Thrombotic risk assessment in antiphospholipid syndrome: do noncriteria antibodies contribute?

Background/aim

In this cross-sectional study, it was aimed to test the predictive value of noncriteria antiphospholipid antibodies (aPL) in addition to the global antiphospholipid syndrome score (GAPSS) in predicting vascular thrombosis (VT) in a cohort of patients with APS and aPL (+) systemic lupus erythematosus (SLE).

Material and methods

This study included 50 patients with primary APS, 68 with SLE/APS, and 52 with aPL (+) SLE who were classified according to VT as VT ± pregnancy morbidity (PM), PM only or aPL (+) SLE. Antiphospholipid serology consisting of lupus anticoagulant (LA), anticardiolipin (aCL) immunoglobulin G (IgG)/IgM/IgA, antibeta2 glycoprotein I (aβ2GPI) IgG/IgM/IgA, antiphosphatidylserine/prothrombin (aPS/PT) IgG/IgM and antidomain-I (aDI) IgG was determined for each patient. The GAPSS and adjusted GAPSS (aGAPSS) were calculated for each patient, as previously defined. Logistic regression analysis was carried out with thrombosis as the dependent variable and high GAPSS, aCL IgA, aβ2GPI IgA, and aDI IgG as independent variables.

Results

The mean GAPSS and aGAPSS of the study population were 11.6 ± 4.4 and 9.6 ± 3.8. Both the VT ± PM APS (n = 105) and PM only APS (n = 13) groups had significantly higher GAPSS and aGAPSS values compared to the aPL (+) SLE (n = 52) group. The patients with recurrent thrombosis had higher aGAPSS but not GAPSS than those with a single thrombotic event. The computed area under the receiver operating characteristic curve demonstrated that a GAPSS ≥13 and aGAPSS ≥10 had the best predictive values for thrombosis. Logistic regression analysis including a GAPSS ≥13, aCL IgA, aβ2GPI IgA, and aDI IgG showed that none of the factors other than a GAPSS ≥13 could predict thrombosis.

Conclusion

Both the GAPSS and aGAPSS successfully predict the thrombotic risk in aPL (+) patients and aCL IgA, aβ2GPI IgA, and aDI IgG do not contribute to high a GAPSS or aGAPSS.

Global Antiphospholipid Syndrome Score (GAPSS) in Patients with Systemic Lupus Erythematosus

The Global Antiphospholipid Syndrome Score (GAPSS) is a tool proposed to quantify the risk of clinical manifestations associated with antiphospholipid antibodies (aPL) and certain cardiovascular risk factors. To validate GAPSS in a cohort of patients with systemic lupus erythematosus in Russia. 115 patients with SLE were included in the study, including 51 (44%) patients with systemic lupus erythematosus (SLE) with antiphospholipid syndrome (APS), 14 (12%) SLE patients with aPL, and 50 (44%) patients with SLE. There was a history of thrombosis in 58 (50%) out of 115 patients; of them, 14 (24%) had arterial thrombosis, 29 (50%) had venous thrombosis, and 15 (26%) had combined thrombosis. Pregnancy against the background of the disease occurred in 43 women included in the study. Of them, 29 (67%) had obstetric pathology. Patients with thrombosis and obstetric pathology had a GAPSS score of 7.17 ± 5.64 versus 4.48 ± 4.55 without these manifestations (p = 0.0003). There was a significant association between GAPSS levels and thrombosis: patients with thrombosis had a GAPSS of 7.31 ± 5.70, those without thrombosis-4.00 ± 4.81 (p = 0.001). GAPPS values were higher in arterial thrombosis compared to venous thrombosis (10.40 ± 25.30 versus 5.82 ± 5.28, p = 0.01). GAPSS levels  ≥ 6 and  ≥10 were analyzed to select GAPSS values at which a high risk of recurrent thrombosis and/or obstetric pathology could be indicated. All GAPSS levels had a significant association with clinical manifestations of APS. The quality of GAPSS by ROC analysis showed an area under the curve (AUC) for GAPSS of 0.697. GAPSS can be used to assess the risk of recurrence or development of thrombosis and/or obstetric pathology in patients with SLE in the Russian Federation. The GAPSS ≥6 values should be used to stratify patients with SLE into high risk group for recurrence of vascular complications. Further prospective follow-up is needed to confirm the value of GAPSS.

Global Antiphospholipid Syndrome Score (GAPSS) in patients with primary antiphospholipid syndrome

