Session Information
Date: Monday, November 6, 2017
Title: Systemic Lupus Erythematosus – Clinical Aspects and Treatment Poster II: Damage and Comorbidities
Session Type: ACR Poster Session B
Session Time: 9:00AM-11:00AM
Background/Purpose:
Studies have indicated that increased body mass index (BMI) is a risk factor for development of Chronic Kidney Disease (CKD). Obesity is a low grade inflammatory state which leads to CKD by lipotoxicity, increased leptin levels, cytokine mediated glomerular injury and fibrosis. Systemic Lupus Erythematosus (SLE) is associated with high leptin levels and dyslipidemia. We studied BMI as a possible predictor for development of lupus nephritis in SLE.
Methods:
We performed a retrospective cross sectional study on a longitudinal lupus cohort. Patients were enrolled from year 1987 to 2015. We compared the demographic information, clinical information, lab results between patients with and without lupus nephritis (Table 1) and between patients with SLE with and without obesity (Table 2). Mean and Inter- quartile ranges were reported for continuous variables, such as age and BMI value. T- test was used to compare patients between the groups. Number and percentages were shown for categorical variables and chi-square test was utilized for comparison.
Results:
Total of 1362 patients with SLE fulfilling revised ACR criteria were included in this analysis; 60.9% were Caucasian and 32.8% African American. 596 had biopsy-proven lupus nephritis however 524 patients were excluded because they had proteinuria before or at cohort entry. Only first available BMI were analyzed: 32.7% were obese (BMI > 30 kg/m2), 27.2% overweight (BMI: 25 -29.9 kg/m2), 37.5% normal (BMI: 18.5 – 24.9 kg/m2) and 2.6% underweight (BMI < 18.5 kg/m2). 39.4% (537) patients were on steroids at first BMI measurement. Results are described in Table 1, 2 and 3.
Conclusion:
Obesity was not associated with the development of lupus nephritis. Obese patients with SLE had lower disease activity as measured by SLEDAI, dsDNA titers and complement levels.
Table 1: SLE patients with vs. without Lupus Nephritis (P < 0.05 in bold)
|
Lupus Nephritis (N = 72) Mean (IQR) / N (%) |
SLE without Lupus Nephritis (N= 1290) Mean (IQR) / N (%) |
P Value |
|
|
Age when BMI are measured |
32.07 (10.85) |
42.53 (20.45) |
<0.0001 |
|
Kidney Biopsy Age |
35.14 (12.05) |
||
|
Ethnicity Caucasian |
20 (27.78%) |
811 (62.87%) |
<0.0001 |
|
Asian |
5 (6.94%) |
36 (2.79%) |
|
|
African American |
42 (58.33%) |
404 (31.32%) |
|
|
Others |
5 (6.94%) |
39 (3.02%) |
|
|
Male |
6 (8.33%) |
76 (5.89%) |
0.4387 |
|
Age when SLE was diagnosed |
27.39 (10.87) |
35.46 (18.38) |
<0.0001 |
|
BMI (continuous) |
26.93 (8.1) |
28.02 (8.68) |
0.1855 |
|
BMI (Categorical) Underweight |
32 (44.44%) |
475 (36.82%) |
0.6242 |
|
Normal Weight |
2 (2.78%) |
38 (2.95%) |
|
|
Overweight |
19 (26.39%) |
372 (28.84%) |
|
|
Obesity |
19 (26.39%) |
405 (31.4%) |
|
|
SLEDAI (continuous score) |
5.04 (4) |
2.13 (4) |
<0.0001 |
|
SLEDAI (>=2 ) |
65 (90.28%) |
690 (53.61%) |
<0.0001 |
|
Urine protein creatinine ratio (> 0.5) |
2 (12.5%) |
4 (0.67%) |
0.0089 |
|
Anti dsDNA (>=10) |
40 (59.7%) |
252 (20.31%) |
<0.0001 |
|
Low C3 (<79) |
37 (53.62%) |
178 (14.19%) |
<0.0001 |
|
Low C4 (<12) |
27 (39.13%) |
146 (11.67%) |
<0.0001 |
|
ESR (>20) |
47 (70.15%) |
576 (47.56%) |
0.0004 |
Table 2: Comparison of disease activity and laboratory data between patients with and without obesity
|
|
SLE patients with obesity (N=692) Mean (IQR)/N(%) |
SLE patients without obesity (N=1512) Mean (IQR)/N(%) |
P Value |
|
SLEDAI (continuous score) |
1.94 (3) |
2.45 (4) |
0.0019 |
|
SLEDAI (>/=2) |
210 (49.41%) |
547 (58.44%) |
0.0022 |
|
Urine protein creatinine ratio (> 0.5) |
1 (0.51%) |
5 (1.19%) |
0.67 |
|
Anti- dsDNA (>/= 10) |
75 (18.43%) |
217 (24.03%) |
0.0261 |
|
Low C3 (<79) |
20 (4.88%) |
195 (21.31%) |
<0.0001 |
|
Low C4 (<12) |
23 (5.62%) |
150 (16.43%) |
<0.0001 |
|
ESR (>20) |
238 (60.41%) |
387 (43.68%( |
<0.0001 |
Table 3: Association between BMI and Lupus Nephritis
|
|
OR |
P Value |
Adjusted OR* |
P Value |
|
BMI (continuous) |
0.98 (0.94,1.01) |
0.2153 |
0.99 (0.95,1.03) |
0.5111 |
|
BMI (Categorical) Underweight |
0.78 (0.18,3.39) |
0.7414 |
0.76 (0.17,3.42) |
0.7171 |
|
Normal Weight |
Reference |
|
Reference |
|
|
Overweight |
0.76 (0.42,1.36) |
0.3525 |
0.86 (0.47,1.60) |
0.6403 |
|
Obesity |
0.70 (0.39,1.25) |
0.2237 |
0.87 (0.47,1.64) |
0.6735 |
*Adjusted for age, sex and ethnicity
To cite this abstract in AMA style:
Chock YP, Danve A, Fu W, Petri M. Increased Body Mass Index May Not be a Risk Factor for the Development of Lupus Nephritis [abstract]. Arthritis Rheumatol. 2017; 69 (suppl 10). https://acrabstracts.org/abstract/increased-body-mass-index-may-not-be-a-risk-factor-for-the-development-of-lupus-nephritis/. Accessed .« Back to 2017 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/increased-body-mass-index-may-not-be-a-risk-factor-for-the-development-of-lupus-nephritis/