Session Information
Date: Tuesday, October 23, 2018
Title: Systemic Lupus Erythematosus – Clinical Poster III: Treatment
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose: ‘Persistent positivity” has been a part of laboratory criteria for antiphospholipid syndrome classification criteria and requires two positive tests. We investigated the clinical utility of multiple measures of lupus anticoagulant and anticardiolipin antibodies in SLE patients over the course of clinical care.
Methods: We studied 943 SLE patients in a large single-center cohort who were assessed for lupus anticoagulant (by dRVVT) and anticardiolipin (aCL) IgG, IgM and IgA at at least 10 clinic visits. For each patient, we determined the percent of follow-up time positive for antiphospholipid antibodies and assessed the relationship between this percent and lifetime history of thrombosis.
Results: Among those ever positive for antiphospholipid antibodies, the large majority of SLE patients were positive less than 25% of time followed (Table 1).
Table 1. Most SLE Patients are Positive for aCL or dRVVT Less Than 25% of time followed
aPL definition |
Proportion of time during follow-up in which aPL were positive |
||||
0 |
>0-0.25 |
>0.25-0.5 |
>0.5-0.75 |
>0.75 |
|
aCL IgG>=20 |
728 (77%) |
149 (16%) |
33 (4%) |
15 (2%) |
18 (2%) |
aCL IgG>=40 |
856 (91%) |
66 (7%) |
11 (1%) |
5 (1%) |
5 (1%) |
aCL IgM>=20 |
693 (73%) |
185 (20%) |
26 (3%) |
14 (1%) |
25 (3%) |
aCL IgM>=40 |
829 (88%) |
85 (9%) |
14 (1%) |
7 (1%) |
8 (1%) |
aCL IgA>=20 |
861 (91%) |
69 (7%) |
9 (1%) |
0 (0%) |
4 (<1%) |
aCL IgA>=40 |
909 (96%) |
29 (3%) |
2 (<1%) |
1 (<1%) |
2 (<1%) |
dRVVT>45 |
564 (60%) |
273 (29%) |
49 (5%) |
22 (2%) |
35 (4%) |
Any of above |
378 (40%) |
369 (39%) |
90 (10%) |
35 (4%) |
71 (8%) |
For the lupus anticoagulant, there was a progressively increasing association of history of thrombosis with greater proportion of time positive (Table 2). For anticardiolipin antibodies or lupus anticoagulant, even those with relatively infrequent positive measures had a greater likelihood of a history of thrombosis than those who were never positive.
Table 2: Associations of aCL and dRVVT with Thrombosis.
aPL Definition |
Proportion of time with aPL |
Any Thrombosis |
|||
N |
Number (%) with Thrombosis |
RR1 (95% CI) |
P-value |
||
aCL IgG>20 |
0 |
728 |
138 (19%) |
1.0 (Ref) |
|
>0-0.25 |
149 |
46 (31%) |
1.7 (1.2, 2.3) |
0.0034 |
|
>0.25-0.5 |
33 |
9 (27%) |
1.5 (0.9, 2.5)2 |
0.13 |
|
>0.5-.75 |
15 |
1 (7%) |
|||
>0.75 |
18 |
7 (39%) |
|||
aCL IgG>40 |
0 |
856 |
175 (20%) |
1.0 (Ref) |
|
>0-0.25 |
66 |
20 (30%) |
1.5 (0.9, 2.3) |
0.11 |
|
>0.25-0.5 |
11 |
2 (18%) |
1.8 (0.8, 4.0)2 |
0.16 |
|
>0.5-.75 |
5 |
2 (40%) |
|||
>0.75 |
5 |
2 (40%) |
|||
aCL IgM>20 |
0 |
693 |
138 (20%) |
1.0 (Ref) |
|
>0-0.25 |
185 |
41 (22%) |
1.2 (0.9, 1.8) |
0.24 |
|
>0.25-0.5 |
26 |
8 (31%) |
1.7 (1.1, 2.7)2 |
0.020 |
|
>0.5-.75 |
14 |
3 (21%) |
|||
>0.75 |
25 |
11 (44%) |
|||
aCL IgM>40 |
0 |
829 |
166 (20%) |
1.0 (Ref) |
|
>0-0.25 |
85 |
24 (28%) |
1.4 (0.9, 2.2) |
0.099 |
|
>0.25-0.5 |
14 |
4 (29%) |
2.2 (1.2, 4.0)2 |
0.012 |
|
>0.5-.75 |
7 |
3 (43%) |
|||
>0.75 |
8 |
4 (50%) |
|||
aCL IgA>20 |
0 |
861 |
177 (21%) |
1.0 (Ref) |
|
>0-0.25 |
69 |
18 (26%) |
1.1 (0.7, 1.9) |
0.59 |
|
>0.25-0.5 |
9 |
4 (44%) |
2.1 (0.9, 4.7)2 |
0.079 |
|
>0.5-.75 |
0 |
||||
>0.75 |
4 |
2 (50%) |
|||
aCL IgA>40 |
0 |
909 |
190 (21%) |
1.0 (Ref) |
|
>0-0.25 |
29 |
9 (31%) |
1.3 (0.7, 2.5) |
0.45 |
|
>0.25-0.5 |
2 |
1 (50%) |
1.7 (0.4, 6.8)2 |
0.46 |
|
>0.5-.75 |
1 |
0 (0%) |
|||
>0.75 |
2 |
1 (50%) |
|||
dRVVT>45 |
0 |
564 |
91 (16%) |
1.0 (Ref) |
|
>0-0.25 |
273 |
68 (25%) |
1.5 (1.1, 2.0) |
0.018 |
|
>0.25-0.5 |
49 |
19 (39%) |
2.7 (1.6, 4.43) |
0.0001 |
|
>0.5-.75 |
22 |
8 (36%) |
2.2 (1.1, 4.5) |
0.033 |
|
>0.75 |
35 |
15 (43%) |
3.4 (2.0, 5.9) |
<0.0001 |
|
Any of the above |
0 |
378 |
60 (16%) |
1.0 (Ref) |
|
>0-0.25 |
369 |
81 (22%) |
1.3 (1.0, 1.9) |
0.095 |
|
>0.25-0.5 |
90 |
25 (28%) |
1.8 (1.1, 2.8) |
0.016 |
|
>0.5-.75 |
35 |
8 (23%) |
1.5 (0.7, 3.1) |
0.31 |
|
>0.75 |
71 |
27 (38%) |
2.6 (1.6, 4.1) |
<0.0001 |
1 Based on a Cox Model. 2 RR and p-value are for >0.25-0.5, >0.5-0.75, and >0.75 groups combined compared to Reference.
Conclusion: In SLE, antiphospholipid antibody positivity tends to be at a minority of visits. Yet, even those with sporadic positive findings are at increased risk of thrombosis. This contrasts with the natural history of primary antiphospholipid antibodies/syndrome. These data strongly support prophylactic therapy in those who are sporadically positive.
To cite this abstract in AMA style:
Petri M, Avci M, Magder LS. Longitudinal Analysis of Persistent Positivity of Antiphospholipid Antibodies in Systemic Lupus Erythematosus [abstract]. Arthritis Rheumatol. 2018; 70 (suppl 9). https://acrabstracts.org/abstract/longitudinal-analysis-of-persistent-positivity-of-antiphospholipid-antibodies-in-systemic-lupus-erythematosus/. Accessed .« Back to 2018 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/longitudinal-analysis-of-persistent-positivity-of-antiphospholipid-antibodies-in-systemic-lupus-erythematosus/