Stratification of patients into groups of high and low risk of adverse outcome is necessary for timely and early prevention of the disease, as well as the selection of adequate therapy.Objective: to validate the global risk scale for the development of clinical manifestations of antiphospholipid syndrome (GAPSS) in a cohort of patients with primary antiphospholipid syndrome (PAPS).Material and methods. The study included 64 patients with PAPS. Data on clinical manifestations, traditional cardiovascular risk factors, and antiphospholipid antibody profile were collected. GAPSS values were calculated for each patient by summing the scores corresponding to risk factors as follows: 3 points – for hyperlipidemia; 1 point – for arterial hypertension; 5 points – for antibodies to cardiolipin (aCL) IgG/IgM; 4 points – for antibodies to â2-glycoprotein 1 (anti-â2GP1) IgG/IgM and 3 points – for antibodies to the phosphatidylserine-prothrombin complex (aPS/PT) IgG/IgM.Results and discussion. GAPSS indicators were comparable in women and men with PAPS – 12.0 [9.0; 13.0] points. GAPSS values did not differ in patients with thrombosis and obstetric pathology: in thrombosis they were 10.0±4.46 (range 0.0–14.0) points, in obstetric pathology – 9.26±5.08 (range 0.0–14.0) points.The localization of thrombosis did not affect the GAPSS values, which reached 9.23±5.21 points in arterial thrombosis, 10.44±4.01 points in venous thrombosis, and 10.33±4.18 points in combined ones. Patients with recurrent thrombosis had higher GAPSS scores compared to patients without relapse: 8.19±5.25 points versus 11.00±3.65 points (p=0.01). There were no significant differences in GAPSS scores in obstetric pathology at different gestational ages.GAPSS values ≥6 showed a higher risk of thrombosis recurrence: odds ratio 5.23 (95% CI 1.34–20.37). GAPSS scores ≥6 demonstrated the highest accuracy, with sensitivity and specificity of 72% and 66%, respectively. According to ROC analysis, the AUC value for GAPSS was 0.675 (95% CI 0.542–0.808; p=0.01).Conclusion. The use of GAPSS makes it possible to identify patients at increased risk of recurrent thrombosis. GAPSS scores ≥6 have high sensitivity (72%) and specificity (66%), which can be used to stratify patients with PAPS into high and low risk groups for recurrent thrombosis.

Global antiphospholipid syndrome score (GAPSS) in patients with systemic lupus erythematosus

Introduction. The Global Antiphospholipid Syndrome Score (GAPSS) is a tool proposed to quantify the risk of clinical manifestations associated with antiphospholipid antibodies (aPL) and certain cardiovascular risk factors.

Objective. To validate GAPSS in a cohort of patients with systemic lupus erythematosus in Russia.

Material and methods. 115 patients with SLE were included in the study, including 51 (44%) patients with systemic lupus erythematosus (SLE) with antiphospholipid syndrome (APS), 14 (12%) – SLE with aPL, and 50 (44%) – SLE.

Results. There was a history of thrombosis in 58 (50%) patients with 115, of them 14 (24%) had arterial thrombosis, 29 (50%) – venous, 15 (26%) – combined. Pregnancy against the background of the disease occurred in 43 women included in the study. Of them, 29 (67%) had obstetric pathology. Patients with thrombosis and obstetric pathology had a GAPSS score of 7.17±5.64, versus 4.48±4.55 without these manifestations (p=0.0003). There was a significant association between GAPSS levels and thrombosis – patients with thrombosis had a GAPSS of 7.31±5.70, those without thrombosis – 4.00±4.81 (p=0.001). GAPPS values were higher in arterial thrombosis compared to venous thrombosis (10.40±25.30 versus 5.82±5.28; p=0.01). GAPSS levels ≥6 and ≥10 were analyzed to select GAPSS values at which a high risk of recurrent thrombosis and/or obstetric pathology could be indicated. All GAPSS levels had a significant association with clinical manifestations of APS. The quality of GAPSS by ROC analysis showed an area under the curve (AUC) for GAPSS of 0.697.

Conclusion. GAPSS can be used to assess the risk of recurrence or development of thrombosis and/or obstetric pathology in patients with SLE in the Russian Federation. The GAPSS ≥6 values should be used to stratify patients with SLE into high risk group for recurrence of vascular complications. Further prospective follow-up is needed to confirm the value of GAPSS.

Clinical and therapeutic value of the adjusted Global Antiphospholipid Syndrome Score in primary obstetric antiphospholipid syndrome

OBJECTIVES

(1) To assess the clinical utility of the adjusted global antiphospholipid syndrome score (aGAPSS) to predict new obstetric events during follow-up in primary obstetric antiphospholipid syndrome (POAPS) patients under standard-of-care treatment (SC) based on the use of low-dose aspirin (LDA) + heparin and (2) to study the risk of a first thrombotic event and to evaluate whether stratification according to this score could help to identify POAPS patients who would benefit from long-term thromboprophylaxis.

METHODS

This is a retrospective, multicentre study. 169 women with POAPS were evaluated for the presence of a new obstetric event and/or a first thrombotic event during follow-up [time period: 2008-2020, median: 7 years (6-12 years)]. The outcomes of 107 pregnancies from these POAPS patients with SC were studied to evaluate relapses. Simple and multivariable logistic regression analyses were performed.

RESULTS

Regarding obstetric morbidity, only triple positivity for antiphospholipid antibodies (aPLs) [OR = 8.462 (95% CI: 2.732-26.210); p < 0.0001] was found to be a strong risk factor independently associated with treatment failure. On the other hand, triple positivity for aPLs [OR=10.44 (95% CI: 2.161-50.469), p = 0.004] and an aGAPSS ≥7 [OR = 1.621 (95% CI: 1.198-2.193), p = 0.002] were independent risk factors associated with a first thrombotic event. LDA was marginally associated with a decrease in the risk of thrombosis only in patients with aGAPSS ≥ 7 (p = 0.048).

CONCLUSION

aGAPSS appears to be useful in predicting the occurrence of a first thrombotic event in POAPS patients, and these stratification of patients could be helpful in selecting patients who would benefit from thromboprophylaxis with LDA.

Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review

Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity associated with persistent antiphospholipid antibody positivity. Cases fulfilling the Sydney criteria for obstetric morbidity with no previous thrombosis are known as obstetric antiphospholipid syndrome (OAPS). OAPS is the most identified cause of recurrent pregnancy loss and late-pregnancy morbidity related to placental injury. Cases with incomplete clinical or laboratory data are classified as obstetric morbidity APS (OMAPS) and non-criteria OAPS (NC-OAPS), respectively. Inflammatory and thrombotic mechanisms are involved in the pathophysiology of OAPS. Trophoblasts, endothelium, platelets and innate immune cells are key cellular players. Complement activation plays a crucial pathogenic role. Secondary placental thrombosis appears by clot formation in response to tissue factor activation. New risk assessment tools could improve the prediction of obstetric complication recurrences or thromboses. The standard-of-care treatment consists of low-dose aspirin and prophylactic low molecular weight heparin. In refractory cases, the addition of hydroxychloroquine, low-dose prednisone or IVIG improve pregnancy outcomes. Statins and eculizumab are currently being tested for treating selected OAPS women. Finally, we revisited recent insights and concerns about the pathophysiology, diagnosis and management of OAPS.

Does Adjusted Global Antiphospholipid Syndrome Score (aGAPSS) Predict the Obstetric Outcome in Antiphospholipid Antibody Carriers? A Single-Center Study

The adjusted Global Antiphospholipid Syndrome (APS) Score (aGAPSS) is a tool proposed to quantify the risk for antiphospholipid antibody (aPL)-related clinical manifestations. However, aGAPSS has been validated mainly for thrombotic events and studies on APS-related obstetric manifestations are scarce. Furthermore, the majority of them included patients with positive aPL and different autoimmune diseases. Here, we assess the utility of aGAPSS to predict the response to treatment in aPL carriers without other autoimmune disorders. One-hundred and thirty-seven women with aPL ever pregnant were included. Sixty-five meet the APS classification criteria, 61 had APS-related obstetric manifestations, and 11 were asymptomatic carriers. The patients' aGAPSS risk was grouped as low (< 6, N = 73), medium (6-11, N = 40), and high risk (≥ 12, N = 24). Since vascular risk factors included in the aGAPSS were infrequent in this population (< 10%), the aGAPSS score was mainly determined by the aPL profile. Overall, the live birth rate was 75%, and 37.2% of the patients had at least one adverse pregnancy outcome (APO). When considering patients according to the aGAPSS (high, medium, and low risk), no significant differences were found for pregnancy loss (29.2%, 25%, and 21.9%) or APO (33.3%, 47.5%, and 32.9%). In the present study, including aPL carriers without other autoimmune diseases, aGAPSS is not a valuable tool to identify patients at risk for obstetric complications despite treatment. In these patients with gestational desire, in addition to the aPL profile, other pregnancy-specific factors, such as age or previous obstetric history, should be considered.

Coronavirus disease 2019 (COVID-19) and immune-mediated inflammatory rheumatic diseases: at the crossroads of thromboinflammation and autoimmunity

Inflammation and coagulation are key basic mechanism of protection against all potentially pathogenic mechanical and biological factors targeting human organism from inner and outer environment. On the other hand, uncontrolled inflammation results in hypercoagulation, inhibition of anticoagulation and alteration of mechanisms responsible for resolution of inflammation, while production of “procoagulant” mediators (thrombin, tissue factor and others), activation of platelets and of vascular endothelial cells maintains inflammation. All factors taken together serve as the basis for a pathological process called thromboinflammation or immunothrombosis. Currently thromboinflammation is considered in the broad sense as a universal pathogenetic mechanism of numerous widespread acute and chronic conditions, including immune-mediated (autoimmune) inflammatory rheumatic diseases, oftentimes complicated by severe irreversible damage to vital organs. Thromboinflammation gained specific attention during СОVID-19 (coronavirus disease 2019) pandemic, caused by SARS-Cov-2 (severe acute respiratory syndrome Coronavirus-2). COVID-19 is considered currently as systemic thromboinflammation syndrome, manifesting via generalized thrombosis of arterial and venous macro- and microvasculature, termed as COVID-19-coagulopathy. The paper discusses common pathogenetic coagulopathy mechanisms in COVID-19 and immune-mediated (autoimmune) inflammatory rheumatic diseases (IMRDs), associated with overproduction of antiphospholipid antibodies, activation of the complement system, and dis-regulated synthesis of proinflammatory cytokines, etc. Delineating the autoimmune subtype of thromboinflammation, identification of genetic (i.e., genes encoding the complement system and others) and molecular-biologic biomarkers associated with higher occurrence of COVID-19-coagulopathy are the most relevant undertakings for the current practice. Gaining insights into mechanisms of thromboinflammation and converting them into potential pharmacotherapies of IMDs would facilitate and accelerate the drafting of effective therapeutic strategies for COVID-19. 

Validation of the adjusted global antiphospholipid syndrome score in a single centre cohort of APS patients from Turkey

The adjusted global antiphospholipid syndrome score (aGAPSS) is a recently developed thrombotic risk assessment score that considers the antiphospholipid antibody (aPL) profile and conventional cardiovascular risk factors. In this retrospective study, we aimed to evaluate the validity of the aGAPSS in predicting clinical manifestations (criteria and extra-criteria) of antiphospholipid syndrome (APS) in a single centre cohort of patients. Ninety-eight patients with APS ± systemic lupus erythematosus (SLE) were classified according to clinical manifestations as vascular thrombosis (VT), pregnancy morbidity (PM) or both (VT + PM). The aGAPSS was calculated for each patient as previously defined. Mean aGAPSS of the cohort was calculated as 10.2 ± 3.8. Significantly higher aGAPSS values were seen in VT (n = 58) and VT + PM (n = 29) groups when compared to PM (n = 11) group (10.6 ± 3.7 vs 7.4 ± 2.9, P = 0.005; 10.7 ± 4 vs 7.4 ± 2.9, P = 0.008, respectively), mainly due to lower frequencies of cardiovascular risk factors in PM. Higher aGAPPS values were also associated with recurrent thrombosis (11.6 ± 3.7 vs 9.9 ± 3.6, P = 0.04). Regarding extra-criteria manifestations, patients with livedo reticularis (n = 11) and APS nephropathy (n = 9) had significantly higher aGAPSS values (12.9 ± 3.4 vs 9.9 ± 3.7, P = 0.02; 12.4 ± 2.9 vs 10 ± 3.8, P = 0.04, respectively). The computed AUC demonstrated that aGAPSS values ≥10 had the best diagnostic accuracy for thrombosis. Our results suggest that patients with higher aGAPSS values are at higher risk for developing vascular thrombosis (either first event or recurrence) and extra-criteria manifestations, especially livedo reticularis and APS nephropathy.

