Table 2.
Univariate and multivariable logistic regression to investigate the relationship of asthma diagnosis, uncontrolled asthma status during pregnancy and early pregnancy 25OHD (10–18 weeks of gestation) with preeclampsia including other potential confounders (Nsubjects=816). Bayesian Information Criterion was applied to identify the model with important variables (lowest BIC) using a step-by-step inclusion and exclusion of confounders and main variable of interests (please see supplemental Table 1 for the addtional comparative models).
| Variables | Univariate model ORa (CIb) |
Multivariable model including all variables§ (with lowest BIC) adjusted OR (CI) |
|---|---|---|
|
| ||
| Physician-diagnosed asthma | ||
| No | Ref | --------- |
| Yes | 1.15 (0.69–1.90) | |
|
| ||
| Uncontrolled asthma month per monthly visitc | 4.15 (1.2–12.53) | 3.75 (1.15–13.0) |
|
| ||
| Serum 25OHD at enrollment (10–18 weeks, ng/ml) | 0.95 (0.92–0.98)* | 0.95 (0.92–0.98)* |
|
| ||
| Age>35 (years) | ||
| No | Ref | --------- |
| Yes | 0.78 (0.23–1.99) | |
|
| ||
| Number of pregnanciesd | 0.79 (0.64–0.96) | 0.69 (0.55–0.86) |
|
| ||
| Site | ||
| Boston | Ref | |
| San Diego | 0.99 (0.48–2.0) | --------- |
| St. Louis | 2.0 (1.10–3.90) | |
|
| ||
| Trial arm | ||
| Control | Ref | |
| Vitamin D intervention | 0.97 (0.57–1.60) | --------- |
|
| ||
| Gestational diabetes | ||
| No | Ref | |
| Yes | 1.35 (0.46–3.25) | --------- |
|
| ||
| BMIe at first appointment (kg/m2) | 1.047 (1.02–1.08) | 1.04 (1.006–1.073) |
|
| ||
| Race | ||
| White | Ref | |
| African- American | 1.65 (0.95–2.94) | --------- |
| Other | 1.20 (0.53–2.57) | |
|
| ||
| Maternal marital status | ||
| Not Married/Divorced | Ref | --------- |
| Married | 0.95 (0.92–0.99) | |
|
| ||
| Education completed | ||
| college graduate/graduate school | Ref | |
| less than high school | 3.83 (1.68–8.94) | |
| high school, technical school | 2.75 (1.35–5.94) | |
| some college | 2.31 (1.07–5.20) | --------- |
|
| ||
| Annual Family Income | ||
| <$50,000 | Ref | |
| >$50,000 | 0.98 (0.94–1.02) | --------- |
| Unknown or Refused | 1.03 (0.98–1.08) | |
Odds Ratio
Confidence Interval
Total number of uncontrolled asthma months during study time until delivery/number of monthly visits during study time until delivery.
Total number of previous and current pregnancies
Body Mass index
P=0.51 By Hosmer-Lemeshow test for goodness of fit (GOF).
Values were rounded by two digits.