摘要
目的：评估中性粒细胞与淋巴细胞比值（neutrophil-to-lymphocyte ratio，NLR）和全身免疫炎症指数（systemic immune- inflammation index，SII）在预测抗黑色素瘤分化相关基因5阳性皮肌炎（anti-melanoma differentiation-associated gene 5-positive dermatomyositis，抗MDA5+ DM）患者发展为快速进展型间质性肺病（rapidly progressive interstitial lung disease，RPILD）的预测价值。方法：回顾性分析2019年3月—2023年9月南京医科大学第一附属医院124例抗MDA5+ DM患者的临床和实验室资料，采用 Cox 回归分析确定与 RPILD 发展和病死率相关的独立危险因素。进行受试者工作特征（receiver operating characteristic， ROC）曲线分析，以确定预测不良结局的最佳临界值。结果：124例患者中，36例（29.03%）发生RPILD，39例（31.45%）在随访期间死亡。多因素Cox回归分析发现NLR升高是RPILD的独立危险因素，而SII升高与病死率独立相关。根据ROC曲线确定， NLR>6.12是RPILD的预测因子，SII>875.79时死亡风险增加。结论：NLR和SII是抗MDA5 + DM患者简单、经济、可靠的预后指标，为临床管理和风险分层提供了有价值的指导。
关键词
Abstract
Objective：To evaluate the predictive value of the neutrophil-to - lymphocyte ratio（NLR）and the systemic immune-inflammation index（SII）in predicting patients with anti-melanoma differentiation-associated gene 5 - positive（anti-MDA5 + ） dermatomyositis（DM）develop into the rapidly progressive interstitial lung disease（RPILD）. Methods：We retrospectively analyzed the clinical and laboratory data of 124 anti-MDA5 + DM patients from the First Affiliated Hospital of Nanjing Medical University between March 2019 and September 2023. We identified independent risk factors associated with the development and mortality of RPILD with the Cox regression analysis，and determined the optimal cut-off values for predicting adverse outcomes with the receiver operating characteristic（ROC）curve analysis. Results：Among the 124 patients，36 patients（29.03%）developed RPILD，and 39 patients（31.45%）died during the follow-up period. The results of multivariate Cox regression analysis showed that the elevated NLR was an independent risk factor for RPILD development，while the elevated SII expression was independently associated with the increased mortality of RPILD. Based on the ROC curve analysis，NLR>6.12 was a predictor for RPILD，and SII >875.79 was associated with increased mortality risk of RPILD. Conclusion：Both NLR and SII are accessible，cost-effective，and reliable prognostic indicators for the prognosis of patients with anti-MDA5+ DM，providing a valuable guidance for clinical management and risk stratification of the disease.
Anti⁃melanoma differentiation⁃associated gene5⁃ positive（anti ⁃ MDA5 +）dermatomyositis（DM）is a unique subtype of idiopathic inflammatory myositis characterized by a high risk of developing interstitial lung disease（ILD）[1] . Among these patients，approxi⁃ mately 38%-71% of patients develop into rapidly pro⁃ gressive interstitial lung disease（RPILD）[2-3]，a severe and life⁃threatening complication that is often resistant to current treatment. Despite aggressive therapy，the all⁃ cause mortality rate within six months of the patients remains as high as 40%-60%[4-6] . Several biomarkers， including the elevated expression of serum ferritin （SF）[7-8]，Krebs Von den Lungen⁃6（KL⁃6）[9]，and lac⁃ tate dehydrogenase（LDH）[10]，as well as the presence of anti⁃Ro52 antibodies[11-12]，have offered valuable in⁃ sights into the progression of anti⁃MDA5+ DM. However， because of the complexity and inherent variability of these markers，it highlights the urgent need for other novel and more reliable biomarkers that better predict RPILD of anti⁃MDA5+ DM patients in clinical practice.
The neutrophil ⁃ to ⁃ lymphocyte ratio（NLR）is a cost⁃effective and readily available indicator of systemic inflammation，which is increasingly recognized in vari⁃ ous inflammatory and autoimmune diseases，including sepsis，pneumonia，corona virus disease2019（COVID⁃ 19），rheumatoid arthritis（RA），systemic lupus erythe⁃ matosus，etc. [13-14] . High NLR was associated with poor prognosis in conditions like idiopathic pulmonary fibro⁃ sis，primary Sjögren’s syndrome，and RA ⁃ associated ILD[10，15-20] .