Global antiphospholipid syndrome score and anti-ß2-glycoprotein I domain I for thrombotic risk stratification in antiphospholipid syndrome: A four-year prospective study

Objective

This study aimed to assess prospectively the role of anti-ß2-glycoprotein I domain I antibody (aß2GPI-DI) and the Global Antiphospholipid Syndrome Score (GAPSS) in identifying antiphospholipid syndrome (APS) patients at higher risk of a new event.

Methods

Thrombotic APS patients were followed from May 2013 to July 2017. At baseline, we measured lupus anticoagulant, IgG/IgM anticardiolipin, anti-ß2-glycoprotein I, antiphosphatidylserine-prothrombin (aPS/PT) and IgG aß2GPI-DI, and calculated GAPSS for each patient.

Results

A total of 44 patients (age 43 ± 10 years, 89% female, 73% primary APS) were followed for 39 months (range 9–46 months). Four new thromboses occurred, two of them after vitamin K antagonist interruption. Recurrent patients presented higher GAPSS (median 20) and were triple and aß2GPI-DI positive; non-recurrent patients had lower GAPSS (median 10.5, range 0–20) and lower ratio of triple (33%) and aß2GPI-DI positivities (38%). aß2GPI-DI was associated with higher GAPSS (median 19 vs. 7, p < 0.001; Pearson correlation 0.82, p < 0.001) and had a greater proportion of triple (83% vs. 4%, p < 0.001) and aPS/PT positivity (94% vs. 50%, p = 0.002).

Conclusion

Our data show a significant correlation between a validated risk score such as GAPSS and the novel antiphospholipid antibody aß2GPI-DI. Future studies are needed. However, one could speculate a role of aß2GPI-DI as a risk-stratifying tool for thrombotic events in APS.

Improvements in diagnosis and risk assessment of primary and secondary antiphospholipid syndrome

Classification criteria for antiphospholipid syndrome have not been updated since the revised Sapporo classification criteria were published in 2006. These criteria have limitations in that they omit nonclassical manifestations (hematologic and neurologic), include anticardiolipin and anti-β2-glycoprotein I immunoglobulin (Ig)M isotypes, and do not separately consider primary (no autoimmune disease) or secondary (usually systemic lupus erythematosus) disease. Recent findings in antiphospholipid antibody include fluctuation of antiphospholipid antibodies, recognition that IgA isotypes do confer risk, identification of the role of complementopathy in catastrophic antiphospholipid syndrome, and elucidation of the role of thrombosis risk equations.

The adjusted global antiphospholipid syndrome score (aGAPSS) and the risk of recurrent thrombosis: Results from the APS ACTION cohort

OBJECTIVES

To assess whether patients with antiphospholipid syndrome (APS) and history of recurrent thrombosis have higher levels of adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) when compared to patients without recurrent thrombosis.

METHODS

In this cross-sectional study of antiphospholipid antibody (aPL)-positive patients, we identified APS patients with a history of documented thrombosis from the AntiPhospholipid Syndrome Alliance For Clinical Trials and InternatiOnal Networking (APS ACTION) Clinical Database and Repository ("Registry"). Data on aPL-related medical history and cardiovascular risk factors were retrospectively collected. The aGAPSS was calculated at Registry entry by adding the points corresponding to the risk factors: three for hyperlipidemia, one for arterial hypertension, five for positive anticardiolipin antibodies, four for positive anti-β2 glycoprotein-I antibodies and four for positive lupus anticoagulant test.

RESULTS

The analysis included 379 APS patients who presented with arterial and/or venous thrombosis. Overall, significantly higher aGAPSS were seen in patients with recurrent thrombosis (arterial or venous) compared to those without recurrence (7.8 ± 3.3 vs. 6 ± 3.9, p<0.05). When analyzed based on the site of the recurrence, patients with recurrent arterial, but not venous, thrombosis had higher aGAPSS (8.1 ± SD 2.9 vs. 6 ± 3.9; p<0.05).

CONCLUSIONS

Based on analysis of our international large-scale Registry of aPL-positive patients, the aGAPSS might help risk stratifying patients based on the likelihood of developing recurrent thrombosis in APS.

Clinical profiles and risk assessment in patients with antiphospholipid antibodies

INTRODUCTION

Antiphospholipid syndrome (APS) is an acquired autoimmune thrombophilia associated with the presence of persistent antiphospholipid antibodies (aPL). Owing to recent studies, not only APS patients but also incidentally-identified, asymptomatic aPL carriers are able to be stratified in terms of the risk of future thrombotic events, according to the variety and the titer of positive aPL tests and to the non-thrombotic, aPL-associated clinical manifestations. Areas covered: Here, we critically review (1) criteria manifestations of APS, (2) non-criteria manifestations of APS, (3) risk assessment in patients with APS and in aPL carriers, and (4) the potential role of primary thrombosis prophylaxis in aPL carriers. In addition, we discuss what we are currently able to do and what we need to do in the future for primary prophylaxis against a first thrombotic event. Expert commentary: We suggest a comprehensive algorithm to stratify thrombotic risk in aPL carriers, including criteria aPL, non-criteria aPL, their scoring systems, and non-criteria manifestations. However, further studies, particularly prospective randomized controlled trials, are highly warranted to establish an effective and tolerable treatment regimen for high risk aPL carriers.

