Background: Women with a history of preterm delivery have about twice the normal risk of cardiovascular disease (CVD). Mechanisms underlying this association are not well understood. The aim of the present study was to evaluate the relationships between selected metabolic CVD risk factors and markers of both systemic inflammation and endothelial dysfunction in women with spontaneous preterm labor (sPL).
Methods: This was a case-control study in a university tertiary referral center. Forty pregnant women with sPL were compared to 50 controls during gestation. Maternal serum triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, glycemia, insulinemia, homeostasis model assessment (HOMA), leptin, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), soluble vascular cell adhesion molecule (sVCAM), soluble intercellular adhesion molecule (sICAM), selectin, and myeloperoxidase (MPO) were measured.
Results: Gestational age at study was similar in both groups (31.56±3.14 weeks of gestation vs. 31.27±2.14 weeks of gestation, p=0.62, for the control and the sPL groups, respectively). Body mass index (BMI) (21.72±2.99 vs. 23.56±3.80, p=0.01), all cholesterol fractions (HDL-C 53.44±18.22 vs. 68.32±18.38, p=0.0003; LDL-C 125.71±35.56 vs. 142.15±36.07, p=0.03, and total cholesterol 219.55±32.29 vs. 240.38±40.01, p=0.009) and MPO (3.07±0.63 vs. 3.48±0.32, p=0.0009) were significantly lower in women with sPL. Serum levels of IL-6 (0.61±0.46 vs. 0.33±0.46, p=0.007) and the ratio of total cholesterol/HDL-C (4.52±1.48 vs. 3.77±1.37, p=0.01) were significantly increased and correlated each other (r=0.21, p=0.04). Logistic regression showed that the best predictive model for sPL (R(2)=0.36, p=0.001) included BMI and total cholesterol.
Conclusions: A combination of low maternal BMI, low cholesterol levels, and high total cholesterol/HDL-C ratio is present in women with sPL and is related to inflammation.