Similarly，the systemic immune ⁃inflammation in⁃ dex（SII），calculated as（platelet count × neutrophil count）/lymphocyte count，is another promising bio⁃marker that reflects the balance between immune re⁃ sponse and inflammation[13，21-24] . The SII expression was associated with disease activity of RA，adult⁃onset Still’s disease，and ankylosing spondylitis，and it also served as a prognostic indicator in conditions such as psoriasis，psoriatic arthritis，and anti ⁃ neutrophil cyto⁃ plasmic antibody ANCA⁃associated vasculitis[22-27] .
Studies found that the cytokine profiles of lung tis⁃ sues observed in patients with anti⁃MDA5+ DM⁃associ⁃ ated RPILD had similarities to those seen in severe cases of COVID ⁃ 19，where both NLR and SII were proven to be reliable predictors of disease severity and mortality[28-31] . These similarities suggest that NLR and SII may be valuable and easily integrated markers in routine clinical practice for monitoring inflammation and predicting outcomes in anti ⁃MDA5 + DM patients， which remains to be further explored. Therefore，the current study investigated the potential of both NLR and SII in predicting the prognosis of patients with anti⁃ MDA5+ DM.
1 Materials and methods
1.1 Study subjects
The current single ⁃center retrospective study was conducted at the First Affiliated Hospital of Nanjing Medical University and enrolled patients with anti ⁃ MDA5 + DM who received inpatient treatment between March 2019 and September 2023. All DM cases met the diagnostic criteria of Bohan ⁃ Peter 1975 or Son⁃ theimer[32-33]and were positive for MDA5 antibodies. The diagnosis of ILD was based on respiratory symp⁃ toms，physical examination，and high ⁃ resolution CT （HRCT）findings[34] . RPILD was defined as a progres⁃sive worsening of respiratory distress over one month， along with one of the following conditions[35-36]：① acute worsening of dyspnea requiring hospitalization or sup⁃ plemental oxygen；② a decrease in forced vital capac⁃ ity（FVC）of more than 10% or a decrease in diffusing capacity of the lungs for carbon monoxide（DLCO） with FVC greater than 15%；③ an increase in the extent of interstitial lung lesions over 20% based on chest HRCT；④ respiratory failure or a decrease in partial pressure of oxygen over 10 mmHg based on the arterial blood gas analysis. Two professional radiolo⁃ gists evaluated all HRCT images. All patients enrolled in the study were sampled for laboratory test prior to receiving systemic drug therapy from the center. The current study was approved by the Institutional Review Board of the First Affiliated Hospital of Nanjing Medi⁃ cal University（Jiangsu Provincial Hospital）（ethics No.2020⁃SR⁃265）.
1.2 Data collection
Demographic，clinical，and laboratory data as well as baseline glucocorticoid doses were collected and an⁃ alyzed. Baseline laboratory data included white blood cell count（WBC），absolute neutrophil count（NEU）， absolute lymphocyte count（LYC），absolute monocyte count（MON），platelet count（PLT），alanine amino⁃ transferase（ALT），aspartate aminotransferase（AST）， lactate dehydrogenase（LDH），creatine kinase（CK）， erythrocyte sedimentation rate（ESR），C ⁃ reactive pro⁃ tein（CRP），serum ferritin（SF），fibrinogen（FIB），D⁃di⁃ mer（D ⁃D），myositis ⁃ specific antibodies（MDA5 anti⁃ bodies），and myositis⁃associated antibodies（Ro52 anti⁃ bodies）. All glucocorticoids were converted to predni⁃ sone ⁃equivalent doses. Follow ⁃ up time was calculated from the first visit to our center to death or the last fol⁃ low⁃up. NLR was defined as the NEU divided by LYC. SII was defined as（PLT×NEU）/LYC[37] .
1.3 Statistical analysis
All data analyses were performed using R version 4.1.3. The Shapiro ⁃ Wilk test was used for normality testing. The t⁃test or Wilcox rank⁃sum test was applied for continuous variables with skewed distributions，and the Chi⁃square test or Fisher’s exact test was used for categorical variables. The data were presented as fol⁃ lows：mean ± standard deviation（）for normally dis⁃tributed continuous variables，median and interquartile range[M（P25，P75）]for non ⁃ normally distributed con⁃ tinuous variables，and numbers（percentages）[n（%）] for categorical variables. The univariate Cox analysis was performed followed by multivariate analysis. Step⁃ wise regression was used to screen variables based on univariate analysis（P <0.100）to identify independent risk factors affecting RPILD and survival. The diagnos⁃ tic and prognostic values of NLR and SII were calculated using the receiver operating characteristic（ROC）curve analysis and the area under the curve（AUC）. Survival analysis was calculated using the Kaplan ⁃Meier meth⁃ od，and the log⁃rank test was used to compare survival curves. All statistical tests were two⁃sided，and a P⁃value of less than 0.05 was considered statistically signifi⁃ cant.
