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Cited by 633Systemic Lupus Erythematosus ResearchBlood Coagulation and Thrombosis MechanismsVenous Thromboembolism Diagnosis and Management

Clinical course of high‐risk patients diagnosed with antiphospholipid syndrome

Open access
PENGO, V., RUFFATTI, A., LEGNANI, C., GRESELE, P., BARCELLONA, D., ERBA, N., TESTA, S., MARONGIU, F. +5 more·2010·Journal of Thrombosis and Haemostasis
DOI 10.1111/j.1538-7836.2009.03674.x
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Abstract

Background The characteristics and the clinical course of antiphospholipid syndrome (APS) in high-risk patients that are positive for all three recommended tests that detect the presence of antiphospholipid (aPL) antibodies have not been described. Methods This retrospective analysis of prospectively collected data examined patients referred to Italian Thrombosis Centers that were diagnosed with definite APS and tested positive for aPL [lupus anticoagulant (LA), anti-cardiolipin (aCL), and anti-beta2-glycoprotein I (beta2GPI) antibodies]. Laboratory data were confirmed in a central reference laboratory. Results One hundred and sixty patients were enrolled in this cohort study. The qualifying events at diagnosis were venous thromboembolism (76 cases; 47.5%), arterial thromboembolism (69 cases; 43.1%) and pregnancy morbidity (11 cases; 9.7%). The remaining four patients (2.5%) suffered from catastrophic APS. The cumulative incidence of thromboembolic events in the follow-up period was 12.2% (95% CI, 9.6-14.8) after 1 year, 26.1% (95% CI, 22.3-29.9) after 5 years and 44.2% (95% CI, 38.6-49.8) after 10 years. This was significantly higher in those patients not taking oral anticoagulants as compared with those on treatment (HR=2.4 95% CI 1.3-4.1; P<0.003). Major bleeding associated with oral anticoagulant therapy was low (0.8% patient/years). Ten patients died (seven were cardiovascular deaths). Conclusions Patients with APS and triple positivity for aPL are at high risk of developing future thromboembolic events. Recurrence remains frequent despite the use of oral anticoagulants, which significantly reduces the risk of thromboembolism.

AI snapshot

Written from the paper’s full text.

TL;DR

In 160 patients with definite antiphospholipid syndrome (APS) and triple positivity for lupus anticoagulant, anti-cardiolipin, and anti-β2-glycoprotein I antibodies, thromboembolic recurrence was frequent, with a cumulative incidence of 44.2% at 10 years. Oral anticoagulant treatment was associated with a significantly lower risk of recurrent thromboembolism, while major bleeding on anticoagulation was low.

Key findings

  • During follow-up, 55 of 160 patients (34.4%) had a thromboembolic event (25 venous, 30 arterial); cumulative incidence was 12.2% (95% CI 9.6–14.8) at 1 year, 26.1% (95% CI 22.3–29.9) at 5 years, and 44.2% (95% CI 38.6–49.8) at 10 years.
  • Oral anticoagulant status was the only predictor of thromboembolic events in multivariate Cox analysis: events occurred in 36/123 anticoagulated patients versus 19/37 non-anticoagulated patients, with HR 2.4 (95% CI 1.3–4.1; P < 0.003) for not taking oral anticoagulants; cumulative incidence was significantly higher in untreated patients (P = 0.002).
  • Major bleeding was low: 8 major bleeding events, 7 in patients on oral anticoagulants (0.8% patient/years); there were 10 deaths (0.8% patients/years; 7 cardiovascular, 3 non-cardiovascular).
  • Recurrence did not depend on the qualifying event: 10-year cumulative incidence was 45% for venous, 47% for arterial, and 37% for pregnancy morbidity as the qualifying event (P = ns).

Methods

  • Retrospective analysis of prospectively collected data from Italian Thrombosis Centers, including 160 patients with definite APS and triple positivity for LA, aCL, and anti-β2GPI antibodies, confirmed in a central reference laboratory; inclusion required LA and anti-β2GPI positivity and aCL > 40 GPL and/or > 40 MPL units.
  • Observation period from earliest diagnosis (March 1989) to March 2009; outcomes included objectively diagnosed thromboembolic events, major bleeding, and death.
  • Kaplan-Meier survival analysis estimated cumulative incidence of thromboembolic events; log-rank tests compared groups; Cox regression identified predictors of the primary endpoint.

