(727) Correlation between blood pressures and markers of inflammation in the maternal circulation in pregnancy

Hypertensive diagnostic criteria from the American Heart Association has been revised in non-pregnant individuals. However, in pregnancy the diagnosis of chronic hypertension, defined as blood pressure >/= 140/90 prior to pregnancy or 20 weeks gestation, has remained consistent. It is unclear if changes in blood pressure, such as in elevated and stage 1 hypertension, are associated with inflammatory markers. Therefore, we determine if levels of markers of inflammation were associated with blood pressure in a cohort of uncomplicated pregnancies and as compared to patients with gestational hypertension (gHTN).  

Study Design: Maternal blood samples were obtained in the third trimester close to delivery in a cohort of pregnant patients with uncomplicated pregnancies (n=96) or with gHTN (n=36), and plasma isolated for multiplex analysis of inflammatory mediators. In-depth review of the medical record was performed.  

Results:

Circulating levels of several mediators were significantly associated with increased blood pressure. Of interest, the pro-inflammatory chemokine MCP-1 was positively correlated with blood pressure (r=0.47, p< 0.001) whilst CXCL10 was negatively correlated (r=-0.36, p< 0.01). In addition, pro-inflammatory cytokines IL-5 and TNFa presented trending positive correlation with blood pressure (IL-5: r=0.22, p=0.072; TNFa: r=0.024, p=0.055). Surprisingly, the anti-inflammatory cytokine IL-4 was also positively correlated with blood pressure (r=0.24, p< 0.05). Of note, MCP-1 and CXCL10 were both significantly elevated in gHTN while IL-5 and TNFa were unchanged. 

Conclusion:

Our data suggest that specific inflammatory markers, including MCP-1 – responsible for monocyte recruitment, IL-5 and TNFa are correlated with increased blood pressure in a cohort of uncomplicated pregnancies. While MCP-1 was also significantly elevated in gHTN, this was not the case for the other cytokines. Further analysis will ascertain the role of pre-pregnancy body mass index in the level of these markers. In addition, a larger cohort is needed to have better understanding of the clinical significance of this work.