2 Results
2.1 Baseline clinical characteristics
A total of 126 patients were initially enrolled in the current study，while two cases with gastric adeno⁃ carcinoma and pancreatic adenocarcinoma（no new tu⁃ mor events observed during the follow⁃up period）were included，two cases excluded because of missing core data. The mean follow⁃up duration in the current study was 13.23 months，with a median disease duration of 5.36 months. The mean age of the patients was（51.82± 13.33）years，and 49 cases（49/124，39.52%）were male. During the follow⁃up period，12 patients（12/124， 9.68%）did not develop ILD，75 patients（75/124， 60.48%）developed ILD but not RPILD，and 37 pa⁃ tients（37/124，29.84%）developed RPILD. The mortality rate in patients with RPILD was 78.38%，whereas in the non ⁃RPILD patients，it was 21.62%（P <0.001）. Meanwhile，the3⁃month，6⁃month and 12⁃month all ⁃ cause mortality rate were found to have significantly significant differences between the two groups（P <0.001）（Table 1）.
The patients were divided into the non ⁃ RPILD and RPILD groups. We found statistically significant differences between the two groups in terms of age， LYC，PLT，AST，LDH，CRP，SF，NLR and SII. Specifi⁃ cally，compared with those in the non ⁃ RPILD group， patients in the RPILD group were older[（55.73 ±12.57）years vs.（50.16±13.36）years，P=0.03]，had low⁃ er LYC levels（median：0.73×109 /L vs. 0.98×109 /L，P= 0.003），lower PLT levels（median：168.00 × 109 /L vs.179.00×109 /L，P=0.023），higher NLR levels（6.74 vs.3.92，P=0.003），higher SII levels（1 206.81 vs.716.83， P=0.014），higher AST levels（median：62.40 U/L vs.48.60 U/L，P=0.005），higher LDH levels（median： 344.00 U/L vs.288.00 U/L，P=0.012），higher CRP levels（median：9.15 mg/L vs.3.96 mg/L，P=0.001）， and higher SF levels（median：977.70 mg/mL vs.547.20 mg/mL，P=0.001）（Table 1）.
Furthermore，we observed a significant difference in myositis⁃associated antibodies，with a higher rate of anti⁃Ro52 antibody positivity in the RPILD group than in the non ⁃ RPILD group（86.49% vs.67.82%，P= 0.044）. Baseline data of glucocorticoid（GC）usage also differed significantly between the two groups（P= 0.014）. In the non ⁃RPILD group，27 cases（31.03%） used no GC at baseline，26 cases（29.89%）used high⁃ dose GC，and only 1 case（1.15%）used mega⁃dose GC. In contrast，in the RPILD group，17 cases（45.95%） used no GC at baseline，16 cases（43.24%）used high⁃ dose GC，and none used mega⁃dose GC. There were no statistically significant differences between the two groups regarding the percentage of males as well as the levels of WBC，NEU，MON，ALT，CK，ESR，FIB， D⁃D，baseline average dose of GC and anti⁃MDA5 anti⁃ bodies（Table 1）.
2.2 Risk factor analysis for RPILD and mortality in anti⁃MDA5+ DM
In the current study，we analyzed the risk factors for developing RPILD and mortality in patients with anti ⁃ MDA5 + DM，respectively. Univariate analysis re⁃ vealed that age and serum biomarkers（i.e.，NLR，PLR， SII，SIRI，and AISI）were positively correlated with the risk of developing RPILD[hazard ratio（HR）>1，P <0.05，respectively]. A higher LMR was identified as a protective factor against RPILD（Table 2）. In the multi⁃ variate Cox regression analysis，a high NLR remained the strongest independent risk factor for RPILD[HR= 1.11，95% confidence interval（CI）：1.03-1.18，P= 0.003]（Table 2）.
