Development of Clinical Decision Models for the Prediction of Systemic Lupus Erythematosus and Sjogren's Syndrome Overlap

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Article
Development of Clinical Decision Models for the Prediction of
Systemic Lupus Erythematosus and Sjogren’s Syndrome Overlap
Yan Han, Ziyi Jin, Ling Ma, Dandan Wang, Yun Zhu, Shanshan Chen, Bingzhu Hua, Hong Wang
and Xuebing Feng *

                                         Department of Rheumatology and Immunology, The Affiliated Drum Tower Hospital of Nanjing University
                                         Medical School, Nanjing 210008, China
                                         * Correspondence: fengxuebing@hotmail.com

                                         Abstract: Objective: To explore the clinical features of patients with systemic lupus erythematosus
                                         and Sjögren’s syndrome overlap (SLE-SS) compared to concurrent SLE or primary SS (pSS) patients,
                                         we utilized a predictive machine learning-based tool to study SLE-SS. Methods: This study included
                                         SLE, pSS, and SLE-SS patients hospitalized at Nanjing Drum Hospital from December 2018 to
                                         December 2020. To compare SLE versus SLE-SS patients, the patients were randomly assigned to
                                         discovery cohorts or validation cohorts by a computer program at a ratio of 7:3. To compare SS
                                         versus SLE-SS patients, computer programs were used to randomly assign patients to the discovery
                                         cohort or the validation cohort at a ratio of 7:3. In the discovery cohort, the best predictive features
                                         were determined using a least absolute shrinkage and selection operator (LASSO) logistic regression
                                         model among the candidate clinical and laboratory parameters. Based on these factors, the SLE-SS
                                         prediction tools were constructed and visualized as a nomogram. The results were validated in
                                         a validation cohort, and AUC, calibration plots, and decision curve analysis were used to assess
                                         the discrimination, calibration, and clinical utility of the predictive models. Results: This study of
                                         SLE versus SLE-SS included 290 patients, divided into a discovery cohort (n = 203) and a validation
                                         cohort (n = 87). The five best characteristics were selected by LASSO logistic regression in the
                                         discovery cohort of SLE versus SLE-SS and were used to construct the predictive tool, including
Citation: Han, Y.; Jin, Z.; Ma, L.;      dry mouth, dry eye, anti-Ro52 positive, anti-SSB positive, and RF positive. This study of SS versus
Wang, D.; Zhu, Y.; Chen, S.; Hua, B.;    SLE-SS included 266 patients, divided into a discovery cohort (n = 187) and a validation cohort
Wang, H.; Feng, X. Development of
                                         (n = 79). In the discovery cohort of SS versus SLE-SS, by using LASSO logistic regression, the eleven
Clinical Decision Models for the
                                         best features were selected to build the predictive tool, which included age at diagnosis (years),
Prediction of Systemic Lupus
                                         fever, dry mouth, photosensitivity, skin lesions, arthritis, proteinuria, hematuria, hypoalbuminemia,
Erythematosus and Sjogren’s
                                         anti-dsDNA positive, and anti-Sm positive. The prediction model showed good discrimination,
Syndrome Overlap. J. Clin. Med. 2023,
12, 535. https://doi.org/10.3390/
                                         good calibration, and fair clinical usefulness in the discovery cohort. The results were validated in
jcm12020535                              a validation cohort of patients. Conclusion: The models are simple and accessible predictors, with
                                         good discrimination and calibration, and can be used as a routine tool to screen for SLE-SS.
Academic Editor: Chang-Hee Suh

Received: 13 December 2022               Keywords: systemic lupus erythematosus; Sjögren’s syndrome; overlap; prediction model
Revised: 31 December 2022
Accepted: 4 January 2023
Published: 9 January 2023
                                         1. Introduction
                                               Systemic lupus erythematosus (SLE) is a typical autoimmune connective tissue disease
                                         that can clinically accumulate in multiple organs throughout the body and is more prevalent
Copyright: © 2023 by the authors.
                                         in women of reproductive age [1,2]. Sjögren’s syndrome (SS) is a chronic inflammatory
Licensee MDPI, Basel, Switzerland.
                                         autoimmune disease mainly involving the exocrine glands. SS is clinically manifested
This article is an open access article
distributed under the terms and
                                         as dryness of the mouth and eyes, but extra glandular organs may also be involved,
conditions of the Creative Commons
                                         either independently or in combination with other connective tissue diseases, including
Attribution (CC BY) license (https://    rheumatoid arthritis and systemic lupus erythematosus [3–5]. These two diseases often
creativecommons.org/licenses/by/         coexist in the same individual, which may affect the proper diagnosis and prognosis for
4.0/).                                   these patients. The association of SLE and SS was first described in 1959, and SLE with SS

