Antibodies to Oxidized Low-Density Lipoprotein, Cardiolipin, and Phosphatidyl Serine Fail to Predict the Risk of Preeclampsia

Non-Criteria Antiphospholipid Antibodies: Risk Factors for Endothelial Dysfunction in Women with Pre-Eclampsia

The association between unconventional antiphospholipid antibodies and pre-eclampsia in patients without thrombotic manifestations and its relationship with endothelial dysfunction after delivery has been studied poorly. We included 157 pregnant women, 122 of them having developed pre-eclampsia (56 non-severe and 66 severe). The determination of classical and unconventional, as well as pulse wave velocity and ankle-brachial index were performed at three months after delivery. The prevalence of unconventional antiphospholipid antibodies was 22.9% and 54.9% in patients included in control and pre-eclampsia groups, respectively (p = 0.001). The most frequent antiphospholipid antibody was IgM anti-phosphatidylserine/prothrombin in both cohorts. The presence of IgM anti-phosphatidylserine/prothrombin showed an association with the development of pre-eclampsia (OR = 5.4; CI 95% (2.0-14.9), p = 0.001) with an AUC of 0.744 (p < 0.001). Likewise, IgM anti-phosphatidylserine/prothrombin exhibited a positive linear correlation with pulse wave velocity values (rho = 0.830; p < 0.001) and an association with the presence of pulse wave velocity altered values (OR = 1.33; CI95% (1.10-1.59), p = 0.002). With regard to ankle braquial index values, the presence of IgM anti-phosphatidylserine/prothrombin displayed a weak negative correlation (rho = -0.466; p < 0.001) and an association with altered ankle braquial index values (OR = 1.08; CI 95% (1.04-1.13), p < 0.001). In patients who developed preeclampsia, the presence of IgM anti-phosphatidylserine/prothrombin could be associated with endothelial dysfunction, causing alteration of cardiovascular parameters.

Association of anticardiolipin antibodies with preeclampsia: a systematic review and meta-analysis

OBJECTIVE

To systematically review the evidence of the association of anticardiolipin antibodies with preeclampsia.

DATA SOURCES

PubMed and LILACS were perused up to June 2009, citations were searched using the ISI Web of Knowledge database, textbooks and reference lists were reviewed, and experts were contacted. Search terms included "antiphospholipid syndrome," "Hughes' syndrome," "anticardiolipin antibodies," "antiphospholipid antibodies," "anti-cardiolipin," "preeclampsia," and "pre-eclampsia."

METHODS OF STUDY SELECTION

Inclusion criteria were: cohorts, case-control, or controlled cross-sectional studies; healthy pregnancy as controls; no autoimmune diseases; immunoglobulin (Ig)G, IgM anticardiolipin antibody of at least 20 units by enzyme-linked immunosorbent assay, or both; and end-point preeclampsia.

TABULATION, INTEGRATION, AND RESULTS

Our search generated 68,528 entries and 64 full-text articles were reviewed. Twelve studies were included in the meta-analysis. Pooled odds ratio (OR) for association of anticardiolipin antibodies with preeclampsia was 2.86 (95% confidence interval [CI], 1.37-5.98). Pooled OR for anticardiolipin antibodies and severe preeclampsia was 11.15 (95% CI 2.66-46.75). Funnel plot showed minor asymmetry, and the Egger test was not significant (P=.359). Meta-regression identified study design and size as related to heterogeneity.

CONCLUSION

Moderate-to-high levels of anticardiolipin antibodies are associated with preeclampsia, but there is insufficient evidence to use anticardiolipin antibodies as predictors of preeclampsia in clinical practice.

A case-control study of oxidized low density lipoproteins and preeclampsia risk

Diffuse vascular endothelial dysfunction, secondary to oxidative stress, is an important pathological feature of preeclampsia. Oxidative conversion of low density lipoproteins (LDL) to oxidized-LDL (Ox-LDL) is considered an important step in transforming macrophages into lipid-laden foam cells destined to develop into early atherosclerotic-like lesions. In our study of 95 women with preeclampsia and 100 controls, we evaluated the association between maternal plasma Ox-LDL concentrations and preeclampsia risk. Ox-LDL concentrations were measured using a solid phase two-site enzyme immunoassay. Plasma lipids were measured using standard enzymatic procedures. We used logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) adjusted for confounders. Plasma Ox-LDL concentrations were positively correlated with cholesterol, triglyceride (TG), and LDL concentrations in cases and controls, (Spearman's r ranging from 0.39-0.48, p-values all <0.01). There was no evidence of an increased risk of preeclampsia across increasing quartiles of Ox-LDL. The ORs for successive quartiles, with the lowest as the reference group, were as follows: 1.0, 1.1, 0.6, and 1.2. Women with extremely high concentrations of Ox-LDL (> or =73 U/L, the upper decile), as compared with those with lower values (<73 U/L) had a 2.7-fold increased risk of preeclampsia (95% CI 1.0-6.8). Women with high Ox-LDL and high TG concentrations (> or =284 mg/dl), as compared with those without these two factors, had a 9.6-fold increased preeclampsia risk (95% CI 2.0-45.6). Elevated Ox-LDL, particularly in conjunction with elevated TG, appears to be a risk factor of preeclampsia.

Antibodies against copper-oxidised and malondialdehyde-modified low density lipoproteins in pre-eclampsia pregnancies

OBJECTIVE

To measure auto-antibodies against oxidatively modified low density lipoprotein (LDL) in pre-eclamptic pregnancies using two different techniques.

DESIGN

Clinical study comparing pre-eclamptic and normal pregnancies.

SETTING

Tampere University Hospital, Finland.

POPULATION

Twenty-one primigravidae with pre-eclampsia and 13 healthy, normotensive primigravidae as controls.

METHODS

The serum titers of antibodies against both malondialdehyde-modified and copper-oxidised LDL (MDA-LDL and copper-ox LDL) were analysed and related to parameters reflecting the severity of pre-eclampsia.

RESULTS

There was a positive correlation (r = 0.58) between antibodies against MDA-LDL and copper-ox LDL in women with pre-eclampsia but not in healthy pregnant controls. The antibody levels against copper-ox LDL, but not against MDA-LDL, were higher in women with pre-eclampsia than in women with a normal pregnancy (P < 0.01). While the antibody titers against copper-ox LDL did not correlate with any parameter reflecting the severity of pre-eclampsia, those against MDA-LDL showed a positive correlation with the level of diastolic blood pressure (r = 0.54) and a negative correlation with platelet count (r = -0.61) in women with pre-eclampsia.

CONCLUSION

There are increased titers of serum autoantibodies against copper-oxidised LDL in pre-eclampsia, which may reflect enhanced lipid peroxidation involving circulating lipoproteins.