Limitations

  • The paper does not include a formal limitations section; evident limitations include the observational, non-randomized treatment comparison (123 patients received long-term oral anticoagulants versus 37 who did not), so treatment effects may be confounded.
  • The cohort was selected from Thrombosis Centers and restricted to triple-positive APS patients with aCL > 40 units, limiting generalizability to other APS laboratory profiles or lower-risk populations.
  • Follow-up attrition was substantial: only 23 patients (14.4%) completed 10 years; pregnancy morbidity was uncommon (11 cases), and the reported percentage differs between the abstract (9.7%) and Results/Table 1 (6.9%).

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1111/j.1538-7836.2009.03674.x

Cites

41 of 41 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

3 of 23 cited sources checked · 1 supported · 0 flagged · accuracy not yet measured

  • Findingown data

    The present cohort differed from the Cervera et al. cohort in several respects.

    “This selected cohort of patients differed from the large cohort described by Cervera et al. [25,26] in several aspects.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [25] source
    • cites [26] source
  • Premisecitation

    No current evidence shows oral anticoagulants are superior to antiplatelet therapy.

    “As there is currently no evidence to support the superiority of oral anticoagulant therapy over antiplatelet therapy [15], antiplatelet drugs are generally recommended after an episode of stroke.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [15] source

      The COMMENT section reports that warfarin was not associated with fewer thrombo-occlusive events than aspirin in the studied stroke cohort. That supports the comparison, but the citing sentence generalizes it to all oral anticoagulants and antiplatelet therapies; the paper does not establish that broader claim. No page number is available in the supplied copy. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
  • Premisecitation

    Fewer than half of Cervera et al.'s patients were LA positive.

    “Less than half of the patients reported by Cervera et al. were LA positive.”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [25] source
    • cites [26] source

      The Laboratory studies section says LA activity was tested but gives no positivity rate. The General characteristics section says the cohort’s immunological findings were reported elsewhere. Searches for LA prevalence and a percentage below 50% found no figure in our copy (page numbers unavailable). (LLM, conf=0.75)

      Experimental — accuracy not yet measured
  • Findingown data

    Four patients (2.5%) had catastrophic APS.

    “The remaining four patients (2.5%) suffered from catastrophic APS.”
    Quote in the paperNot a substantial claim
  • Findingown data

    Major bleeding from oral anticoagulant therapy was infrequent, at 0.8% per patient-year.

    “Major bleeding associated with oral anticoagulant therapy was low (0.8% patient/years).”
    Quote in the paperNot a substantial claim
  • The quote only partly states this claim. 3
  • May combine two claims. 17
  • Classified as probably not a substantial claim. 6

  • The quote only partly states this claim.

    Findingown data

    The study enrolled 160 patients with definite APS and triple positivity for LA, aCL, and ab2GPI antibodies.

    “One hundred and sixty patients were enrolled in this cohort study.”
    • Also stated in: § Results · plain
      “Thus, 160 patients with three positive APS tests were enrolled in this cohort study.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Ten patients died, seven of cardiovascular causes.

    “Ten patients died (seven were cardiovascular deaths).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Pregnancy morbidity was the qualifying event in 11 patients (reported as 6.9% in Results/Table and 9.7% in Abstract).

    “The qualifying event at diagnosis was VTE in 76 cases (47.5%), arterial thromboembolism in 69 cases (43.1%) and pregnancy morbidity in 11 cases (6.9%).”
    • Also stated in: § Abstract · plain
      “The qualifying events at diagnosis were venous thromboembolism (76 cases; 47.5%), arterial thromboembolism (69 cases; 43.1%) and pregnancy morbidity (11 cases; 9.7%).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The present cohort had more men (29% vs 18%) and more primary APS cases (62% vs 53%) than Cervera et al.

    “We had more male patients (29% vs. 18%) and primary APS cases (62% vs. 53%).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [25] source

  • The quote only partly states this claim.

    Findingown data

    Few enrolled patients had obstetric complications alone (9.7% in Discussion; 6.9% in Results/Table).

    “The number of enrolled patients with obstetric complications alone was low (9.7%), highlighting that the majority of female patients with triple positivity in laboratory tests suffer from thromboembolic events [22].”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    There were 10 deaths during follow-up (0.8% patients/years; seven cardiovascular, three non-cardiovascular).