The association of adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) with cardiovascular disease in subjects with antiphospholipid antibodies

BACKGROUND AND AIMS

Cardiovascular disease (CVD), including coronary artery disease and stroke/peripheral artery disease, is less commonly reported than venous thromboembolism in subjects with antiphospholipid antibodies (aPLs) and little is known about the association of CVD with adjusted Global AntiphosPholipid Syndrome Score (aGAPSS).

METHODS

Consecutive aPLs subjects were enrolled to assess the association of CVD with aGAPSS. Moreover, additional risk factors of CVD were identified by means of multivariate analysis to design an aGAPSS specific for CVD (aGAPSS_CVD).

RESULTS

A total of 192 aPLs subjects (34 males, 158 females, mean age 49.84 ± 12.0 years) were enrolled. CVD was reported in 52 subjects (27.1%), 26 episodes of coronary artery disease and 26 stroke/peripheral artery disease. The prevalence of CVD increased for increasing aGAPSS ranging from 20.5% in the lowest aGAPSS category, up to 37.9% in the highest category (p = 0.027). ROC analysis showed that aGAPSS detected 63.0% of CVD and was associated with OR for CVD of 2.52 (95%CI: 1.24-5.10, p = 0.010). When including obesity, diabetes and smoking habit in the score, we found that aGAPSSCVD detected 71.4% of CVD (72.4% for early-CVD and 69.0% for CVD after 50 years) with an OR for CVD of 4.68 (95%CI: 2.31-9.51, p < 0.001).

CONCLUSIONS

The aGAPSS_CVD, obtained after adding obesity, smoking habit and diabetes to the standard aGAPSS, showed a higher detection rate of CVD in aPLs subjects, particularly of early-CVD. These results need to be validated in ad hoc designed prospective studies.

Added value of non-criteria antiphospholipid antibodies for antiphospholipid syndrome: lessons learned from year-long routine measurements

The international classification criteria for definite antiphospholipid syndrome (APS) include three laboratory measurements: lupus anticoagulant (LA), IgG and IgM isotypes of anti-cardiolipin (aCL) and anti-β2glycoprotein I antibodies (anti-β2GPI). When persistently elevated, they are specific for APS; however, many patients that fulfil clinical criteria may exhibit negative serological results. These "seronegative" APS (SN-APS) are exposed to an increased thrombotic risk. The aims of our cross-sectional, retrospective study of consecutive autoimmune patients' samples were to evaluate the association of non-criteria antiphospholipid antibodies (aPL) with thrombosis and obstetric events, to calculate the risk score for adverse events and to assess the specific contribution of single aPL positivity in SN-APS. LA, aCL, anti-β2GPI and anti-phosphatidylserine/prothrombin antibodies (aPS/PT) of IgG, IgM, and IgA isotypes were determined in sera of 323 patients with autoimmune disorders. Medical records of all patients were carefully analyzed. aCL, anti-β2GPI and aPS/PT of IgG and IgA isotypes were significantly associated with thrombosis while none of the IgM aPL showed such association. aPS/PT of all isotypes, aCL and anti-β2GPI of IgG and IgA isotype showed significant correlation to obstetric events. When considering results of aPS/PT ELISA, we could additionally identify 3% of thrombotic patients and 2% of obstetric patients. Thrombotic and obstetric risk scores were calculated showing significantly higher association to clinical events, as compared to evaluating individual risk factors. aPS/PT could represent an additional biomarker in SN-APS patients. IgA aPL are associated with thrombosis and obstetric complications. Risk scores accounting different aPL and conventional risk factors, better assesses risk for adverse event, as compared to evaluating individual factors alone.

Clinical utility of the global anti-phospholipid syndrome score for risk stratification: a pooled analysis

Objective

Recently, our group conceived a risk score for clinical manifestations of APS (the global APS score, or GAPSS) that takes into account the combination of independent cardiovascular risk factors and the aPL positivity profile. These include hyperlipidaemia, arterial hypertension, aCL, anti-β2 glycoprotein-I, aPS-PT and the LA. A complementary version, the adjusted GAPSS (aGAPSS), which excludes aPS-PT, was also designed. The aim of our study was to systematically review the literature to assess the clinical utility of the GAPSS and aGAPSS for risk stratification of any APS clinical manifestation.

Methods

We pooled data from available cohort studies, including a total of 10 studies, comprising 2273 patients, in which the GAPSS has been applied. A search strategy was developed a priori to identify an available cohort that reported findings which investigated the clinical utility of GAPSS or aGAPSS.

Results

Seven studies used the GAPSS in their cohort, whereas three studies used the aGAPSS. In brief, we found a statistically significant difference in the cumulative GAPSS and aGAPSS between patients that experienced an arterial and/or venous thrombotic event [cumulative mean GAPSS (s.d.) 10.6 (4.74) and aGAPSS 7.6 (3.95)], patients without any thrombotic manifestation [cumulative GAPSS 7.01 (5.46) and aGAPSS 4.9 (4.33)] and patients with pregnancy morbidity [cumulative GAPSS 8.79 (2.59) and aGAPSS 6.7 (2.8)]. The highest levels of GAPSS were found in patients that experienced arterial thrombosis [mean GAPSS 12.2 (5.2)] and patients that experienced any recurrences of clinical manifestations of APS [mean GAPSS 13.7 (3.1)].

