No abstract

Low-dose aspirin (LDA) is suspected to prevent development of pre-eclampsia (PE) in at-risk patients, including pregestational diabetics, through inhibition of thromboxane (TX). In non-obstetric literature, aspirin resistance (AR), or incomplete inhibition of TX production despite adequate dosing, has been linked to poor glycemic control (GC). We sought to investigate the association of poor GC on platelet-derived TX inhibition in pre-gestational diabetic women treated with LDA for PE prevention. STUDY DESIGN: This was a secondary analysis of a prospective multicentered study investigating the effect of LDA (60-mg) compared to placebo administration in pre-gestational women at high-risk for developing PE. Maternal serum TX B 2 (ng/mL) and glycosylated hemoglobin (mg/ml) levels were drawn at 3 time points: randomization (13-26 weeks), second trimester (at least 2 weeks after randomization and 24-28 weeks), and third trimester (34-38 weeks). Patients were included in the analysis if sample was collected at randomization and at least 1 time point thereafter. Median glycosylated hemoglobin and TX B 2 levels were calculated at each time point, as well as rates of complete TX B 2 inhibition (< 0.01 ng/mL). RESULTS: A total of 87 patients were included in the analysis (placebo n¼25, LDA n¼62). In placebo group there was a significant increase in glycosylated hemoglobin (p¼0.004) and no difference in TX B2 levels (p¼ 0.834). In the LDA group, there was no difference in glycosylated hemoglobin (p¼0.765), but a significant decrease in TX B2 levels among pre-gestational women receiving LDA (p < 0.001). Higher levels of glycosylated hemoglobin had the lowest odds of undetectable TX B2 levels in the at both time points (OR, 0.10; 95% CI, 0.08-0.30). CONCLUSION: High-risk women with increased glycosylated hemoglobin receiving LDA for PE prevention have higher levels of TX B 2. These data suggest that an increase in aspirin dosing may be necessary in this population.