To assess the risk of mortality，variables that showed significant differences in the univariate analysis（i.e.，age，NLR，LMR，SII，SIRI，AISI，and myasthenia） were included in the multivariate model. The multivari⁃ ate Cox regression analysis indicated that a high SII was an independent risk factor for mortality（HR=1.00， 95% CI：1.00-1.00，P <0.05）. Increasing age was also a significant determinant of mortality risk（Table 3）.
2.3 Analysis of the value of NLR and SII on the prognosis of anti⁃MDA5+ DM
NLR and SII were identified as independent risk factors for poor prognosis，specifically for the develop⁃ ment of RPILD and overall survival，respectively. The ROC curve analysis was used to determine the optimal cut ⁃off values for predicting RPILD and survival（Fig⁃ ure1A，B）. The AUC for NLR in predicting RPILD was 0.67，with a cut⁃off value of 6.12. This cut⁃off value indicated a sensitivity of 56.76% and a specificity of 77.01%，suggesting moderate accuracy. Similarly，the AUC for NLR in predicting survival was 0.73，with the same cut ⁃ off value of 6.12，reflecting a sensitivity of 62.16% and a specificity of 79.31%，indicating a good accuracy. Regarding SII，the AUC for predicting RPILD was 0.64，with a cut⁃off value of 1 200.82，dem⁃ onstrating a sensitivity of 51.35% and a specificity of 78.16%. The AUC for SII predicting survival was 0.69， with the cut⁃off value of 875.79，reflecting a sensitivity of 72.97% and a specificity of 62.07%，indicating that SII was a moderately accurate predictor（Table 4）.
2.4 Survival analysis of anti⁃MDA5+ DM
Among patients with anti⁃MDA5+ DM，there was a significant association between SII，NLR and RPILD （P=0.001 and P <0.001）. When stratified by the opti⁃ mal cut ⁃ off value of SII，the Kaplan ⁃ Meier survival curve revealed that patients with SII>1 200.82 had a significantly lower incidence of non⁃RPILD within one year，compared to those with SII≤1 200.82（P=0.001， Figure 2A）. Figure 2B showed that patients with an NLR≤6.12 had a significantly lower incidence of non ⁃ RPILD than those with an NLR>6.12（P <0.001）.
Furthermore，SII and NLR were found to be signifi⁃ cantly associated with mortality（P <0.001）. Patients with SII>875.79 had a significantly lower survival rate within one year，compared to those with SII≤875.79 （Figure 3A）. While，patients with NLR>6.12 had a lower survival rate than those with NLR<6.12（Figure 3 B）.
表1Anti⁃MDA5+ DM患者的临床特征
Table1Clinical characteristics of anti⁃MDA5+ DM patients
WBC：white blood cell count；NEU：absolute neutrophil count；LYC：absolute lymphocyte count；MON：absolute monocyte count；PLT：platelet count；ALT：alanine aminotransferase；AST：aspartate aminotransfer⁃ ase；LDH：lactate dehydrogenase；CK：creatine kinase；ESR：erythrocyte sedimentation rate；CRP：C⁃reactive protein；SF：serum ferritin；FIB：fibrinogen；D⁃D：D⁃dimer；GC：glucocorticoid.
表2anti⁃MDA5+ DM患者发生RPILD独立危险因素的单因素和多因素分析
Table2Univariate and multivariate analysis of the independent risk factors of RPILD in anti⁃MDA5+ DM patients
PLR：platelet⁃to⁃lymphocyte ratio；NLR：neutrophil⁃to⁃lymphocyte ratio；LMR：lymphocyte⁃to⁃monocyte ratio；SII：systemic immune⁃inflammation index；SIRI：systemic inflammation response index；ILD：interstitial lung disease；Glu：glucose；Inf：infinity；CI：confidence interval.
3 Discussion
Anti⁃MDA5+ DM is frequently associated with in⁃ terstitial lung disease，particularly RPILD which has impressively high mortality[1] . The interactions of pe⁃ ripheral blood cells play a crucial role in regulating in⁃ flammation and immune responses. Neutrophils，lym⁃ phocytes，and platelets are vital effector cells in the inflammatory response[38-40] . Consequently，the derived inflammatory indices，such as NLR and SII，have gained attention for their ability to comprehensively as⁃ sess the inflammatory status in patients with systemic autoimmune diseases，including anti⁃MDA5+ DM[12] . In the current study，we aimed to screen prognostic fac⁃ tors affecting anti⁃MDA5 + DM and highlight its poten⁃ tial significance in clinical practice.
