Comparison of the associations between office and home BP with placenta-mediated pregnancy complications: the BOSHI study

This prospective cohort study compared the associations between office blood pressure (OBP) and home blood pressure (HBP) measured before 20 weeks of gestation with the subsequent development of placenta-mediated pregnancy complications (PMPCs). A total of 975 pregnant women were included in the study. OBP and HBP were measured between 10 weeks 0 days and 19 weeks 6 days of gestation, using HBP values from the same gestational weeks as OBP. When both OBP and HBP were included simultaneously in a binary logistic regression model, per 1 standard deviation increase, the adjusted odds ratios (aORs) for office and home systolic blood pressure (SBP) were 1.16 (95% confidence interval [CI]: 0.95-1.42) and 1.68 (95% CI: 1.36-2.09), respectively. For diastolic blood pressure (DBP), the aORs were 1.36 (95% CI: 1.10-1.69) for office and 1.70 (95% CI: 1.37-2.12) for home measurements. The likelihood ratio test showed that adding home SBP to a model with office SBP improved model fit (P value < 0.0001), whereas adding office SBP to a model with home SBP did not (P value = 0.2). For DBP, adding either home or office values improved model fit (P value < 0.0001 and P value = 0.005, respectively). Home SBP was more strongly associated with PMPCs than office SBP. Although home DBP was not statistically stronger than office DBP, its effect estimate was higher. These findings support the added value of HBP monitoring during pregnancy for predicting PMPCs.