Table 3.
| a. Associations between urinary 1-OHPG concentrations and indoor air nicotine, PM2.5, PM2.5–10, and PM10 concentrations. | ||||
|---|---|---|---|---|
| Crudea
|
Adjustedb
|
|||
| β (95% CI) | P-value | β (95% CI) | P-value | |
| Air nicotine | ||||
| Urine collected on day 3 | 0.157 (0.061, 0.252) | 0.001 | 0.129 (0.035, 0.223) | 0.007 |
| Urine collected on day 7 | 0.007 (−0.131, 0.144) | 0.923 | −0.006 (−0.147, 0.134) | 0.928 |
| Indoor PM2.5 | ||||
| Urine collected on day 3 | 0.040 (−0.211, 0.290) | 0.757 | 0.020 (−0.257, 0.296) | 0.888 |
| Urine collected on day 7 | 0.014 (−0.215, 0.244) | 0.902 | 0.046 (−0.199, 0.292) | 0.711 |
| Indoor PM2.5–10 | ||||
| Urine collected on day 3 | 0.113 (−0.100, 0.326) | 0.297 | 0.083 (−0.127, 0.293) | 0.437 |
| Urine collected on day 7 | 0.144 (−0.003, 0.291) | 0.055 | 0.177 (0.027, 0.326) | 0.021 |
| Indoor PM10 | ||||
| Urine collected on day 3 | 0.143 (−0.165, 0.450) | 0.364 | 0.094 (−0.240, 0.429) | 0.580 |
| Urine collected on day 7 | 0.142 (−0.085, 0.370) | 0.220 | 0.104 (−0.133, 0.342) | 0.390 |
| b. Associations between time spent in the home and 1-OHPG, stratified by indoor air nicotine concentration (dichotomized at the median: 0.13 µg/m3). | |||||
|---|---|---|---|---|---|
| Low air nicotine
|
High air nicotine
|
P-interaction | |||
| β (95% CI) | P-value | β (95% CI) | P-value | ||
| Avg. time in home, all samples | −0.061 (−0.106, −0.017) | 0.007 | 0.005 (−0.039, 0.048) | 0.833 | 0.049 |
| Avg. time in home days 0–2 (urine day 3) | −0.034 (−0.083, 0.014) | 0.167 | −0.008 (−0.041, 0.026) | 0.658 | 0.357 |
| Avg. time in home days 4–6 (urine day 7) | −0.081 (−0.121, −0.041) | <0.001 | −0.024 (−0.069, 0.020) | 0.285 | 0.074 |
| By gender | |||||
| Boys | |||||
| Avg. time in home days 0–2 (urine day 3) | −0.055 (− −0.116, 0.006) | 0.078 | −0.023 (−0.061, 0.014) | 0.221 | 0.264 |
| Avg. time in home days 4–6 (urine day 7) | −0.088 (−0.149, −0.027) | 0.005 | −0.053 (−0.127, 0.021) | 0.164 | 0.623 |
| Girls | |||||
| Avg. time in home days 0–2 (urine day 3) | 0.011 (−0.056, 0.079) | 0.743 | 0.032 (−0.049, 0.113) | 0.442 | 0.478 |
| Avg. time in home days 4–6 (urine day 7) | −0.067 (−0.119, −0.016) | 0.011 | −0.024 (−0.075, 0.027) | 0.363 | 0.381 |
| c. Associations between average time spent (hours) in the home and urinary 1-OHPG, stratified by adults smoking in the home. | |||||
|---|---|---|---|---|---|
| No smoking
|
Smoking
|
P-interaction
|
|||
| β (95% CI) | P-value | β (95% CI) | P-value | ||
| Avg. time in the home, all samples | −0.013 (−0.065, 0.039) | 0.612 | −0.024 (−0.065, 0.018) | 0.261 | 0.758 |
| Avg. time in the home days 0–2 (urine day 3) | −0.033 (−0.075, 0.010) | 0.135 | −0.013 (−0.056, 0.030) | 0.566 | 0.628 |
| Avg. time in the home days 4–6 (urine day 7) | −0.092 (−0.144, −0.040) | < 0.001 | −0.001 (−0.044, 0.043) | 0.966 | 0.012 |
a
Adjusted for urinary creatinine.
b
Adjusted for urinary creatinine, gender, age, atopic status, season, and caregiver’s education. Bold value is statistically significant (P < 0.05).
Multivariable linear regression with GEE: adjusted for urinary creatinine, gender, age, atopic status, season, and caregiver’s education. Bold value is statistically significant (P < 0.05).
Adjusted for urinary creatinine, gender, age, atopic status, season, and caregiver’s education. Bold value is statistically significant (P < 0.05).