J. Clin. Med. 2023, 12, 535. https://doi.org/10.3390/jcm12020535                                             https://www.mdpi.com/journal/jcm
J. Clin. Med. 2023, 12, 535                                                                                             2 of 10

                              is considered a distinct subtype of SLE [6]. In recent years, the number of patients with SLE
                              and SS overlap has gradually increased, and studies have shown that 8.3–19.0% of SLE
                              patients also have SS [7]. Another study in China even showed that 24 out of 55 SLE cases
                              (43.6%) had secondary SS [8].
                                   In addition to finding that the prognosis of patients with SLE-SS overlap is different
                              from that of patients with a single disease, previous studies have also revealed that these
                              patients have unique clinical characteristics [9–11]. Unfortunately, the conclusions in
                              different reports are varied, and more than 10 types of clinical manifestations are involved,
                              which is difficult to use for routine clinical implementation. Therefore, it is necessary to
                              develop a practical and reliable screening technique to help identify patients with SLE-SS
                              overlap early to improve their long-term outcome.
                                   In this study, we retrospectively analyzed clinical data related to patients with SLE, SS,
                              and SLE-SS. The risk factors affecting patients with SLE or SS in SLE-SS were extracted,
                              and a decision model for predicting patients with SLE or SS versus SLE-SS was constructed.
                              This model may provide a simple and effective tool for identifying patients with SLE-SS.

                              2. Materials and Methods
                              2.1. Patients and Controls
                                   Data were retrospectively collected from 477 patients with SLE (n = 211), pSS (n= 187),
                              and SLE-SS (n = 79) between December 2018 and December 2020 from the Department
                              of Rheumatology and Immunology of Nanjing Drum Tower Hospital. The diagnosis of
                              SLE was given according to the 1997 American College of Rheumatology (ACR) revised
                              criteria for the classification of systemic lupus erythematosus [12], and the diagnosis of
                              pSS was based on the 2002 American-European Consensus group criteria [13]. SLE-SS
                              is defined as meeting the diagnostic criteria for both SLE and secondary SS, excluding
                              patients with lymphoma, nodal disease, hepatitis virus infection, AIDS, radiation therapy,
                              and anti-acetylcholine drugs.

                              2.2. Data Collection
                                   Data on demographic characteristics and clinical and laboratory findings were col-
                              lected retrospectively. The clinical features assessed included fever, alopecia, asthenia, dry
                              mouth, dry eye, photosensitivity, skin lesions, oral ulcer, Raynaud phenomenon, cavities,
                              epistaxis, arthritis, interstitial lung disease, pulmonary arterial hypertension, and vasculitis.
                              Laboratory findings included proteinuria, hematuria, anemia, leukocytopenia, thrombo-
                              cytopenia, hypoalbuminemia, increased blood urea nitrogen, increased serum creatinine,
                              increased erythrocyte sedimentation rate (ESR), increased C-reactive protein, hypocomple-
                              mentemia, ANA, anti-dsDNA antibody, anti-SSA antibody, anti-Ro52 antibody, anti-SSB
                              antibody, anti-Sm antibody, anti-RNP antibody, anti-cardiolipin antibody, rheumatoid fac-
                              tor (RF)-positive, and IgG elevation. Normal values for the laboratory tests were as follows:
                              hemoglobin ≥ 110 g/L (female) or 120 g/L (male); platelets 100–300 × 109 /L; leukocytes
                              4–10 × 109 /L; serum albumin ≥ 35 g/L; blood urea nitrogen (BUN) ≤ 7.5 mmol/L; serum
                              creatinine ≤ 133 µmol/L; erythrocyte sedimentation rate (ESR) ≤ 20 (female) or ≤15 mm/h
                              (male); CRP ≤ 8 mg/L; complement C3 ≥ 0.8 g/L or C4 ≥ 0.2 g/L; ANA-negative
                              (
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                                    For SLE versus SLE-SS, a total of 290 patients were randomly assigned to the discovery
                              cohort (n = 203) or the validation cohort (n = 87) using a computer program at a ratio of
                              7:3. Similarly, for SS versus SLE-SS, a total of 266 patients were randomly assigned to the
                              discovery cohort (n = 187) or the validation cohort (n = 79) using a computer program at
                              a ratio of 7:3. For the training group, the sample size followed the 10-fold criterion, that
                              is, each prediction variable needs at least 10 observations to produce a reasonable and
                              stable estimate [14,15]. In this study, 5 predictive variables were selected as the final model,
                              requiring at least 50 observations and a sample size of at least 200 for the training group
                              based on a 25% incidence. PASS 15 software (NCSS, LLC, Kaysville, Utah) was used to
                              calculate the sample size of the verification group [16]. The minimum number of positive
                              events was 10, the minimum number of negative events was 50, and the minimum sample
                              size of the verification group was 60. A sufficient sample size is included in this study.
                              We developed prediction tools using the discovery cohorts. A least absolute shrinkage
                              and selection operator (LASSO) logistic regression model and 10-fold cross-validation
                              were applied to select the best predictive features among the clinical characteristics and
                              laboratory parameters in the discovery cohort that were statistically different between SLE
                              and SLE-SS or SS and SLE-SS. The performance of the predictive tool was evaluated for
                              discrimination, calibration, and clinical usefulness. To assess the discrimination of the
                              predictive model, the discriminatory ability was measured using the area under the receiver
                              operating characteristic (AUC) curve. Calibration curves were then plotted to evaluate the
                              calibration effect of the SLE-SS prediction models. Decision curve analysis was used by
                              quantifying the net benefits to determine the clinical utility of the SLE-SS predictive models.
                                    All data analyses used R software (version 4.0.3). In R software, Packages (“rms”) and
                              (“rmda”) were operated. All tests were two-sided, and a p-value < 0.05 was considered
                              statistically significant.