We found that the NLR was the most significant prognostic biomarker for RPILD in patients with anti ⁃ MDA5+ DM. According to previous studies，NLR was an important marker for evaluating the activity of RA[41-42] and predicting the risk of death[43] . Additionally，NLR was associated with the activity of leukoaraiosis syn⁃ drome[44-45] and a predictor of psoriatic arthritis[46-47] . It has also been correlated with the activity of systemic lupus erythematosus and the prediction of lupus ne⁃ phritis[48] . In cases of pulmonary fibrosis in ILD，fibro⁃ blasts and myofibroblasts proliferate and deposit exces⁃sive extracellular matrix（ECM）in the interstitium， leading to an impaired lung function[49] . Neutrophils play a crucial role in this process by releasing elastase and matrix metalloproteinases to degrade ECM pro⁃teins and activate transforming growth factor⁃β（TGF⁃β）， thus promoting further ECM accumulation. Addition⁃ ally，neutrophil extracellular traps stimulate the TGF ⁃ β production and activate myofibroblasts，leading to en⁃ dothelial damage and the increased infiltration of in⁃ flammatory cells in the lungs，exacerbating interstitial inflammation and fibrosis[15] . The role of lymphocytes in this process is complex and somewhat controversial. For example，the activated human T lymphocytes inhibit the TGF⁃β⁃induced fibroblast differentiation into myo⁃ fibroblasts through prostaglandin D[49] . On the other hand，Th1 cells alleviate fibrosis by secreting interleu⁃ kin⁃12（IL⁃12）and interferon⁃γ [15] .
表3anti⁃MDA5+ DM患者死亡独立危险因素的单因素和多因素分析
Table3Univariate and multivariate analysis of the independent risk factors of death in anti⁃MDA5+ DM patients
PLR：platelet⁃to⁃lymphocyte ratio；NLR：neutrophil⁃to⁃lymphocyte ratio；LMR：lymphocyte⁃to⁃monocyte ratio；SII：systemic immune⁃inflammation index；SIRI：systemic inflammation response index；ILD：interstitial lung disease；Glu：glucose；Inf：infinity；CI：confidence interval.
图1NLR和SII在预测RPILD（A）与存活（B）的ROC分析
Figure1ROC analysis of both NLR and SII in predicting RPILD（A）and survival（B）
表4NLR和SII对RPILD和生存的预测价值
Table4表4 The predictive value of NLR and SII for RPILD and survival
图2低/高SII（A）、低/高NLR（B）分层的非RPILD anti⁃MDA5+ DM患者的Kaplan⁃Meier生存曲线
Figure2Kaplan⁃Meier survival curve of anti⁃MDA5+ DM patients with non⁃RPILD stratified by low/high SII（A）and low/ high NLR（B）
图3低/高SII（A）、低/高NLR（B）分层的anti⁃MDA5+ DM患者总体生存的Kaplan⁃Meier生存曲线
Figure3Kaplan⁃Meier survival curves for overall survival of anti⁃MDA5+ DM patients stratified by low/high SII（A）and low/high NLR（B）
In healthy adult non ⁃ elderly populations，normal NLR values range from 0.78 to 3.53，with a mean value of 2.8 in patients with connective tissue conditions[50] .In the current study，patients with a poor prognosis had elevated NEU，decreased LYC，and consequently ele⁃ vated NLR，consistent with previous studies[44-48，50-51] . The development of ILD is associated with the over ⁃ activation of alveolar macrophages，which triggers neutrophil activation and the release of lymphocyte chemotactic factors[52-53]，further leading to an increase in NLR. For instance，in patients with systemic sclerosis， an NLR value higher than 2.59 helps predict ILD[50]；in polymyositis and dermatomyositis，NLR is significantly correlated with the presence of ILD and serves as an independent predictor of its occurrence[54] . Therefore， NLR is closely associated with ILD[50] . In the current study，the mean NLR value was 3.92 in non ⁃RPILD patients and 6.74 in RPILD patients（P=0.003）. After conducting an ROC curve analysis，the best cut ⁃ off value for NLR in predicting RPILD was consistent with that of mortality，which was 6.12，indicating a strong association with a fatal outcome，especially when com⁃ bined with RPILD. Compared with recent studies，NLR higher than 4.86 was used as an independent predictor of mortality in patients with anti ⁃MDA5 + DM[14] . It is worth noting that the optimal cut⁃off value may differ in other studies because of factors such as sample size and analysis methods. Therefore，further research with larger sample sizes and multi ⁃ center studies is neces⁃ sary to determine a more definitive prediction.
