The Effect of Two Aspirin Dosing Strategies for Obese Women at High Risk for Preeclampsia

The Ohio State University

Status and phase: Terminated; Phase 4

Conditions: Preeclampsia

Treatments: Drug: 162mg aspirin dose

Study type: Interventional

Funder types: Other

Identifiers

NCT03735433

OBASA

Details and patient eligibility

About

Low dose aspirin (LDA) is used for preeclampsia (PE) prevention in high risk women, but the precise mechanism and optimal dose is not known. Evidence in the non-obstetric literature suggests AR may be more common among patients with a high body mass index (BMI). Recent unpublished data showed that LDA substantially lowers TxB2 levels regardless of BMI, but rates of complete platelet inhibition are lower in women with BMI ≥40. This data suggests that higher doses of ASA may be necessary in obese women. Therefore we plan determine if use of 162mg compared to the traditional 81mg ASA decreased rates of preeclampsia in women considered high risk for developing preclampsia.

Full description

Evidence suggests that an imbalance in prostacyclin and thromboxane A2 (TxA2) plays a key role in PE. Aspirin (ASA) has a dose-dependent effect blocking production of TxA2, a potent stimulator of platelet aggregation (PA) and promoter of vasoconstriction. Incomplete inhibition of PA, designated aspirin resistance (AR), can be reduced by increasing the ASA dose.

Enrollment: 152 patients

Sex: Female

Ages: 18 to 45 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• BMI at enrollment >/= 30
• plan for ASA for preeclampsia prevention

Exclusion criteria

• BMI < 30
• already on ASA

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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152 participants in 2 patient groups

81 mg daily aspirin dose

No Intervention group

Description:

obese women \>30 BMI at risk for preeclampsia will receive recommended 81mg ASA

162mg daily aspirin dose

Active Comparator group

Description:

obese women \>30 BMI at risk for preeclampsia will receive increased dose of 162mg ASA

Treatment:

Drug: 162mg aspirin dose