                              3. Results
                              3.1. Patient Characteristics
                                   For SLE versus SLE-SS, a total of 290 patients were included in this study, and a random
                              sample at a ratio of 7:3 was divided into discovery (n = 203) and validation groups (n = 87).
                              Regarding SS versus SLE-SS, a total of 266 patients were included in this study and were
                              randomized in a 7:3 ratio to the discovery (n = 187) and validation groups (n = 79). A flow
                              chart is shown in Figure 1. Table S1 summarizes the clinical characteristics and laboratory
                              parameters of the discovery and validation groups. The characteristics of the two groups
                              of patients were comparable. We also summarize the clinical characteristics and laboratory
                              parameters of SLE, SS, and SLE-SS in the discovery and validation cohorts in Tables S2 and S3.

                              3.2. Development of the Prediction Tool for SLE or SLE-SS
                                   The 11 candidate clinical and laboratory indicators that were statistically different
                              between SLE-SS and SLE were reduced to the five most useful predictive markers by using
                              LASSO logistic regression (Figure 2A,B). These characteristics included dry mouth, dry eye,
                              anti-Ro52 positive, anti-SSB positive, and RF positive. The results of the logistic regression
                              analysis for SLE versus SLE-SS are given in Table 1. We constructed prediction tools based
                              on these factors for SLE in SLE-SS and visualized them as nomograms (Figure 3A).
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     J. Clin. Med. 2023, 12, 535                                                                                                        4 of 10

                                    Figure 1. Flowchart for constructing the SLE or SS in the SLE-SS prediction tool.

                                    Table 1. Risk factors for patients with SLE or SS to develop SLE-SS.

