Session Information
Session Type: ACR Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose:
The course of systemic lupus erythematosus (SLE) varies with periods of quiescence punctuated by flares. Predicting exacerbations allows clinicians to select patients who need closer monitoring and guides therapy. However, such data are limited, especially in Asians. We aim to identify the clinical predictors of flares in patients with stable SLE.
Methods:
We enrolled patients ≥ 21 years old with SLE into a prospective observational study. All patients fulfilled either the 1997 ACR Criteria or the 2012 SLICC Classification Criteria. We collected demographic and clinical data by examination and chart review at baseline and three-monthly intervals for up to 5 years. We defined stable disease as SLE Disease Activity Index-2K (SLEDAI-2K) of ≤ 4 and flares using the SLE Flare Index. We determined the predictors of flare in patients with stable disease using Cox proportional hazards. We included variables with P<0.2 on univariate analysis in the multivariate model. Results are expressed as hazard ratios (HR) and 95% confidence intervals (CI).
Results:
We followed 210 patients for a median (IQR) of 31.5 months (24.1, 36.3). The median age (IQR) was 30.6 years (22.3, 42.5) and 91.4% were female. The majority were Chinese (70.5%). The median (IQR) disease duration from diagnosis was 9.96 years (4.5, 15.5). The median baseline SLEDAI-2K was 2 (2, 6) and the baseline SLICC damage score was 0 (0, 2). 152 (72.4%) patients had stable disease at baseline. Table 1 shows the baseline demographic and disease variables. In 5729 patient-months of follow-up, 109 (51.9%) patients had a flare. Median time to first flare was longer in patients with stable disease (10.7 vs. 8.3 months). Figure 1 shows the Kaplan-Meier Failure Curve of the risk of first flare in patients with stable versus active SLE. In the multivariate model of patients with stable SLE, younger age, longer disease duration, thrombocytopenia, hypocomplementemia and higher baseline prednisolone dose predicted flares. Table 2 shows the results of the univariate and multivariate analysis.
Conclusion:
Rheumatologists should closely monitor patients with stable SLE who are (i) younger; (ii) have longer disease duration; (iii) thrombocytopenic; (iv) hypocomplementemic; (iv) requiring higher baseline prednisolone doses; as these patients are more likely to develop flares.
Table 1. Baseline Demographic and Disease Variables |
||
|
Baseline Active Disease (SELDAI-2k >4) |
Baseline Stable Disease (SLEDAI-2k ≤4) |
Number |
58 |
152 |
Demographic Variables |
||
Median Age of Onset (IQR) |
29.2 (22.4- 37.6) |
31.3 (22.0- 43.9) |
Females (%) |
86.2% |
93.4% |
Ethnicity (%) |
||
Chinese |
65.52 |
72.37 |
Malays |
17.24 |
13.16 |
Indians |
8.62 |
8.55 |
Others |
8.62 |
5.92 |
Education Level (%) |
||
Primary |
25.86 |
27.63 |
Secondary |
34.48 |
33.55 |
Tertiary |
39.66 |
38.82 |
Positive Family History (%) |
5.17 |
11.18 |
Current Smokers (%) |
3.45 |
2.63 |
Disease Variables |
||
|
Median (IQR) |
Median (IQR) |
CRP (mg/L) |
20 (5-29) |
5 (2-21) |
ESR (mm/hr) |
36 (18-63) |
