Low Doses of Aspirin in the Prevention of Preeclampsia
- Registration Number
- NCT04070573
- Lead Sponsor
- Weill Medical College of Cornell University
- Brief Summary
Preeclampsia (PE) is a morbid and potentially lethal complication of pregnancy and is more common in women with specific risk factors. Aspirin (ASA) is currently the only prophylactic therapy for preeclampsia in high-risk women to be recognized by the US Preventive Task Force and should be initiated early in the second trimester of pregnancy, before 16 weeks of gestation. However, currently there is no literature comparing various low-dose ASA formulations in the risk reduction of PE. In the United States, the currently available low-dose ASA is over the counter and is found in 81mg tablets. Therefore, when clinicians initiate therapy with low dose ASA, they may prescribe 1 or 2 tablets of 81mg aspirin per day depending on personal preference and cannot be assisted by evidence to guide their decision.This study aims to determine the incidence of preterm PE or PE with severe features in women taking either 81mg or 162mg in a randomized setting, from a single center. The investigators hypothesize that the information gained from this trial will permit a more accurate sample size calculation for a larger clinical trial powered to accept or reject our testing hypothesis. If our hypothesis is rejected and 162mg of daily ASA is not associated with a lower incidence of severe or preterm PE compared to 81mg, this may be due to lack of power to detect a smaller effect. The investigators would then evaluate the feasibility and results and determine whether a larger trial is reasonable.
- Detailed Description
Preeclampsia (PE) is a serious and potentially fatal complication of pregnancy. It is a placental disease characterized by an elevated blood pressure in the 3rd trimester with multisystem involvement (proteinuria, elevated liver enzymes, low platelet count and/or neurologic symptoms). PE can cause pulmonary edema, seizures, or stroke and is a leading cause of maternal mortality. The pregnancy outcomes are further worsened if PE develops before term. Women who have a history of PE in a prior pregnancy, diabetes, preexisting hypertension, kidney disease, multifetal gestation or autoimmune diseases are at an increased risk to develop PE in a subsequent pregnancy.
Clinical trials evaluating the benefits of low-dose aspirin (ASA) have used a wide range of doses from 60mg to 150mg orally daily with low-dose being defined as less than 325mg per day. Taking ASA (as opposed to placebo) is thought to reduce the risk of preeclampsia by 17%, without increasing the risk of major obstetric bleeding. The number needed to treat is only 19 women. ASA is currently the only prophylactic therapy for PE in high-risk women to be recognized by the US Preventive Task Force and should be initiated early in the second trimester of pregnancy, before 16 weeks of gestation.
There has also been more awareness that the efficacy of ASA in preventing preeclampsia is limited by the poor adherence of patients to this therapy. Indeed, a cross-sectional study has estimated that up to 46% of women (n=42) on ASA therapy may not be compliant to it, as determined by a validated Simplified Medication Adherence Questionnaire (SMAQ). Adherence is essential to the efficacy of ASA in preventing preterm preeclampsia. It would therefore be of interest to obtain more information about adherence to ASA in women who need this therapy.
Assessing molecular pathways in the development of PE may allow opportunity for earlier diagnosis, specific triaging of patients to closer monitoring and further development of preventative or curative treatment strategies. Samples will be biobanked for biomarker discovery in the future.
The current literature is lacking in evidence to recommend a specific daily dose of ASA. Recent meta-analyses have suggested that there may be a dose response in the protective effect of ASA for PE. As compared to 60mg per day, an ASA dose of 100mg per day was associated with a lower relative risk of PE (0.44 vs 0.57, p=0.36). A large study of 1776 women has compared a slightly higher dose of ASA (150mg per day) to placebo and found a decrease in preterm delivery (before 37 weeks) due to PE (OR 0.38, p=0.004). Meta-analyses have shown that any dose of ASA above 60mg per day is protective and should be used to prevent PE in high risk pregnancies.
To date, there has not been any studies comparing lower doses of ASA (such as 81mg, the traditional "baby aspirin" dose sold in the US) to higher "low-dose" ASA regimens (such as 162mg) in their ability to prevent preterm or severe PE in women who are at a high risk for this devastating disease.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- 400
Pregnant patients, ≥18 years old, at less than 16 weeks' gestation (as documented by ultrasound) with at least one of the following risk factors for developing PE:
- PE in a prior pregnancy
- Chronic hypertension (prior to pregnancy or before 20 weeks' gestation)
- Type 1 or 2 diabetes
- Renal disease (proteinuria ≥300mg/day or estimated GFR<90mL/min/1.73 m2)
- Multifetal gestation
- Autoimmune disease (e.g. systemic lupus erythematous, antiphospholipid syndrome)
- Patient with known intention to terminate pregnancy
- Major fetal malformation seen on ultrasound
- Contraindication to ASA therapy (including but not limited to allergy and high bleeding risk)
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description 81mg ASA acetylsalicylic acid Patients in Arm 1, will be instructed to take one tablet of 81mg aspirin per day. 162mg ASA acetylsalicylic acid Patients in Arm 2, will be instructed to take two tablets simultaneously orally once per day.
- Primary Outcome Measures
Name Time Method Incidence of Preterm (<37 Weeks) Preeclampsia 9 months for each patient (from recruitment until 6 weeks postpartum) The incidence of preterm (\<37 weeks) preeclampsia in high risk pregnant women treated with either 81 mg or 162 mg of daily aspirin during pregnancy.
Incidence of Preeclampsia With Severe Features 9 months for each patient (from recruitment until 6 weeks postpartum) The incidence of preeclampsia with severe features (American College of Obstetricians and Gynecologists 2019 definition) in high-risk pregnant women treated with either 81 mg or 162 mg of daily aspirin during pregnancy.
Composite Primary Outcome 9 months for each participant Composite of preterm preeclampsia and/or preeclampsia with severe features
- Secondary Outcome Measures
Name Time Method Aspirin Adherence 9 months for each patient (from recruitment until 6 weeks postpartum) Evaluate and compare the adherence of pregnant women to 81mg and 162mg of daily low-dose aspirin using a validated, Simplified Medication Adherence Questionnaire (SMAQ).
Maternal and Fetal Outcomes 9 months for each patient (from recruitment until 6 weeks postpartum) Compare maternal and fetal outcomes in pregnant women at a high risk for preeclampsia who are treated with either 81mg or 162mg of daily aspirin during pregnancy, including gestational hypertension, postpartum hypertension, preterm delivery \<37 weeks, fetal growth restriction (IUGR) or low birthweight (\<2000g), placental abruption, ICU admission (maternal and neonatal), and maternal/fetal mortality.
Time-to-event for Preeclampsia: Gestational Age at Onset of Preeclampsia 9 months for each patient (from recruitment until 6 weeks postpartum) Compare the time-to-event for developing preeclampsia for women treated with 81mg vs 162mg of aspirin per day. The time to event analysis will be made using the gestational age at the onset of preeclampsia as a variable
Aspirin Adherence- All Time Points Together 9 months for each patient (from recruitment until 6 weeks postpartum) To assess the adherence to low dose aspirin in pregnant women that are at high risk for preeclampsia and compare compliance rates for women on 81mg vs 162mg of aspirin per day using urine studies for salicylates and serum analysis. All time points together
Trial Locations
- Locations (2)
New York Presbyterian - Weill Cornell
🇺🇸New York, New York, United States
New York Presbyterian Queens
🇺🇸New York, New York, United States