Journal of Hypertension: Open Access

Objectives: Women with hypertensive disorders of pregnancy (HDP), including both preeclampsia (PE) and gestational hypertension (GH), show fluctuations in BP during the day. This study aimed to assess characteristic changes in BP by Ambulatory blood pressure (BP) monitoring (ABPM) in HDP patients in comparison with PE and GH.
Study design: Among the 106 pregnant women who exhibited hypertension by clinic BP (CBP), 24-hour ABPM were performed. ABPM determined HDP in 79 women (PE, n=43) and GH, n=36), and white coat hypertension (WCH) in 27 women.
Main outcome measures: The following aspects were analyzed with the circadian rhythms of BP and pulse: 1) changes in BP at night-time and 2) multiple regression percent rhythm (PR, correction coefficient by Cosinor analysis).
Results: Mean BP by 24-hour ABPM was higher in women with PE and GH compared to those with WCH. In systolic BP (SBP), most women with PE and GH were riser or non-dipper. Half of the women with PE and GH experienced a loss of circadian rhythm of SBP (PR<0.16). In women with circadian rhythm (PR ≥0.16), normal maximal SBP at daytime (acrophase time from 12:00 to 18:00) was observed in only 9 of 43 women with PE and 9 of 36 women with GH. Furthermore, PR of pulse was lower in women with PE, but not in those with GH or WCH.
Conclusions: Our findings suggest that the circadian rhythm of BP in women with PE may be abnormal due to possibly sympathetic nerve disorders.