22.5 (16-36) |
Complement 3 (mg/dL) |
71.5 (58-91.5) |
87 (75-100) |
Complement 4 (mg/dL) |
15.5 (9.5-25) |
19 (14-25.5) |
Hemoglobin (109/L) |
12.2 (11.3-13.4) |
11.7 (10.4- 13.1) |
Total White Cell (109/L) |
6.58 (4.74- 8.47) |
5.44 (4.31-7.01) |
Lymphocyte (109/L) |
1.06 (0.7-1.43) |
1.25 (0.88-1.89) |
Platelet (109/L) |
247 (186-287) |
230 (194-279) |
Estimated Glomerular Filtration Rate (ml/min) |
76 (60- 116) |
94 (60-114) |
Albumin (g/L) |
37 (33-41) |
40 (37-42) |
Table 2. Predictors of Flare by Cox Proportional Hazards |
||||||
Variable |
|
Univariate Analysis |
Multivariate Analysis |
|||
Median values (IQR) |
Hazard Ratio (CI) |
P value |
Hazard Ratio (CI) |
P value |
||
Young age (Lowest tertile vs. top two tertiles in years) |
31.9 (25.7, 34.5) vs 50.0 (46.6, 54.1) |
2.03 (1.28-3.21) |
0.003 |
3.08 (1.72-5.48) |
<0.001 |
|
Females (vs. males) |
N.A. |
1.15 (0.42-3.15) |
0.79 |
N.A. |
||
Current smoker (vs. ex-smoker or non-smoker) |
N.A. |
2.29 (0.72-7.33) |
0.16 |
6.67 (0.83- 53.42) |
0.07 |
|
Malays (vs. Chinese) |
N.A. |
0.73 (0.35-1.53) |
0.41 |
N.A. |
||
Indians (vs. Chinese) |
N.A. |
0.72 (0.31-1.67) |
0.44 |
N.A. |
||
Other Ethnicities (vs. Chinese) |
N.A. |
1.04 (0.38-2.87) |
0.94 |
N.A. |
||
Early disease (Lowest tertile of disease duration vs. top two tertiles in years) |
2.4 (1.12, 4.53) vs 14.6 (11.6, 18.3) |
0.61 (0.36- 1.04) |
0.07 |
0.41 (0.21-0.80) |
0.01 |
|
Leukopenia (<3.84 x109/L) vs. normal white cell count |
2.23 (1.81, 2.72) vs 5.73 (4.52, 7.54) |
0.91 (0.22-3.71) |
0.89 |
N.A. |
||
Lymphopenia (<0.91 x109/L) vs. normal lymphocyte count |
0.70 (0.54, 0.88) vs 1.6 (1.25, 1.98) |
1.09 (0.69-1.75) |
0.71 |
N.A. |
||
Thrombocytopenia (≤100 x 109/L) vs. normal platelet count |
70 (63, 84) vs 246 (204, 283) |
3.22 (1.16-8.89) |
0.02 |
5.01 (1.32-18.99) |
0.02 |
|
Low complement 3 or complement 4 vs. normal complement (mg/dL) |
C3: 56 (48, 62) vs 80 (89, 102) C4: 9 (8, 13) vs 20 (15, 27) |
2.38 (1.34-4.21)
|
0.003 |
3.35 (1.54-7.30) |
0.002 |
|
Positive anti-dsDNA vs. negative anti-dsDNA |
N.A. |
1.20 (0.93- 1.56)
|
0.16 |
1.04 (0.79-1.38) |
0.77 |
|
ESR (Highest tertile vs. lowest tertile in mm/hr) |
60 (43, 70) vs 14 (12, 16) |
0.66 (0.27-1.57)
|
0.35 |
N.A. |
||
Renal involvement vs no renal involvement |
N.A. |
1.43 (0.91-2.22) |
0.12 |
1.42 (0.80-2.48) |
0.23 |
|
High prednisolone dose (Highest tertile vs lowest two tertiles in mg/day)
|
7.5 (5, 10) vs 1.5 (1.25, 2.25) |
2.78 (1.62- 4.78) |
<0.001 |
2.39 (1.28-4.46) |
0.01 |
|
Presence of SLICC Damage vs. no SLICC Damage |
2 (1, 4) vs 0 |
0.87 (0.55-1.36) |
0.54 |
N.A. |
||
Current hydroxychloroquine use vs not on hydroxychloroquine |
N.A. |
1.11 (0.51-2.42) |
0.79 |
N.A. |
||
To cite this abstract in AMA style:
Cho J, Lahiri M, Teoh LK, Dhanasekaran P, Cheung PMP, Lateef A. Predicting Flares in Patients with Stable Systemic Lupus Erythematosus [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/predicting-flares-in-patients-with-stable-systemic-lupus-erythematosus/. Accessed .« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/predicting-flares-in-patients-with-stable-systemic-lupus-erythematosus/