(401) Is BMI responsible for variation in hsCRP with Aspirin exposure?

To determine if high sensitivity C-reactive protein (hsCRP) serum concentrations changed significantly between the first and third trimesters in subpopulations exposed to different doses of aspirin (LDA) prophylaxis stratified by BMI.

Study Design:

This is a secondary analysis from an open-label randomized control study of 81 vs 162 mg LDA prophylaxis with patients enrolled based on USPSTF major criteria (pooled cohort of all aspirin-exposed defined as the high-risk group). A third convenience, low-risk control population was also simultaneously recruited. Serum samples were obtained prior to aspirin initiation and at 28-32 weeks’ gestation. Analysis included groupings based on LDA exposure to any dose vs controls; and also based on specific dose, 0 vs 81 mg vs 162 mg. hsCRP levels were analyzed using an enzyme immunoassay test kit (BioCheck, Inc, Foster City, CA; Cat # BC-1119) utilizing quantitative sandwich enzyme immunoassay technique (ELISA). Statistical analysis included oneway ANOVA and pooled T-test.

Results:

171 subjects were grouped based on LDA exposure:  81mg (n= 69), 162mg (n= 75), and no LDA / control (“low risk”, n= 65). Serial first and third hsCRP results were available for 129 patients (76%). Groups were similar with regard to age and race; see Table 1. Women in the high-risk group were more likely to be obese (p=0.0003). Women who received 162mg LDA were more likely to report tobacco use (p=0.0037). At baseline a significant difference in hsCRP was not identified between 3 subgroups stratified by aspirin exposure (p=0.09); however, in the third trimester, this biomarker did differ significantly between these groups (p=0.048). No difference in hsCRP concentrations in the third trimester or change in hsCRP from baseline to third trimester was evident in subgroups stratified by BMI; see Table 2.

Conclusion:

Although variation in hsCRP was evident in third trimester between high-risk aspirin exposed subgroups and low-risk patients, BMI was not clearly associated as an explanatory variable for this difference suggesting a potential mechanism for LDA on inflammation.