Conclusion

GAPSS may represent a useful tool to assess the thrombosis or pregnancy loss risk in aPL-positive patients, switching from the concept of aPL as a sole diagnostic antibody to aPL as risk factors for clinical events.

How to Identify High-Risk APS Patients: Clinical Utility and Predictive Values of Validated Scores

PURPOSE OF REVIEW

Antiphospholipid syndrome (APS) is a clinical disorder characterised by thrombosis and/or pregnancy morbidity in the persistence of antiphospholipid (aPL) antibodies that are pathogenic and have pro-coagulant activities. Thrombosis in APS tends to recur and require prophylaxis; however, the stereotypical treatment for APS patients is inadequate and stratification of the thrombotic risks is important as aPL are prevalently observed in various diseases or elderly population.

RECENT FINDINGS

It is previously known that the multiple positive aPL or high titre aPL correlate to thrombotic events. To progress the stratification of thrombotic risks in APS patients and to quantitatively analyse those risks, antiphospholipid score (aPL-S) and the Global Anti-phospholipid Syndrome Score (GAPSS) were defined. These scores were raised from the large patient cohort data and either aPL profile classified in detail (aPL-S) or simplified aPL profile with classical thrombotic risk factors (GAPSS) was put into a scoring system. Both the aPL-S and GAPSS have shown a degree of accuracy in identifying high-risk APS patients, especially those at a high risk of thrombosis. However, there are several areas requiring improvement, or at least that clinicians should be aware of, before these instruments are applied in clinical practice. One such issue is standardisation of the aPL tests, including general testing of phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT). Additionally, clinicians may need to be aware of the patient's medical history, particularly with respect to the incidence of SLE, which influences the cutoff value for identifying high-risk patients.

Clinical Risk Assessment in the Antiphospholipid Syndrome: Current Landscape and Emerging Biomarkers

PURPOSE OF REVIEW

Laboratory criteria for the classification of antiphospholipid syndrome include the detection of a lupus anticoagulant and/or anticardiolipin and anti-β2-glycoprotein I antibodies. However, the majority of patients who test positive in these assays do not have thrombosis. Current risk-stratification tools are largely limited to the antiphospholipid antibody profile and traditional thrombotic risk factors.

RECENT FINDINGS

Novel biomarkers that correlate with disease activity and potentially provide insight into future clinical events include domain 1 specific anti-β₂GPI antibodies, antibodies to other phospholipids or phospholipid/protein antigens (such as anti-PS/PT), and functional/biological assays such as thrombin generation, complement activation, levels of circulating microparticles, and annexin A5 resistance. Clinical risk scores may also have value in predicting clinical events. Biomarkers that predict thrombosis risk in patients with antiphospholipid antibodies have been long sought, and several biomarkers have been proposed. Ultimately, integration of biomarkers with established assays and clinical characteristics may offer the best chance of identifying patients at highest risk of APS-related complications.

Antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by the presence of antiphospholipid antibodies, such as lupus anticoagulant, anticardiolipin antibodies and anti-β2-glycoprotein 1 antibodies. APS can present with a variety of clinical phenotypes, including thrombosis in the veins, arteries and microvasculature as well as obstetrical complications. The pathophysiological hallmark is thrombosis, but other factors such as complement activation might be important. Prevention of thrombotic manifestations associated with APS includes lifestyle changes and, in individuals at high risk, low-dose aspirin. Prevention and treatment of thrombotic events are dependent mainly on the use of vitamin K antagonists. Immunosuppression and anticomplement therapy have been used anecdotally but have not been adequately tested. Pregnancy morbidity includes unexplained recurrent early miscarriage, fetal death and late obstetrical manifestation such as pre-eclampsia, premature birth or fetal growth restriction associated with placental insufficiency. Current treatment to prevent obstetrical morbidity is based on low-dose aspirin and/or low-molecular-weight heparin and has improved pregnancy outcomes to achieve successful live birth in >70% of pregnancies. Although hydroxychloroquine and pravastatin might further improve pregnancy outcomes, prospective clinical trials are required to confirm these findings.

Extra-criteria manifestations of antiphospholipid syndrome: Risk assessment and management

OBJECTIVES

Extra-criteria manifestations of antiphospholipid syndrome (APS) might impact on prognosis and morbidity of the disease. In this study, we aimed to evaluate a population of patients with primary APS (PAPS) whether the extra-criteria manifestations were more frequently found in subjects with higher adjusted Global APS Score (aGAPSS) values when compared to patients with thrombotic and/or obstetric APS ("criteria" manifestations) only.

METHODS

Clinical records were analyzed to retrieve extra-criteria manifestation of APS, cardiovascular risk factors and antiphospholipid antibodies profile. The aGAPSS was calculated by adding the points, as follows: 3 for hyperlipidaemia, 1 for arterial hypertension, 5 for anticardiolipin antibodies IgG/IgM, 4 for anti-β2 glycoprotein I IgG/IgM, and 4 for lupus anticoagulant.

