(256) Activity restriction and time from diagnosis to delivery among patients with preterm pre-eclampsia

Objective: To determine the association between activity restriction and time from diagnosis to delivery among patients diagnosed with gestational hypertension (gHTN) or pre-eclampsia without severe features.

Study Design:

This is a secondary analysis of nulliparous patients enrolled in the nuMoM2b study. Individuals with gHTN or pre-eclampsia without severe features diagnosed < 37 weeks were included. Individuals with other forms of hypertensive disorders of pregnancy (HDP) were excluded because their management is more dependent on the timing of diagnosis and severity of disease. The primary outcome was days between diagnosis and delivery. The secondary outcome was development of pre-eclampsia with severe features or eclampsia. The exposure was patient report of a recommendation for activity restriction. Cox proportional hazard and logistic regression models adjusted for gestational age at diagnosis, age, diabetes, and fetal growth restriction were performed.

Results:

Of 9,289 patients, 299 (3%) were first diagnosis gHTN or pre-eclampsia without severe features prior to 37 weeks; 232 (78%) responded to the survey question about activity restriction. Of respondents, 53% reported being instructed to restrict their physical activity. There was no difference in the gestational age at diagnosis between the activity restriction vs. no restriction groups: median 33.9 (IQR 30.6, 35.9) vs. median 33.1 (IQR 29.8, 36.1), p=0.72. Activity restriction was associated with an increased risk of delivery (adjusted hazard ratio 1.42 (95%CI 1.09, 1.86)) but not with the development of more severe disease (adjusted odds ratio 1.24 (95%CI 0.70, 2.20)).

Conclusion:

Activity restriction was commonly recommended but not associated with an increased time between diagnosis and delivery or the development of severe features for individuals with gHTN or pre-eclampsia without severe features. The increased risk of delivery for activity restriction may represent confounding (e.g., severity) not captured by the initial diagnosis. Given the lack of evidence, larger studies are needed to evaluate the role for activity restriction in HDP.