    “There were eight major bleeding events -seven in patients on oral anticoagulants (0.8% patient/years) -and 10 deaths during follow-up (0.8% patients/years; seven were cardiovascular and three were non-cardiovascular deaths).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    At 10 years, cumulative event incidence was 45% for venous, 47% for arterial, and 37% for pregnancy morbidity as qualifying event (P=ns).

    “As shown in Fig. 2, the cumulative incidence of events after 10 years was 45%, 47% and 37% for venous, arterial and pregnancy morbidity as a qualifying event, respectively (P = ns).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Of 160 patients, 55 (34.4%) had a thromboembolic event during follow-up; 25 were VTE and 30 were arterial thromboembolism.

    “Out of the 160 patients, 55 (34.4%) had a thromboembolic event during the follow-up period; 25 were VTE and 30 were arterial thromboembolism.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Of 189 considered patients, 29 were excluded: 11 for unconfirmed laboratory data and 18 for both GPL and MPL aCL titers <40 units.

    “Of the 189 patients considered for this study, 29 were excluded; 11 because the laboratory data were not confirmed in the reference laboratory and 18 for having both GPL and MPL aCL titers of < 40 units.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Subsequent thromboembolism occurred in 36 of 123 anticoagulated patients and 19 of 37 non-anticoagulated patients.

    “Subsequent thromboembolism occurred in 36 (16 VTE and 20 ATE) out of 123 anticoagulated patients [median International normalized ratio (INR) at the time of event 2.3], and in 19 (9 VTE and 10 ATE) out of the 37 non-anticoagulated patients.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    There were eight major bleeding events, seven in patients on oral anticoagulants (0.8% patient/years).

    “There were eight major bleeding events -seven in patients on oral anticoagulants (0.8% patient/years) -and 10 deaths during follow-up (0.8% patients/years; seven were cardiovascular and three were non-cardiovascular deaths).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    123 patients received long-term oral anticoagulants during the entire follow-up, while 37 did not (13 none, 24 aspirin alone).

    “Out of 160 patients, 123 received long-term oral anticoagulant treatment during the entire follow-up period, whereas 37 did not (13 did not take anticoagulants and 24 took aspirin alone).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingown data

    131 (81.9%) patients completed 1-year follow-up, 76 (47.5%) completed 5 years, and 23 (14.4%) completed 10 years.

    “One hundred and thirty-one (81.9%) patients completed the 1year follow-up, 76 (47.5%) completed 5 years and 23 (14.4%) completed 10 years of follow-up.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Mean follow-up was 6.0 ± 4.6 years (range 0.3-20).

    “Mean follow-up was 6.0 (± 4.6) years (range 0.3-20 years).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Many APS clinical studies have mixed laboratory profiles, so their results may be inconsistent.

    “Many clinical studies on APS have included patients with different laboratory profiles, and consequently, the results may lack consistency [14][15][16][17].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [14][15][16][17]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationreasoning

    Since one positive test suffices for APS diagnosis, there is a substantial risk of diagnosing APS in patients with a false-positive test or irrelevant antibodies.

    “As just one positive test is sufficient for APS diagnosis, there is a substantial risk of diagnosing APS in patients with either one false-positive test or with antibodies that recognize a target that is irrelevant to the syndrome.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Oral anticoagulants are recommended after a first VTE to prevent recurrence.

    “Oral anticoagulants are recommended after a first episode of VTE [28] to prevent recurrence [29][30][31][32].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [28] source
    • cites [29][30][31][32]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductown data

    Plasma from each center was retested in a reference laboratory to confirm triple positivity and validate the laboratory diagnosis.

    “To confirm triple positivity for aPL, and to validate the laboratory diagnosis, patient plasma from each center was also tested in a reference laboratory.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The aPL assays lack standardization and have low sensitivity.

    “However, these tests are poorly standardized, which leads to low sensitivity [2][3][4].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [2][3][4]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Study design and conductnone given

    Laboratory data were confirmed in all patients, and tests were repeated in recurrent cases or annually for most patients.

    “Importantly, data were confirmed in all patients and tests were repeated in recurrent cases or each year in the majority of patients.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Thromboembolic events at diagnosis were objectively demonstrated for type and site.

    “Both the type and site of any thromboembolic events at diagnosis were demonstrated objectively.”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Interpretationown data

    Recurrences remain common even with oral anticoagulant use.