RESULTS

This retrospective multicenter study included 89 consecutive PAPS [mean age 43.1 (S.D. ± 12.9), female 67%, 52% arterial and 65% venous]. Twenty-seven patients (30.3%) had a history of livedo, 19 (21.3%) had a history of confirmed thrombocytopenia, 3 (3.4%) had biopsy-proven antiphospholipid antibodies (aPL)-related nephropathy and 3 (3.4%) had a history of valvulopathy. Patients with extra-criteria manifestations presented a mean aGAPSS significantly higher [mean 10.30 (S.D. ± 3.57, range: 4-17) vs mean 8.16 (S.D. ± 3.52;range: 4-16, p = 0.005). When comparing patients with and without extra-criteria manifestations, the first group had significantly higher incidence of anti-β2GPI antibodies positivity (59% and 33%, respectively, p = 0.015), double aPL positivities (53% and 31%, respectively, p = 0.034), cerebrovascular events history (52% and 24%, respectively, p = 0.007) and arterial hypertension (52% and 24%, respectively, p = 0.007).

CONCLUSIONS

Our results suggest that patients with higher aGAPSS, might be at higher risk for developing extra-criteria manifestations of APS and should therefore undergo a thorough laboratory and instrumental evaluation.

Diagnosing antiphospholipid syndrome: 'extra-criteria' manifestations and technical advances

First described in the early 1980s, antiphospholipid syndrome (APS) is a unique form of acquired autoimmune thrombophilia in which patients present with clinical features of recurrent thrombosis and pregnancy morbidity and persistently test positive for the presence of antiphospholipid antibodies (aPL). At least one clinical (vascular thrombosis or pregnancy morbidity) and one lab-based (positive test result for lupus anticoagulant, anticardiolipin antibodies and/or anti-β2-glycoprotein 1 antibodies) criterion have to be met for a patient to be classified as having APS. However, the clinical spectrum of APS encompasses additional manifestations that can affect many organs and cannot be explained exclusively by patients being in a prothrombotic state; clinical manifestations not listed in the classification criteria (known as extra-criteria manifestations) include neurologic manifestations (chorea, myelitis and migraine), haematologic manifestations (thrombocytopenia and haemolytic anaemia), livedo reticularis, nephropathy and valvular heart disease. Increasingly, research interest has focused on the development of novel assays that might be more specific for APS than the current aPL tests. This Review focuses on the current classification criteria for APS, presenting the role of extra-criteria manifestations and lab-based tests. Diagnostic approaches to difficult cases, including so-called seronegative APS, are also discussed.

Diagnosis and management of the antiphospholipid syndrome

Antiphospholipid syndrome (APS) is characterized by thrombosis and/or pregnancy complications in the presence of persistent antiphospholipid antibodies (APLA). Laboratory diagnosis of APLA depends upon the detection of a lupus anticoagulant, which prolongs phospholipid-dependent anticoagulation tests, and/or anticardiolipin (aCL) and anti-β2-glycoprotein-1 (β2GPI) antibodies. APLA are primarily directed toward phospholipid binding proteins. Pathophysiologic mechanisms underlying thrombosis and pregnancy loss in APS include APLA induced cellular activation, inhibition of natural anticoagulant and fibrinolytic systems, and complement activation, among others. There is a high rate of recurrent thrombosis in APS, especially in triple positive patients (patients with lupus anticoagulant, aCL and anti-β2GPI antibodies), and indefinite anticoagulation with a vitamin K antagonist is the standard of care for thrombotic APS. There is currently insufficient evidence to recommend the routine use of direct oral anticoagulants (DOAC) in thrombotic APS. Aspirin with low molecular weight or unfractionated heparin may reduce the incidence of pregnancy loss in obstetric APS. Recent insights into the pathogenesis of APS have led to the identification of new potential therapeutic interventions, including anti-inflammatory and immunomodulatory therapies. Additional research is needed to better understand the effects of APLA on activation of signaling pathways in vascular cells, to identify more predictive biomarkers that define patients at greatest risk for a first or recurrent APLA-related clinical event, and to determine the safety and efficacy of DOACs and novel anti-inflammatory and immune-modulatory therapies for refractory APS.

Independent validation of the adjusted GAPSS: Role of thrombotic risk assessment in the real-life setting

Objective

The objective of this report is to independently validate the adjusted Global Antiphospholipid Syndrome Score (aGAPSS) to predict thrombosis in a cohort of patients with APS and/or autoimmune disease.

Methods

This retrospective cohort study included 319 consecutive patients with APS and/or autoimmune disease. Data on clinical manifestations, conventional cardiovascular risk factors and aPL profile were collected. The aGAPSS was calculated for each patient by adding together the points corresponding to the risk factors.

Results

Among the 319 patients included (mean age: 48.0; SD 15.47), conducted over a mean period of 52 months (range: 19–394), 219 fulfilled the current APS classification criteria (PAPS diagnosed in 130 patients and APS associated autoimmune disease (aAPS) in 89 patients), and 100 patients with autoimmune disease without APS (AD). A total of 201 patients (63.0%) had a history of one or several thrombotic manifestations, 189 (86.3%) of them APS patients: 118 PAPS (mean age: 50.14; SD 15.47) and 71 aAPS (mean age: 48.13; SD 15.81). Higher aGAPSS baseline values were seen in patients with thrombosis 6.58 (SD 3.36) when compared with those without 4.90 (SD 4.33) ( p = 0.001).

Conclusions

This study has shown that even when anti-phosphatidylserine/prothrombin antibodies (aPS/PT) are not computed in an adjusted model of GAPSS (aGAPSS), this score represents an improvement in assessment of the risk prediction of thrombosis in APS patients and/or autoimmune disease. However, cut-off values may differ from other kinds of cohorts, which suggests that baseline characteristics in divergent groups of patients can account for differences in cut-off values of GAPSS.

The adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) for risk stratification in young APS patients with acute myocardial infarction

BACKGROUND

Young adults with acute myocardial infarction are a critical group to examine for the purpose of risk factor stratification and modification. In this study we aimed to assess the clinical utility of the adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) for the risk stratification of acute myocardial infarction in a cohort of young patients with antiphospholipid syndrome (APS).

METHODS

The analysis included 83 consecutive APS patients (≤50years old) who presented with arterial or venous thromboembolic events. Data on cardiovascular risk factors and antiphospholipid antibodies (aPL) positivity were retrospectively collected. The aGAPSS was calculated by adding the points corresponding to the risk factors, based on a linear transformation derived from the ß-regression coefficient as follows: 3 for hyperlipidaemia, 1 for arterial hypertension, 5 for aCL IgG/IgM, 4 for anti-b2 glycoprotein I IgG/IgM and 4 for LA.

RESULTS

Higher aGAPSS values were observed in patients with acute myocardial infarction when compared to the others [mean aGAPSS 11.9 (S.D. 4.15, range 4-18) Vs. mean aGAPSS 9.2 (S.D. 5.1, range 1-17); T test: p<0.05]. Significantly higher aGAPSS values were also seen in patients with acute coronary syndrome compared to patients with a history of peripheral or cerebrovascular arterial thrombotic events [mean aGAPSS 11.9 (S.D. 4.15, range 4-18) Vs. mean aGAPSS 6.7 (S.D. 5.7, range 1-17); T test: P<0.005].

CONCLUSIONS

The aGAPSS is based upon a quantitative score and could aid risk stratifying APS patients younger than 50years for the likelihood of developing coronary thrombotic events and may guide pharmacological treatment for high-risk patients.

Recent advances in understanding antiphospholipid syndrome

Antiphospholipid syndrome (APS), also known as Hughes Syndrome, is a systemic autoimmune disease characterized by thrombosis and/or pregnancy morbidity in the presence of persistently positive antiphospholipid antibodies. A patient with APS must meet at least one of two clinical criteria (vascular thrombosis or complications of pregnancy) and at least one of two laboratory criteria including the persistent presence of lupus anticoagulant (LA), anticardiolipin antibodies (aCL), and/or anti-b2 glycoprotein I (anti-b2GPI) antibodies of IgG or IgM isotype at medium to high titres in patient’s plasma. However, several other autoantibodies targeting other coagulation cascade proteins (i.e. prothrombin) or their complex with phospholipids (i.e. phosphatidylserine/prothrombin complex), or to some domains of β2GPI, have been proposed to be also relevant to APS. In fact, the value of testing for new aPL specificities in the identification of APS in thrombosis and/or pregnancy morbidity patients is currently being investigated.

Thrombotic risk assessment in antiphospholipid syndrome: the role of new antibody specificities and thrombin generation assay

Antiphospholipid syndrome (APS) is an autoimmune condition characterized by the presence of antiphospholipid antibodies (aPL) in subjects presenting with thrombosis and/or pregnancy loss. The currently used classification criteria were updated in the international consensus held in Sidney in 2005. Vascular events seem to result of local procoagulative alterations upon triggers influence (the so called “second-hit theory”), while placental thrombosis and complement activation seem to lead to pregnancy morbidity. The laboratory tests suggested by the current classification criteria include lupus anticoagulant, a functional coagulation assay, and anticardiolipin and anti-β2-glycoprotein-I antibodies, generally detected by solid phase enzyme-linked immunosorbent assay. The real challenge for treating physicians is understanding what is the actual weight of aPL in provoking clinical manifestations in each case. As thrombosis has a multi-factorial cause, each patient needs a risk-stratified approach. In this review we discuss the role of thrombotic risk assessment in primary and secondary prevention of venous and arterial thromboembolic disease in patients with APS, focusing on new antibody specificities, available risk scoring models and new coagulation assays.

Validity of the global anti-phospholipid syndrome score to predict thrombosis: a prospective multicentre cohort study

OBJECTIVE

To investigate the validity of the global APS score (GAPSS) to predict thrombosis in patients with autoimmune diseases.

METHODS

This prospective cohort study included consecutive patients with aPL or SLE. aPL, aPS-PT and GAPSS were determined. A Cox proportional hazards model assessed the validity of GAPSS and identified other potential independent predictors of thrombosis.

RESULTS

One hundred and thirty-seven patients [43.5 (s.d. 15.4) years old; 107 women] were followed up for a mean duration of 43.1 (s.d. 20.7) months. Mean GAPSS was significantly higher in patients who experienced a thrombotic event compared with those without [10.88 (s.d. 5.06) vs 8.15 (s.d. 5.31), respectively, P = 0.038]. In univariate analysis, age [hazard ratio (HR) = 1.04 (95% CI 1.01, 1.08)] and GAPSS above 16 [HR = 6.86 (95% CI 1.90, 24.77)] were each significantly associated with thrombosis during follow-up, while history of arterial thrombosis [HR = 2.61 (95% CI 0.87, 7.82)] failed to reach significance. Among aPL assays, IgG aPS/PT--a component of the GAPSS--was significantly associated with thrombosis [HR = 2.95 (95% CI 1.02, 8.51)]. In multivariate analysis, GAPSS above 16 remained the only significant predictor of thrombosis [HR = 6.17 (95% CI 1.70, 22.40)].

CONCLUSION

This first external validation study confirmed that GAPSS can predict thrombosis in patients with aPL and associated autoimmune diseases.