Non-Criteria Obstetric Antiphospholipid Syndrome: How Different Is from Sidney Criteria? A Single-Center Study

Abstract

This study aims to compare the demographic characteristics, clinical features, serology, and fetal-maternal outcomes between women with obstetric antiphospholipid syndrome (APS) and those with non-criteria (NC)-APS and seronegative (SN)-APS. Two-hundred and sixty-three women with APS obstetric morbidity ever pregnant were included. Of those, 66 met the APS classification criteria, 140 were NC-APS, and 57 were SN-APS. Patients with other autoimmune diseases were excluded. Adverse pregnancy outcomes (APO) included early pregnancy loss, fetal death, preeclampsia, abruptio placentae, and preterm birth. The mean age of the study group was 33.6 ± 5.3 years, and patients were followed up for 129.5 ± 81.9 months. In the NC-APS group, 31 (22.1%) did not fulfill clinical and serological criteria (Subgroup A), 49 (35%) did meet clinical but not serologic criteria (Subgroup B), and 60 (42.9%) fulfilled the serologic criteria but not the clinical ones (Subgroup C). The cardiovascular risk burden was higher in the APS group, due to a higher proportion of smoking. Patients with criteria APS received more intensive treatment than patients in the other study groups. The addition of standard of care (SoC) treatment significantly improved live birth and decreased APO in all groups. Significant clinical differences were observed between the study groups. However, when treated with SoC, fetal-maternal outcomes were similar, with a significant improvement in live births and a decrease in APO. Risk stratification in patients with obstetric morbidity associated with APS can help individualize their treatment.

Keywords: antiphospholipid antibodies; antiphospholipid syndrome; fetal loss; non-criteria; obstetric morbidity; pregnancy.

Figure 1

Pregnancy loss in the different groups according to treatment. Rates of patients with pregnancy loss (early pregnancy loss (<10 weeks) and/or fetal death (>10 weeks)) are expressed as percentages in the different groups according to standard (SoC) treatment. * Criteria APS vs. NC-APS: p = 0.023; ^§ Criteria APS vs. SN-APS: p < 0.05.

Figure 2

Adverse Pregnancy Outcomes (APO) in the different groups according to treatment. Rates of patients with APO are expressed as percentages in the different groups according to standard (SoC) treatment. Adverse pregnancy outcome (APO) includes early pregnancy loss, fetal death, preeclampsia, abruptio placentae, and preterm birth (< 37 weeks). * Criteria APS vs. NC-APS: p < 0.0001; ^§ Criteria APS vs. SN-APS: p < 0.05.

Figure 3

Proportion of successful pregnancy in the study groups after standard treatment. The results show the percentage of live births compared to the number of patients with or without standard (SoC) treatment.