                                                                                                                Prediction Model
                                                         Intercept
                                   Figure 1. Flowchart for         and Variable
                                                           constructing  the SLE or SS in the SLE-SS prediction tool.
                                                                                        β       Odds Ratio (95% CI)                  p-Value
                                                                    Dry mouth                    1.83            6.24(2.00–19.80)     0.00
                                   3.2. Development of the Prediction
                                                               Dry eye
                                                                       Tool for SLE or  SLE-SS 3.42(0.95–12.89)
                                                                                     1.23                               0.06
                                              11 candidateAnti-Ro52
                                         Thedevelop
                                        SLE                 clinicalpositive
                                                                      and laboratory 0.96
                                                                                        indicators2.60(1.13–6.18)       0.03 different
                                                                                                    that were statistically
                                          SLE-SS          Anti-SSB positive          1.02         2.77(1.12–6.91)       0.03
                                   between SLE-SS and SLE were reduced to the five most useful predictive markers by using
                                                             RF positive             1.84        6.29(2.37–17.32)       0.00
                                   LASSO logistic regression     (Figure
                                                       Age at diagnosis    2A,B). These
                                                                        (years)      −0.02characteristics  included dry0.28
                                                                                                  0.98(0.94–1.02)         mouth, dry
                                   eye, anti-Ro52 positive, anti-SSB
                                                                Fever
                                                                         positive, and  RF positive.
                                                                                     2.24
                                                                                                       The results of the
                                                                                                 9.40(2.17–48.81)
                                                                                                                           logistic re-
                                                                                                                        0.00
                                   gression analysis for SLEDryversus
                                                                  mouth SLE-SS   are given
                                                                                     −3.02  in Table   1. We   constructed
                                                                                                 0.049(0.01–0.31)       0.00prediction
                                                           Photosensitivity          3.22       24.94(2.72–363.01)
                                   tools based on these factors for SLE in SLE-SS and visualized them as nomograms      0.01 (Figure
                                                             Skin lesions            3.64       38.04(6.25–341.38)      0.00
                                   3A).
                                        SS develop                  Arthritis                    0.75             2.12(0.53–8.82)     0.29
                                          SLE-SS                   Proteinuria                   1.07            2.91(0.68–13.06)     0.15
                                                                   Hematuria                     2.54            12.0(2.62–78.66)     0.00
                                                               Hypoalbuminemia                   2.89           17.95(4.07–106.35)    0.00
                                                              Anti-dsDNA positive                2.46            11.75(2.82–61.23)    0.00
                                                                Anti-Sm positive                 0.02             0.98(0.12–8.81)     0.99
                                    β is the regression coefficient. OR: Odds ratio; CI: Confidence interval.
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     J. Clin. Med. 2023, 12, 535                                                                                                          5 of 10

                                   Figure
                                     Figure2.2.Clinical
                                                Clinicaland
                                                         and laboratory    parameterselection
                                                              laboratory parameter      selection   using
                                                                                                using   the the LASSO
                                                                                                             LASSO       binary
                                                                                                                    binary         logistic
                                                                                                                            logistic         regression
                                                                                                                                      regression
                                   model.
                                     model.(A,B)
                                              (A,B)Results
                                                     Resultsfor
                                                             forthe
                                                                 the11
                                                                     11variables   includedin
                                                                        variables included    inthe
                                                                                                  theLASSO
                                                                                                      LASSOregression
                                                                                                                regression   associated
                                                                                                                         associated    withwith
                                                                                                                                             SLESLE in
                                   SLE-SS  and the
                                     in SLE-SS   andcorresponding     coefficients
                                                      the corresponding             forfor
                                                                          coefficients   thethe
                                                                                             corresponding
                                                                                                correspondingvariables
                                                                                                                 variablesatatdifferent
                                                                                                                               different values.
                                                                                                                                         values. (C,D)
                                   Results
                                     (C,D) for  the for
                                            Results  17 variables   included
                                                        the 17 variables       in theinLASSO
                                                                          included      the LASSOregression   associated
                                                                                                     regression           with
                                                                                                                 associated  withSS SSand
                                                                                                                                       and their
                                                                                                                                            their corre-
                                   sponding    coefficients  for the  corresponding      variables   at  different values   of  coefficients.
                                     corresponding coefficients for the corresponding variables at different values of coefficients. LASSO,    LASSO,
                                   minimum     absolute  shrinkage,   and   selection  operators.
                                     minimum absolute shrinkage, and selection operators.