SII is a newly developed index that measures in⁃ flammation by combining peripheral lymphocytes，neu⁃ trophils，and platelets，providing a more comprehen⁃ sive assessment of inflammation and immune balance in the body. SII can be used to evaluate disease activity and predict adverse outcomes. From a pathophysiologi⁃ cal perspective，inflammation leads to an increase in neutrophil and platelet counts as well as a decrease in lymphocyte counts，which results in higher SII values that indicate stronger inflammatory responses and weaker immune responses[55] . In the assessment of can⁃ cer，an elevated SII is significantly associated with lower survival rates，and the median critical value for SII was 572[37]，with a value above600 serving as a clinical marker of inflammation[50] . Studies have shown that when the critical value exceeds 578.25，there is a sig⁃ nificant increase in the risk of developing RA[25] . In an⁃ kylosing spondylitis patients，an SII critical value of 513.20 yielded a sensitivity of 86.84% and specificity of 83.33% for diagnosing disease activity[27] . In the cur⁃ rent study，the mean SII value for surviving patients was 694.55，while for deceased patients，it was 1 278.43 （P=0.001）. SII was significantly associated with mor⁃ tality in anti⁃MDA5+ DM patients，with a cut⁃off value above895.79 indicating an increased risk of death. Additionally，the current study showed that age was an independent risk factor for predicting mortality in anti⁃ MDA5 + DM，consistent with previous findings，which may be due to older patients having more comorbidi⁃ ties and overall poorer health[56-57] .
In summary，NLR and SII are valuable tools for clinicians in assessing disease severity，monitoring in⁃ flammation，and predicting poor prognosis in anti ⁃ MDA5 + DM patients[54] . These parameters offer greater diagnostic and predictive accuracy than single indica⁃ tors because they provide a more comprehensive as⁃ sessment of the inflammatory response. Although the exact cause of anti ⁃MDA5 + DM remains unknown，re⁃ cent studies have correlated disease prognosis with sev⁃ eral factors，including anti⁃MDA5 antibody titers，high ferritin levels，serum KL⁃6，serum LDH levels，and the proportion of CD4+ CXCR4+ T cells[3，58-59] . Besides，stu⁃ dies have shown that peripheral LYC is correlated with RPILD and is an applicable prognostic predictor for an⁃ ti⁃MDA5+ DM[60] . Compared with these indicators，both NLR and SII are simpler，faster，and more cost ⁃ effec⁃ tive，making them particularly useful for dynamic moni⁃ toring in clinical practice.
However，the current study has several limitations. Firstly，the follow ⁃ up period for recently enrolled pa⁃ tients was relatively short，which may introduce some bias. Secondly，because of the rarity of the disease，the sample size was relatively small. Thirdly，the study was limited to a single center，and future multicenter stud⁃ ies are needed to validate the results. Lastly，lympho⁃ cyte，neutrophil，and platelet counts may be influenced by treatment regimens；however，most cases in the study had received steroid treatment，making it diffi⁃ cult to exclude this factor. Prospective studies are nec⁃ essary to evaluate changes in NLR and SII at different disease stages. Future efforts should focus on design⁃ing large ⁃scale，multicenter，prospective studies to ex⁃ plore the application value of NLR and SII in anti ⁃ MDA5+ DM patients.
Availability of data and materials：
The datasets used during the current study are available from the corresponding author upon reasonable request.
Conflict of Interests：
The authors declare that they have no competing interest.
Author’s Contributions：
TAN Wengfeng designed the study. CAI Qingqing contrib⁃ uted to the study design. YOU Hanxiao，LÜ Chengyin，WANG Lei，QIU Yulu，and SHI Yumeng recruited patients and ob⁃ tained consent for the study. CAI Qingqing and WU Lingyun an⁃ alyzed and interpreted the data. CAI Qingqing，WANG Fang， ZHANG Miaojia，and TAN Wenfeng wrote the manuscript. All authors read，revised，and approved the final version of the man⁃ uscript.
Acknowledgements：
We thank all authors for their continuous and excellent sup⁃ port with patients’data collection，data analysis，statistical anal⁃ ysis，and valuable suggestions for the article. Thanks to Dr. SHEN Sipeng and Dr. LI Hongru，School of Public Health，Nan⁃ jing Medical University for their help in statistics.
