Table 2.
Systolic Blood Pressure Trajectory over Pregnancy Hierarchical mixed model linear regression
| 1. Time Only (n=169) | 2. Time and PSS (n=163) | 3. Time and PSS and GA at Birth (n=139) | 4. Time and PSS and Birth Weight Percentile (n=138) | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 95% CI | 95% CI | 95% CI | 95% CI | |||||||||||||||||
| Parameter | Estimate (β) | Sth Error | p- Value | Lower Bound | Upper Bound | Estimate (β) | Sth Error | p- Value | Lower Bound | Upper Bound | Estimate (β) | Sth Error | p- Value | Lower Bound | Upper Bound | Estimate (β) | Sth Error | p- Value | Lower Bound | Upper Bound |
| Intercept | 117.76 | 0.73 | < .001 | 116.33 | 119.19 | 117.69 | 0.75 | < .001 | 116.22 | 119.16 | 117.24 | 0.83 | < .001 | 115.60 | 118.88 | 117.28 | 0.82 | < .001 | 115.67 | 118.89 |
| Posture – lying down | −4.62 | 0.34 | < .001 | −5.29 | −3.95 | −4.67 | 0.35 | < .001 | −5.35 | −3.98 | −4.64 | 0.37 | < .001 | −5.38 | −3.91 | −4.70 | 0.38 | < .001 | −5.44 | −3.96 |
| Posture – standing | 3.33 | 0.49 | < .001 | 2.36 | 4.30 | 3.31 | 0.50 | < .001 | 2.32 | 4.29 | 3.40 | 0.54 | < .001 | 2.33 | 4.46 | 3.29 | 0.55 | < .001 | 2.20 | 4.37 |
| Posture – walking | 4.66 | 0.45 | < .001 | 3.78 | 5.53 | 4.60 | 0.45 | < .001 | 3.71 | 5.48 | 5.11 | 0.49 | < .001 | 4.16 | 6.06 | 5.06 | 0.49 | < .001 | 4.10 | 6.02 |
| Posture – sitting (reference category) | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | ||||||||||||||
| Pre-pregnancy body mass index | 0.25 | 0.08 | 0.002 | 0.09 | 0.41 | 0.25 | 0.08 | 0.004 | 0.08 | 0.41 | 0.26 | 0.08 | 0.003 | 0.09 | 0.43 | 0.27 | 0.09 | 0.003 | 0.10 | 0.45 |
| GA | −0.03 | 0.10 | 0.774 | −0.22 | 0.16 | −0.01 | 0.10 | 0.953 | −0.20 | 0.19 | −0.05 | 0.11 | 0.667 | −0.26 | 0.17 | −0.05 | 0.11 | 0.630 | −0.26 | 0.16 |
| GA2 | 0.01 | 0.00 | 0.010 | 0.00 | 0.02 | 0.01 | 0.00 | 0.018 | 0.00 | 0.02 | 0.01 | 0.00 | 0.006 | 0.00 | 0.02 | 0.01 | 0.00 | 0.007 | 0.00 | 0.02 |
| PSS | −0.13 | 0.11 | 0.216 | −0.34 | 0.08 | −0.10 | 0.12 | 0.387 | −0.34 | 0.13 | −0.01 | 0.12 | 0.938 | −0.25 | 0.23 | |||||
| GA x PSS | 0.03 | 0.02 | 0.072 | 0.00 | 0.06 | 0.02 | 0.02 | 0.193 | −0.01 | 0.06 | 0.01 | 0.02 | 0.763 | −0.03 | 0.04 | |||||
| GA2 x PSS | 0.00 | 0.00 | 0.151 | 0.00 | 0.00 | 0.00 | 0.00 | 0.302 | 0.00 | 0.00 | 0.00 | 0.00 | 0.909 | 0.00 | 0.00 | |||||
| GA at birth | 0.07 | 0.78 | 0.929 | −1.47 | 1.61 | |||||||||||||||
| GA x GA at birth | 0.21 | 0.10 | 0.047 | 0.00 | 0.41 | |||||||||||||||
| GA2 x GA at birth | −0.01 | 0.00 | 0.013 | −0.02 | 0.00 | |||||||||||||||
| GA at birth x PSS | 0.15 | 0.13 | 0.251 | −0.10 | 0.39 | |||||||||||||||
| GA x GA at birth x PSS | −0.01 | 0.02 | 0.745 | −0.04 | 0.03 | |||||||||||||||
| GA2 x GA at birth x PSS | 0.00 | 0.00 | 0.934 | 0.00 | 0.00 | |||||||||||||||
| Birth weight percentile | −0.11 | 0.03 | 0.001 | −0.18 | −0.04 | |||||||||||||||
| GA Birth weight percentile | 0.02 | 0.00 | < .001 | 0.01 | 0.03 | |||||||||||||||
| GA2 x Birth weight percentile | 0.00 | 0.00 | < .001 | 0.00 | 0.00 | |||||||||||||||
| Birth weight percentile x PSS | −0.01 | 0.01 | 0.179 | −0.02 | 0.00 | |||||||||||||||
| GA x Birth weight percentile x PSS | 0.00 | 0.00 | 0.244 | 0.00 | 0.00 | |||||||||||||||
| GA2 x Birth weight percentile x PSS | 0.00 | 0.00 | 0.279 | 0.00 | 0.00 | |||||||||||||||
Bold indicates significant effects.
All variables were centered.
Sample size increased due to removal of birth outcomes from the model.
CI= confidence interval; GA = gestational age in weeks
PSS = Perceived Stress Scale; Std Error = standard error of the mean