                                   Table 1.Similarly,
                                            Risk factors for patients
                                                      as shown        with SLE
                                                                 in Figure      orLASSO
                                                                            2C,D, SS to develop
                                                                                          logisticSLE-SS.
                                                                                                   regression was used to reduce
                                     the 17 candidate laboratory indicators that were statistically different between SLE-SS and
                                     SS to the 11 most useful   predictive markers                      Prediction
                                                                                    including age at diagnosis        Model
                                                                                                                  (years), fever, dry
                                                              Intercept  and   Variable
                                                                                             β
                                     mouth, photosensitivity, skin lesions, arthritis, proteinuria,Odds    Ratiohypoalbuminemia,
                                                                                                    hematuria,     (95% CI) p-Value
                                     anti-dsDNA positive, Dryand anti-Sm
                                                                  mouth positive. The results
                                                                                           1.83of the logistic regression analysis 0.00
                                                                                                       6.24(2.00–19.80)            of
                                     SS and SLE-SS are shown      in
                                                            Dry eye  Table 1. Based on these factors,
                                                                                           1.23        we constructed
                                                                                                       3.42(0.95–12.89) a prediction
                                                                                                                                   0.06
                                     tool for SS in SLE-SS and visualized it as a nomogram (Figure 3B).
                                                      Anti-Ro52 positive                           0.96        2.60(1.13–6.18)               0.03
                                   SLE develop SLE-SS
                                                      Anti-SSB positive                           1.02         2.77(1.12–6.91)               0.03
                                                      RF positive                                 1.84        6.29(2.37–17.32)               0.00
                                                      Age at diagnosis (years)                    −0.02       0.98(0.94–1.02)                0.28
                                                      Fever                                       2.24        9.40(2.17–48.81)               0.00
                                                      Dry mouth                                   −3.02       0.049(0.01–0.31)               0.00
                                    SS develop SLE-SS
                                                      Photosensitivity                            3.22       24.94(2.72–363.01)              0.01
                                                      Skin lesions                                3.64       38.04(6.25–341.38)              0.00
Proteinuria                    1.07       2.91(0.68–13.06)          0.15
                                                       Hematuria                      2.54       12.0(2.62–78.66)          0.00
                                                       Hypoalbuminemia                2.89     17.95(4.07–106.35)          0.00
                                                       Anti-dsDNA positive            2.46      11.75(2.82–61.23)          0.00
J. Clin. Med. 2023, 12, 535                            Anti-Sm positive               0.02        0.98(0.12–8.81)          0.996 of 10
                              β is the regression coefficient. OR: Odds ratio; CI: Confidence interval.

                                         Nomogram prediction
                               Figure3.3.Nomogram
                              Figure               prediction of
                                                              of SLE-SS.
                                                                 SLE-SS. (A)
                                                                          (A)The
                                                                              Theprediction
                                                                                   predictionmodel
                                                                                              modelofofSLE
                                                                                                        SLEinin
                                                                                                              SLE-SS was
                                                                                                                SLE-SS   visualized
                                                                                                                       was  visual-
                               as a nomogram. (B) The prediction  model  of SS in SLE-SS was  visualized as  a nomogram.
                              ized as a nomogram. (B) The prediction model of SS in SLE-SS was visualized as a nomogram.

                               3.3. Model Performance Assessment
                                    Similarly, as shown in Figure 2C,D, LASSO logistic regression was used to reduce
                              the 17The   AUC oflaboratory
                                      candidate     SLE versus   SLE-SS and
                                                               indicators thatSS versus
                                                                               were       SLE-SS was
                                                                                      statistically      0.880 between
                                                                                                    different  (95% CI: SLE-SS
                                                                                                                         0.826–0.934)
                                                                                                                                 and
                               and  0.970  (95%   CI: 0.946–0.995),  respectively,  indicating  that  the  predictive
                              SS to the 11 most useful predictive markers including age at diagnosis (years), fever,   tool had good
                                                                                                                                 dry
                               discrimination
                              mouth,             in the discovery
                                       photosensitivity,            cohort
                                                           skin lesions,    (Figureproteinuria,
                                                                         arthritis,   4A,D). In this   study, the
                                                                                                   hematuria,     calibration curves
                                                                                                                hypoalbuminemia,
                               for both SLEpositive,
                              anti-dsDNA      versus SLE-SS     and SS positive.
                                                        and anti-Sm    versus SLE-SS    also showed
                                                                                 The results            good nomogram
                                                                                               of the logistic  regressionagreement
                                                                                                                             analysis
                               in the  discovery   cohorts  (Figure  4C,F). The  DCA    of the SLE   versus
                              of SS and SLE-SS are shown in Table 1. Based on these factors, we constructed   SLE-SS  prediction  tool
                                                                                                                        a prediction
                               is presented   in Figure   5A. The  decision  curve   showed    that
                              tool for SS in SLE-SS and visualized it as a nomogram (Figure 3B).    if the  threshold  probability  of
                               a patient and a doctor was >5 and
ment in the discovery cohorts (Figure 4C,F). The DCA of the SLE versus SLE-SS prediction
                                                tool is presented in Figure 5A. The decision curve showed that if the threshold probability
                                                of a patient and a doctor was >5 and
J. Clin. Med. 2023, 12, 535                                                                                                  8 of 10

