Antiphospholipid antibodies predict post-stroke depression after acute ischemic stroke

BACKGROUND

Antiphospholipid activity was reported to be increased in depressive patients, while the impact of antiphospholipid antibodies (aPLs) on post-stroke depression (PSD) is unclear. We aimed to investigate the associations of aPLs, including antiphosphatidylserine (aPS) and anticardiolipin (aCL) antibodies with depression after acute ischemic stroke.

METHODS

aPS and aCL were measured in 497 ischemic stroke patients recruited from 7 of 26 participating hospitals of China Antihypertensive Trial in Acute Ischemic Stroke. 24-item Hamilton Depression Rating Scale was used to evaluate PSD status at 3 months after stroke.

RESULTS

Compared with aPS-negative or aCL-negative, the adjusted odds ratios (ORs) [95% confidence intervals (CIs)] associated with aPS-positive or aCL-positive were 1.77 (1.07-2.92) or 2.06 (1.11-3.80) for risk of PSD. On continuous analyses, per 1-SD increment of aPS and aCL were associated with 29% (OR 1.29, 95% CI 1.06-1.58) and 30% (OR 1.30, 95% CI 1.06-1.60) increased risks for PSD, respectively. Adding aPLs to conventional risk factors models significantly improved risk reclassification for PSD (net reclassification improvement index = 21.87%, P = 0.016 for aPS; net reclassification improvement index = 32.24%, P = 0.0004 for aCL).

LIMITATIONS

aPLs levels were tested only at baseline without serial measurements, and we were unable to detect the association between aPLs changes and PSD.

CONCLUSIONS

Higher aPS and aCL levels in the acute phase of ischemic stroke were associated with increased risk of 3-month PSD, suggesting that aPLs may play an important role in post-stroke depression prediction.

Renal Function Affects Prognostic Role of Antiphosphatidylserine Antibodies for Acute Ischemic Stroke Patients

BACKGROUND

Whether the renal function influences the association between antiphosphatidylserine antibodies (aPS) and prognosis of ischemic stroke remains unclear. We aimed to investigate the prognostic value of aPS after ischemic stroke stratified by renal function status.

METHODS

This prospective study was based on China Antihypertensive Trial in Acute Ischemic Stroke, a randomized clinical trial in 26 hospitals across China from August 2009 to May 2013. A total of 2,874 ischemic stroke patients with blood samples or baseline records of estimated glomerular filtration rate (eGFR) were included in this study. Serum aPS levels were quantitatively measured at baseline, and abnormal renal function in this study was defined as eGFR <90 mL/min per 1.73 m2. The primary outcome was a combination of death and major disability (modified Rankin Scale score ≥3) at 3 months after stroke. Secondary outcomes were death and major disability separately.

RESULTS

The association between aPS and primary outcome was significantly modified by renal function status (p for interaction = 0.02). After adjustment for covariates, increased aPS were significantly associated with the primary outcome in the patients with abnormal renal function (OR 2.09; 95% CI 1.24-3.53; p for trend = 0.006), but not in those with normal renal function (OR 0.92; 95% CI 0.69-1.23; p for trend = 0.59), when 2 extreme tertiles were compared. Furthermore, multiple-adjusted spline regression model showed a linear association between aPS and risk of primary outcome in the patients with abnormal renal function (p for linearity = 0.02) but not in those with normal renal function (p for linearity = 0.71).

CONCLUSIONS

Increased aPS were positively and independently associated with death or major disability after acute ischemic stroke in the patients with abnormal renal function.

Association of anticardiolipin, antiphosphatidylserine, anti-β2 glycoprotein I, and antiphosphatidylcholine autoantibodies with canine immune thrombocytopenia

Background

In humans, the presence of antiphospholipid antibodies (aPL) is frequently found in immune thrombocytopenia. The present study investigated whether aPL and any aPL subtypes are associated with canine thrombocytopenia, in particular, immune-mediated thrombocytopenia (immune thrombocytopenia) that usually manifests with severe thrombocytopenia.

Results

Sera were collected from 64 outpatient dogs with thrombocytopenia (Group I, platelet count 0 – 80 × 10³/uL), and 38 of which having severe thrombocytopenia (platelet count < 30 × 10³/uL) were further divided into subgroups based on the presence of positive antiplatelet antibodies (aPLT) (subgroup I_A, immune thrombocytopenia, n =20) or the absence of aPLT (subgroup I_B, severe thrombocytopenia negative for aPLT, n =18). In addition, sera of 30 outpatient dogs without thrombocytopenia (Group II), and 80 healthy dogs (Group III) were analyzed for comparison. Indirect ELISAs were performed to compare serum levels of aPL subtypes, including anticardiolipin antibodies (aCL), antiphosphatidylserine antibodies (aPS), antiphosphatidylcholine (aPC), and anti-β₂ glycoprotein I antibodies (aβ₂GPI), and antiphosphatidylinositol antibodies (aPI), among different groups or subgroups of dogs. Among outpatient dogs, aCL, being highly prevalent in outpatient dogs with thrombocytopenia (63/64, 98 %), is an important risk factor for thrombocytopenia (with a high relative risk of 8.3), immune thrombocytopenia (relative risk 5.3), or severe thrombocytopenia negative for aPLT (relative risk ∞, odds ratio 19). In addition, aPS is a risk factor for immune thrombocytopenia or severe thrombocytopenia negative for aPLT (moderate relative risks around 2), whereas aPC and aβ₂GPI are risk factors for immune thrombocytopenia (relative risks around 2).

Conclusions

Of all the aPL subtypes tested here, aCL is highly associated with canine thrombocytopenia, including immune thrombocytopenia, severe thrombocytopenia negative for aPLT, and less severe thrombocytopenia. Furthermore, aPS is moderately associated with both canine immune thrombocytopenia and severe thrombocytopenia negative for aPLT, whereas aβ₂GPI, and aPC are moderately relevant to canine immune thrombocytopenia. In contrast, aPI is not significantly associated with canine immune thrombocytopenia.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-016-0727-3) contains supplementary material, which is available to authorized users.