    “Recurrence remains frequent despite the use of oral anticoagulants, which significantly reduces the risk of thromboembolism.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Multiple aPL positivity is strongly associated with thromboembolic events and severe pregnancy morbidity.

    “In contrast, multiple positivity shows a marked association with thromboembolic events and severe pregnancy morbidity [8][9][10][11][12][13].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [8][9][10][11][12][13]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationown data

    Oral anticoagulant therapy significantly reduces recurrent thromboembolism, though it may be insufficient in some cases.

    “Oral anticoagulant therapy significantly reduces recurrent thromboembolism, although it might prove insufficient in some cases.”
    Quote in the paperSubstantial claim
24 of 24

  • The paper relies on this without support.

    No prior study has described the characteristics and clinical course of APS in high-risk patients positive for all three recommended aPL tests.

    “To our knowledge, no study has reported the characteristics and clinical course of a homogenous group of APS patients that are positive in all three laboratory diagnostic tests.”
    “The characteristics and the clinical course of antiphospholipid syndrome (APS) in high-risk patients that are positive for all three recommended tests that detect the presence of antiphospholipid (aPL) antibodies have not been described.”

  • The paper relies on this without support.

    This is the first large-scale study to examine the clinical course of a homogeneous cohort of APS patients with full positive laboratory profile.

    “To our knowledge, this is the first large-scale study looking at the clinical course of a homogenous cohort of APS patients with full positive laboratory profile.”
    “which to our knowledge is the first to examine patients that are positive for APS as determined by three separate tests”
2 of 2

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Patients with thrombotic primary antiphospholipid syndrome remain at substantial risk of recurrent thrombotic events despite long-term anticoagulation, with cumulative recurrence rates approaching 20% at 5 years in observational cohorts.

    “Despite long-term anticoagulation with vitamin K antagonists, patients with thrombotic PAPS remain at substantial risk of recurrent thrombotic events, with cumulative recurrence rates approaching 20% at 5 years in observational cohorts [2].”

    From Hydroxychloroquine as an Adjunct Therapy for Secondary Thrombosis Prevention in Primary Antiphospholipid Syndrome: A Systematic Review and Meta-analysis (2026) · cites this paper as [2]

    The Thromboembolic events during the followup period section (page unavailable) reports 36 recurrent events among 123 patients receiving long-term oral anticoagulation, supporting the risk despite treatment. But its 5-year cumulative incidence is 26.1% for the entire high-risk APS cohort, not a rate approaching 20% specifically among anticoagulated patients with thrombotic primary APS. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • In antiphospholipid syndrome patients, thromboembolic event incidence was significantly higher among those not receiving oral anticoagulants (HR 2.4, 95% CI 1.3-4.1, P<0.003).

    “The incidence was significantly higher in patients not taking OAs (HR 2.4, 95% CI 1.3-4.1,P < 0.003) [11].”

    From Antithrombotic effects of hydroxychloroquine in primary antiphospholipid syndrome patients (2013) · cites this paper as [11]

    The ‘Thromboembolic events during the followup period’ section reports significantly higher event incidence without oral anticoagulants and gives the stated HR, confidence interval, and P value. However, the cohort comprised high-risk APS patients positive on all three antiphospholipid antibody tests; the citing sentence does not retain that population restriction. (LLM, conf=0.85)

    Experimental — accuracy not yet measured

  • aPL profiling also involves consideration of antibody titers since higher titers are associated with higher risk.

    “aPL profiling also involves consideration of antibody titers since higher titers are associated with higher risk [7,8,30,31].”

    From Triple-positive antiphospholipid syndrome does not guarantee positivity in each lupus anticoagulant assay (2023) · cites this paper as [7]

    The Discussion (page not provided) says a previous study found a strong correlation between anticardiolipin (aCL) titer and thrombosis, and uses an aCL titer cutoff to select patients at risk. That supports considering aCL titers, but it does not establish the same higher-titer association for aPL antibodies generally. (LLM, conf=0.83)

    Experimental — accuracy not yet measured

  • Triple-positive patients have a high risk for developing a first thrombotic event and recurrence of thrombosis.

