 | 4.6 | 4.7 | 3.9 | 4.1¶ | |
| High school grad | 2484 | 21.6 | 21.7 | 20.6 | 19.9 | |
| Some college | 3950 | 36.2 | 35.8 | 38.9 | 39.6 | |
| ≥College graduate | 2102 | 29.4 | 29.4 | 29.4 | 29.5 | |
| Live in an urban area‡‡ | 8499 | 84.0 | 83.8 | 84.0 | 91.3 | 0.07 |
Online supplemental table 8 reports SEs for all the weighted estimates presented in this table and unweighted Ns for all the variables in the model.
*N=10 267 wave 2 adult (age 18–39) respondents without COPD or other non-asthma respiratory diseases at waves 2–4, with wave 4 PATH Study longitudinal (all waves) weights, and complete data on all analytical variables of adult tobacco users. A total of 1408 participants were excluded for missing data on one or more variables in the analysis. Young adults aged 18–24 years, and black participants (or African-Americans) were oversampled relative to population proportions. The weighting procedures adjusted for oversampling and non-response.
†Any P12M asthma meds based on an answer of ‘quick-relief inhaler’ or ‘controller or long-acting inhaler including steroid inhaler’ to the question ‘In the past 12 months, which of the following medications did you regularly take for COPD or asthma?’.
‡Unweighted.
§Χ2 test was used for categorical variables and ANOVA was used for continuous variables. Bold p values are statistically significant at p<0.05.
¶Estimate should be interpreted with caution because it has low statistical precision. It is based on a denominator sample size of less than 50, or the coefficient of variation of the estimate or its complement is larger than 30%.
**Marijuana use variable does not distinguish between combustible and non-combustible use.
††Non-Hispanic.
‡‡Derived at wave 1 of the PATH Study.
ANOVA, analysis of variance; COPD, chronic obstructive pulmonary disease; GED, General Education Development (high school equivalency certificate); PATH, Population Assessment of Tobacco and Health; P12M, past 12-month; SHS, secondhand smoke.