                              4. Discussion
                                    Previous studies have explored potential risk factors for SLE or SS in SLE-SS, including
                              demographics, clinical characteristics, and laboratory parameters [10,11,17,18]. However,
                              no studies have investigated models that incorporate multiple laboratory findings in
                              clinical decision making. In this study, the SLE-SS overlapping disease prediction models
                              were established using the minimum absolute contraction and selection operator (LASSO)
                              logistic regression model between the candidate clinical features and laboratory parameters
                              and were visualized as nomograms to help predict the risk of SLE or SS in SLE-SS.
                                    The clinical features of SS versus SLE-SS, such as dry mouth, dry eye, and a unique
                              autoantibody profile associated with pSS, were identified. In Yang’s study, we found that
                              the frequency of dry mouth and dry eye was significantly higher in SLE-SS than in the
                              SLE group [18]. Most previous studies have shown that anti-SSA/Ro and anti-SSB/La
                              antibodies are significantly more positive in SLE-SS than in the SLE group [19]. Regarding
                              RF positivity, Santos and Manoussakis et al. showed that RF positivity was significantly
                              higher in both SLE-SS groups than in the SLE group [20]. Our results were largely consistent
                              with previous studies. We conclude that dry mouth, dry eye, anti-Ro52 positive, anti-SSB
                              positivity, and RF positivity are risk factors for SLE progressing to SLE-SS. Therefore, we
                              should be aware of the development of combined SS when young SLE patients present
                              with dry mouth, dry eye, or positive anti-Ro52, anti-SSB, or RF.
                                    Meanwhile, patients with SLE-SS also have some clinical characteristics and autoan-
                              tibody profiles specific to SLE. Szanto and Manoussakis et al. showed a higher rate of
                              anti-dsDNA antibody positivity in SLE-SS than in the SS group and a significantly higher
                              frequency of hypoalbuminemia in SLE-SS than in the SS group [10,11]. Patients with SLE-SS
                              are also more likely to have renal involvement, such as proteinuria and hematuria. The
                              study by Szanto and Yang et al. suggests that SLE-SS patients are more likely to develop
                              renal damage than patients with SS [20,21]. In our study, we constructed a predictive
                              model with risk factors such as proteinuria, hematuria, hypoalbuminemia, and positive
                              anti-dsDNA antibodies, suggesting that when SS patients present with these symptoms,
                              they are more likely to have combined SLE.
                                    There are several limitations of this study. First, our collected data are retrospective,
                              and various biases are inevitable due to the nature of the study itself, even though all three
                              groups of patients were subjected to the same conditions and criteria to avoid selection bias
                              and confounding factors. Second, the sample size was relatively small, and we welcome
                              external validation in a wider population.

                              5. Conclusions
                                   Based on the patient’s clinical symptoms, the development of SS should be monitored
                              when SLE patients are positive for anti-RO52, anti-SSB, and RF. However, the presence
                              of SS patients with albuminuria, hematuria, hypoproteinemia, positive anti-dsDNA, and
                              positive anti-SM may indicate the presence of SLE. On the basis of clinical symptoms and
                              serum indicators, this study established a risk prediction model for SLE or SS transitioning
                              into SLE-SS with high accuracy, which may help with early diagnosis and the selection of
                              appropriate treatment.

                              Supplementary Materials: The following supporting information can be downloaded at: https:
                              //www.mdpi.com/article/10.3390/jcm12020535/s1, Table S1: Patient demographic and clinical
                              characteristics in the discovery and validation cohorts; Table S2: Clinical characteristics of SLE and
                              SLE-SS in the discovery and validation cohorts; Table S3: Clinical characteristics of SS and SLE-SS in
                              the discovery and validation cohorts.
                              Author Contributions: Y.H. and L.M. collected the data. Y.H. analyzed the results and drafted the
                              manuscript. X.F. designed and supervised the project and edited the manuscript. Z.J., D.W., Y.Z.,
                              B.H., H.W. and S.C. helped with data collection and analysis. All authors have read and agreed to the
                              published version of the manuscript.
J. Clin. Med. 2023, 12, 535                                                                                                         9 of 10

                                  Funding: This work was supported by the National Key Research and Development Program of
                                  China (2019YFE0111700) and the National Natural Science Foundation of China (No.81971517).
                                  Institutional Review Board Statement: The study was approved by the Ethics Committee of Drum
                                  Tower Hospital (No. 2020-093).
                                  Informed Consent Statement: The consent is waived because it is a retrospective chart review study.
                                  Data Availability Statement: Data are available on request from the corresponding author.
                                  Conflicts of Interest: The authors declare no conflict of interest.

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