    “Patients positive for the combination of LAC, antiβ 2GPI, and anti-CL antibodies,theso-called triple-positive patients, exhibit a high risk for developing a first thrombotic event and recurrence of thrombosis. 8,9”

    From Clinical Relevance of Isolated Lupus Anticoagulant Positivity in Patients with Thrombotic Antiphospholipid Syndrome (2021) · cites this paper as [8]

    The Discussion (page unavailable) says patients positive on all three tests are at higher risk of thrombosis and have a substantial risk of recurrent thromboembolic events. However, this study followed patients already diagnosed with APS and does not establish the risk of a first thrombotic event in triple-positive patients generally. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Patients positive for all three aPLs are identified as individuals at high risk for a first clinical event and for recurrence.

    “andpatientspositiveforallthree aPLs are identified as individuals at high risk for a first clinical event and for recurrence. 8,9”

    From Clinical Relevance of Isolated Lupus Anticoagulant Positivity in Patients with Thrombotic Antiphospholipid Syndrome (2021) · cites this paper as [8]

    The Discussion and Abstract identify triple-positive patients with APS as being at high risk of recurrent thromboembolic events. The study enrolled patients who already had definite APS and a qualifying clinical event, so it does not establish their risk of a first clinical event. Page numbers are not available in the supplied passages. (LLM, conf=0.85)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • Pregnancy morbidity percentage uses a different denominator

    Minor

    The abstract lists 11 pregnancy-morbidity cases as 9.7% of the 160 enrolled patients, but 11/160 is 6.9%. The results and Table 1 report 6.9%.

    Reported 9.7 · recomputed 6.875

  • Other autoimmune disorder percentage in Table 1 does not match the cohort size

    Minor

    Among 160 patients, 34 with other autoimmune disorders would be 21.3%, not 19.3%.

    Reported 19.3 · recomputed 21.25

  • SLE percentage in Table 1 does not match the cohort size

    Minor

    Among 160 patients, 33 with SLE would be 20.6%, not 18.8%.

    Reported 18.8 · recomputed 20.625

  • Arterial risk-factor percentage in Table 1 does not match the cohort size

    Minor

    Among 160 patients, 87 with arterial thrombosis risk factors would be 54.4%, not 49.4%.

    Reported 49.4 · recomputed 54.375

  • Venous risk-factor percentage in Table 1 does not match the cohort size

    Minor

    Among 160 patients, 71 with venous thrombosis risk factors would be 44.4%, not 40.3%.

    Reported 40.3 · recomputed 44.375

5 of 5

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Authors
PENGO, V., RUFFATTI, A., LEGNANI, C., GRESELE, P., BARCELLONA, D., ERBA, N., TESTA, S., MARONGIU, F., BISON, E., DENAS, G., BANZATO, A., PADAYATTIL JOSE, S., & ILICETO, S.
Affiliations
  • University of Padua (IT)
  • University of Bologna (IT)
  • University of Perugia (IT)
  • University of Cagliari (IT)
Corresponding author
PENGO, V.
ORCID
Venue
Journal of Thrombosis and Haemostasis
Publisher
Elsevier BV
Published
2010-02
Volume
8
Issue
2
Pages
237-242
ISSN
1538-7836 (ISSN-L)
DOI
10.1111/j.1538-7836.2009.03674.x
OpenAlex
W2119266650
Cited by
633
References
39
Citations by year
2026: 34 · 2025: 31 · 2024: 39 · 2023: 47 · 2022: 53 · 2021: 45 · 2020: 54 · 2019: 49 · 2018: 41 · 2017: 33 · 2016: 38 · 2015: 35 · 2014: 32 · 2013: 30 · 2012: 32
FWCI
14.40
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Thrombosis and Haemostasis (publishedVersion)
  • PubMed (publishedVersion)
  • UNICA IRIS Institutional Research Information System (University of Cagliari) (submittedVersion)
  • Padua Research Archive (University of Padova) (submittedVersion)
Topics
  • Health Sciences › Medicine › Rheumatology › Systemic Lupus Erythematosus Research
  • Health Sciences › Medicine › Hematology › Blood Coagulation and Thrombosis Mechanisms
  • Health Sciences › Medicine › Internal Medicine › Venous Thromboembolism Diagnosis and Management
Keywords
antiphospholipid syndrome, triple positivity, lupus anticoagulant, anticardiolipin antibodies, anti-beta2-glycoprotein I antibodies, venous thromboembolism, arterial thromboembolism, pregnancy morbidity
MeSH terms
Administration, Oral, Adult, Aged, Anticoagulants, Catastrophic Illness, Female, Hemorrhage, Humans

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