Blood Pressure Variability and Adverse Pregnancy and Cardiovascular Outcomes in the ALSPAC Cohort

Outside pregnancy, blood pressure variability (BPV) predicts cardiovascular events. We aimed to study associations (if any) between visit-to-visit BPV in pregnancy and (1) adverse maternal/perinatal outcomes, and (2) long-term maternal cardiovascular outcomes. We conducted a secondary analysis of data from ALSPAC (Avon Longitudinal Study of Parents and Children).

Adjusted logistic regression assessed relationships between visit-to-visit BPV (by the measures of SD, average real variability, and variability independent of mean) and pregnancy outcomes (gestational/severe hypertension, preeclampsia, preterm birth, small-for-gestational-age infants, neonatal intensive care unit admission, stillbirth, and perinatal death). Adjusted Cox regression assessed relationships between visit-to-visit BPV measures and long-term maternal outcomes: hypertension (measured), diabetes (self-reported), and heart disease (self-reported) as a composite.

Among 12 509 women in ALSPAC, 4956 answered a follow-up questionnaire and 4426 attended a follow-up clinic, an average of 22 years after the index pregnancy. Measures of variability in systolic and diastolic BP (by each of SD, average real variability, and variability independent of mean) were associated with adverse pregnancy outcomes, particularly severe hypertension and preeclampsia by SD and variability independent of mean (adjusted odds ratios, 1.30-2.11). BPV in pregnancy was not associated with hypertension, diabetes, or heart disease at follow-up in adjusted analyses.

Our findings indicate that BP variation between antenatal visits is informative for identifying risk of short-term adverse pregnancy outcomes, but BPV provides no long-term utility in predicting cardiovascular risk.