Table 3.
Coefficients From Multivariable Linear Regression for Primary Outcome of Feno Levels and Secondary Outcomes of Blood Eosinophil and C-Reactive Protein Levels
| Variable | ln(Feno) |
Blood Eosinophil Level |
CRP Levela |
|||
|---|---|---|---|---|---|---|
| Regression Coefficient (95% CI) (n = 12,059) |
P Value | Regression Coefficient (95% CI) (n = 11,795) |
P Value | Regression Coefficient (95% CI) (n = 8,115) |
P Value | |
| Age group 1b | Referent | Referent | Referent | |||
| Age group 2b | 0.15 (0.11-0.18) | < .001 | 0.01 (0.00-0.02) | .032 | 0.04 (0.01-0.08) | .013 |
| Height (per 10 cm of height) | 0.05 (0.03-0.07) | < .001 | −0.01 (−0.01 to 0.00) | .002 | 0.00 (−0.03 to 0.03) | .801 |
| BMI | ||||||
| Normal | Referent | Referent | Referent | |||
| Underweight | −0.01 (−0.15 to 0.13) | .917 | 0.01 (−0.03 to 0.05) | .645 | −0.14 (−0.20 to −0.08) | < .001 |
| Overweight | 0.02 (−0.02 to 0.05) | .264 | 0.02 (0.01-0.03) | < .001 | 0.07 (0.02-0.12) | .006 |
| Obese | ||||||
| Class I | 0.02 (−0.03 to 0.06) | .409 | 0.02 (0.01-0.03) | < .001 | 0.19 (0.14-0.24) | < .001 |
| Class II | 0.00 (−0.06 to 0.05) | .847 | 0.03 (0.02-0.05) | < .001 | 0.40 (0.31-0.50) | < .001 |
| Class III | 0.00 (−0.08 to 0.09) | .902 | 0.06 (0.04-0.07) | < .001 | 0.68 (0.55-0.80) | < .001 |
| Sex | ||||||
| Male | Referent | Referent | Referent | |||
| Female | −0.17 (−0.21 to −0.13) | < .001 | −0.04 (−0.05 to −0.03) | < .001 | 0.08 (0.04-0.12) | < .001 |
| Race | ||||||
| Non-Hispanic white | Referent | Referent | Referent | |||
| Non-Hispanic black | 0.01 (−0.03 to 0.06) | .573 | −0.02 (−0.03 to −0.01) | < .001 | 0.05 (0.01-0.10) | .018 |
| Hispanic | 0.14 (0.10-0.18) | < .001 | 0.01 (−0.01 to 0.02) | .372 | 0.03 (−0.02 to 0.08) | .224 |
| Other race/ethnicity | 0.14 (0.08-0.19) | < .001 | 0.02 (0.01-0.04) | .006 | −0.05 (−0.12 to 0.01) | .083 |
| Asthma | ||||||
| No | Referent | Referent | Referent | |||
| Yes | 0.19 (0.13-0.26) | < .001 | 0.03 (0.02-0.04) | < .001 | 0.00 (−0.07 to 0.07) | .933 |
| Average cigarettes/d | ||||||
| 0 | Referent | Referent | Referent | |||
| 1-10 | −0.46 (−0.51 to −0.41) | < .001 | 0.03 (0.02-0.05) | < .001 | 0.09 (0.01-0.18) | .034 |
| 11-20 | −0.66 (−0.74 to −0.57) | < .001 | 0.04 (0.02-0.05) | .003 | 0.12 (0.04-0.21) | .006 |
| > 20 | −0.78 (−0.87 to −0.68) | < .001 | 0.04 (0.01-0.06) | .002 | 0.24 (0.06-0.42) | .008 |
| Education | ||||||
| 12 y | Referent | Referent | Referent | |||
| ≤ 12 y | −0.02 (−0.06 to 0.01) | .238 | 0.01 (0.00-0.03) | .013 | −0.01 (−0.07 to 0.04) | .665 |
| > 12 y | 0.04 (0.01-0.08) | .018 | 0.00 (−0.01 to 0.01) | .901 | −0.03 (−0.08 to 0.03) | .313 |
| Poverty income ratio < 1 | ||||||
| No | Referent | Referent | Referent | |||
| Yes | −0.03 (−0.07 to 0.01) | .114 | 0.01 (0.00-0.02) | .099 | 0.02 (−0.02 to 0.06) | .290 |
| Inhaled steroid use | ||||||
| No | Referent | Referent | Referent | |||
| Yes | 0.02 (−0.09 to 0.13) | .673 | 0.05 (0.02-0.09) | .006 | 0.10 (−0.05 to 0.25) | .178 |
| Ate NO-rich vegetables in past 3 h | ||||||
| No | Referent | Referent | Referent | |||
| Yes | 0.10 (0.03-0.18) | < .001 | −0.01 (−0.03 to 0.00) | .155 | −0.06 (−0.13 to 0.00) | .063 |
| Hay fever | ||||||
| No | Referent | Referent | Referent | |||
| Yes | 0.15 (0.11-0.18) | < .001 | 0.02 (0.01-0.03) | < .001 | 0.02 (−0.02 to 0.07) | .298 |
| Alcohol-related liver disease | ||||||
| No | Referent | Referent | Referent | |||
| Yes | −0.02 (−0.10 to 0.06) | .625 | 0.00 (−0.01 to 0.01) | .929 | 0.05 (−0.13 to 0.22) | .610 |
| Alcohol category | ||||||
| Never drinker | Referent | Referent | Referent | |||
| Nonexcessive | −0.03 (−0.08 to 0.02) | .264 | 0.01 (0.00-0.02) | .019 | −0.06 (−0.13 to 0.02) | .136 |
| Excessive | −0.11 (−0.17 to −0.06) | < .001 | 0.01 (0.00-0.02) | .281 | −0.05 (−0.13 to 0.04) | .267 |
| Former excessive | −0.09 (−0.21 to 0.03) | .141 | −0.01 (−0.04 to 0.01) | .260 | −0.02 (−0.12 to 0.07) | .605 |
Coefficients are expressed as change in ln(Feno) per 1-unit change in the independent variable. Blood eosinophil level is expressed as cells/mm3; CRP level is expressed as ng/mL. See Table 1 legend for expansion of abbreviations.
a
Data available from 2007 to 2010.
b
Age group 1: women, 21 to 45 years and men, 21 to 59 years; age group 2: women, 46 to 79 years and men, 60 to 79 years.