Table 2.
Risk ratios (RR) and 95% confidence intervals (CI) for preterm birth associated with maternal race, education level, individual allostatic load biomarkers, and quartile of allostatic load index scorea
| Model 1: n = 1,456
|
Model 2: n = 1,411
|
Model 3: n = 1,263
|
Model 4: n = 375
|
Model 5: n = 375
|
Model 6: n = 375
|
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| RR | [95% CI] | RR | [95% CI] | RR | [95% CI] | RR | [95% CI] | RR | [95% CI] | RR | [95% CI] | |
| Race | ||||||||||||
| White | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] |
| African American | 1. 5 | 1.1, 2.0 | 1.6 | 1.1, 2.3 | 1.5 | 1.1, 2.3 | 1.5 | 0.8, 2.9 | 1.5 | 0.7, 2.9 | 1.4 | 0.7, 2. 6 |
| Education | ||||||||||||
| More than HS | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] |
| HS | 0.8 | 0.6, 1.3 | 0.9 | 0.6, 1.3 | 1.4 | 0.8, 2. 5 | 1.2 | 0.4, 3.5 | 1.1 | 0.5, 2.7 | 1.0 | 0.4, 2.5 |
| Less than HS | 1.4 | 0.8, 2.2 | 1.4 | 0.8, 2.3 | 1.0 | 0.7, 1.6 | 1.1 | 0.5, 2.7 | 1.3 | 0.4, 3.7 | 1.4 | 0.5, 3.5 |
| Allostatic load biomarkers | ||||||||||||
| SBP (per 10 unit increase) | 0.9 | 0.7, 1.1 | 1.0 | 0.8, 1.3 | 1.0 | 0.8, 1.2 | 0.7 | 0.5, 1.2 | 0.8 | 0.5, 1.4 | ||
| DBP (per 10 unit increase) | 1.3 | 1.1, 1.6 | 1.3 | 1.0, 1.6 | 1.4 | 1.1, 1.7 | 1.6 | 1.1, 2.5 | 1.8 | 1.1, 2.8* | ||
| BMI | 1.0 | 0.95, 1.02 | 0.99 | 0.95, 1.0 | 1.0 | 0.9, 1.1 | 1.0 | 0.9, 1.1 | ||||
| Total Cholesterol (per 10 unit increase) | 1.0 | 0.95, 1.1 | 1.0 | 0.9, 1.1 | 1.1 | 1.0, 1.3 | 1.2 | 1.0, 1.3 | ||||
| Triglyceridesb | 1.3 | 0.9, 1. 9 | 1.2 | 0.8, 1.9 | 1.3 | 0.7, 2.5 | 1.5 | 0.8, 2.8 | ||||
| Glucoseb | 0.7 | 0.1, 4.9 | 0.1 | 0.01, 0.8 | 0.1 | 0.01, 1.2 | ||||||
| Insulinb | 1.0 | 0.7, 1.5 | 1.4 | 0.9, 2.3 | 1.4 | 0.9, 2.4 | ||||||
| White blood cellsb | 4.2 | 1.3, 13.4 | 3. 9 | 1.2, 12.6 | ||||||||
| Fibrinogenb | 0.8 | 0.4, 1.4 | 0.8 | 0.4, 1.6 | ||||||||
| Allostatic load index | ||||||||||||
| Quartile 1 (lowest) | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] | 1.0 | [Reference] |
| Quartile 2 | 0.8 | 0.4, 2.4 | 0.9 | 0.4, 2.2 | ||||||||
| Quartile 3 | 0.3 | 0.1, 1.1 | 0.4 | 0.1, 1.4 | ||||||||
| Quartile 4 (highest) | 0.5 | 0.1, 2.6 | 1.2 | 0.5, 2.8 | ||||||||
a
All models adjusted for maternal age at first birth, smoking during pregnancy, date of BHS examination, and years between allostatic load. measurement and conception.
b
Biomarkers that deviated from normality were log (basee) transformed before entered in the model.
BMI, body mass index; BHS, Bogalusa Heart Study; DBP, diastolic blood pressure; HS, high school; RR, risk ratio; SBP, systolic blood pressure.