PERK signaling activation restores nucleus pulposus degeneration by activating autophagy under hypoxia environment

OBJECTIVES

Intervertebral disc (IVD) degeneration is an important disease with no efficient biological therapy identified. Autophagy, a wildly known therapeutic target for human disease, has been demonstrated to be activated under hypoxia, with underlying mechanism remains elusive. Thus, this study aims to specify the role of autophagy in IVD degeneration, the regulating mechanism of hypoxia-inducing autophagy, and the therapeutic value of autophagy for IVD degeneration.

METHODS

RNA-seq was used to screen the primary pathway affected in NP cells under hypoxia, the specific link between hypoxia and autophagy were investigated using ChIP-seq and dual luciferase reporter assay. Conditional ATG7 knockout mice (ATG7^-/-) were constructed for assessing the effect of autophagy on IVD degeneration, and puncture induced mice model of IVD degeneration were used for intradiscal injection to evaluate the therapeutic value of autophagy.

RESULTS

We demonstrated that hypoxia induces autophagy by transcriptional activation of autophagic gene LC3B and ATG7, which is controlled by PERK signaling. Then, we observed that inhibiting autophagy or PERK signaling leads to impaired NP cell viability and function, furthermore, using ATG7 knockout (ATG7^-/-) mice, we identified the protective role of autophagy in IVD. Furthermore, we found that intradiscal injection of PERK signaling agonist, CCT020312, significantly restores the degeneration level of needle punctured mice IVD.

CONCLUSION

We showed that the activation of PERK signaling upon hypoxia serves as a vital mechanism to induce autophagy and identified the therapeutic value of PERK signaling agonist for IVD degeneration treatment.

Global Trends of Researches on Lumbar Spinal Stenosis: A Bibliometric and Visualization Study

STUDY DESIGN

Bibliometric and visualization analysis.

OBJECTIVE

Lumbar spinal stenosis (LSS) has become a common health problem and the most frequent indication for spinal surgery. This study aimed to illustrate the overall knowledge structure, and development trends of LSS, using a bibliometric analysis and newly developed visualization tools.

MATERIALS AND METHODS

Research data sets were acquired from the Web of Science. The time span was defined as "2000-2019". VOS viewer and Citespace software was provided to analyze the data and generate visualization knowledge maps. Annual trend of publications, distribution, H-index status, co-authorship status and research hotspots were analyzed.

RESULTS

A total of 1934 publications met the requirement. The United States published most papers (521, 26.9%), both total citations (17,626) and H-index (61) ranked first of all the countries. The most productive organizations on LSS is Seoul National University (50). Spine (43) published the most papers on LSS. Quality of life, risk factor, disability, double blind trials, and decompression surgery are the research hotspots in the recent years.

CONCLUSION

The number of publications showed an upward trend with a stable rise in recent years. The United States is a country with the highest productivity, not only in quality, but also in quantity. Seoul National University has been the largest contributor in this field. Spine is the best journal related to LSS. Quality of life, risk factor, disability, and decompression surgery are the research hotspots in the recent years. Indeed, this study provides a new insight to the growth and development of LSS. Moreover, it will contribute to the growth of the international frontier of LSS.

Correlation and Differences in Lumbopelvic Sagittal Alignment Parameters Between Lumbar Radiographs and Magnetic Resonance Images

STUDY DESIGN

Imaging parameter study.

OBJECTIVE

Though lumbar alignment is better evaluated using standing radiograph than supine magnetic resonance imaging (MRI), few studies have researched this. Our study aimed to observe the correlation and difference in alignment between standing radiograph and supine MRI, and assess whether the change of position affects the lumbopelvic parameters.

METHODS

We analyzed 105 patients, measuring lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI). Inter- and intraparameter analyses were performed to identify any difference between standing radiograph and supine MRI. Statistical differences between the lumbopelvic parameters were compared.

RESULTS

There was excellent interobserver agreement for each parameter (interclass correlation coefficient > 0.75), and significant differences were observed in each parameter between radiograph and MRI (P < .05). Strong correlations were noted between the equivalent parameters in radiograph and MRI, both SS and PI were strongly correlated with LL in radiograph and MRI image, both PT and SS were strongly correlated with PI in radiograph and MRI image (r = -1.0 to -0.5 or 0.5 to 1.0).

CONCLUSION

Supine MRI obviously underestimated the measurements of lumbopelvic sagittal alignment parameters in standing radiograph. Therefore, standing lumbar radiographs should be obtained preoperatively in all surgical patients, not only supine MRI. In addition, we observed that PI was not a constant morphological parameter.

[Association between CD137 and ischemia-reperfusion injury in patients with acute ST-segment elevation myocardial infarction]

Objective: To explore the relationship between the levels of serum soluble CD137 (sCD137) and membrane-bound CD137 (mCD137) and the occurrence of ischemia reperfusion injury (IRI) in patients with acute ST-segment elevation myocardial infarction (STEMI). Methods: This is a cross-sectional study. Consecutive patients with acute STEMI, who underwent emergency percutaneous coronary intervention (PCI) in the Department of Cardiology, Jiangsu University Affiliated Hospital from May 2019 to September 2020, were enrolled. According to the absence or presence of IRI, patients were divided into IRI group and non-IRI group. Clinical data of the two groups were collected and compared. sCD137 level was detected by enzyme linked immunosorbent assay. Ficoll density gradient centrifugation was used to separate peripheral blood mononuclear cells (PBMC) and RNA was extracted, mCD137 mRNA expression level was detected by PCR. Serum sCD137 levels and the mCD137 mRNA levels of PBMC before, after PCI and 24 hours after PCI were compared. The correlation between serum sCD137 level, PBMC mCD137 mRNA level and clinical indicators was observed. The univariate and multivariate logistic binary regression analyses were performed to evaluate the related risk factors of IRI. ROC curve was used to analyze the predictive value of defined parameters for IRI. Results: A total of 112 STEMI patients were enrolled. There were 42 cases (of which 33 were males (78.6%), mean age was (58.6±12.7) years) in non-IRI group and 70 cases(of which 56 were males (80.0%), mean age was (64.5±11.6) years) in IRI group. Compared with the non-IRI group, patients in the IRI group had longer hospital stays, older age, lower rates of obesity, lower systolic and diastolic blood pressure at admission, higher proportion of the the right coronary artery as culprit vessel, lower rate of the use of angiotensin-converting enzyme inhibitor/angiotensin-Ⅱ receptor blocker/angiotensin receptor neprilysin inhibitor, higher levels of urea nitrogen and creatinine, lower glomerular filtration rate, lower triglycerides, higher D-dimer and B-type natriuretic peptide_max, higher proportion of Killip grade Ⅳ and cardiovascular adverse events (all P<0.05). sCD137 levels at the preoperative, postoperative and 24 hours after surgery were significantly higher in the IRI group than in the non-IRI group, while the mRNA levels of CD137 was similar between the two groups. The level of sCD137 in patients after PCI was lower than that before operation, the level of mCD137 mRNA was higher than that before operation (P<0.05). Serum sCD137 levels were positively correlated with hospitalization days, age, B-type natriuretic peptide, creatinine, ischemic time, C Reactive protein (CRP) and CRP/albumin (P<0.05), and negatively correlated with body mass index, glomerular filtration rate and albumin (P<0.05). The mCD137 mRNA expression level of PBMC was positively correlated with hospital stay, age, B-type natriuretic peptide, ischemic time, CRP and CRP/albumin (P<0.05), and negatively correlated with body mass index, glomerular filtration rate, albumin (P<0.05). Multivariate logistic regression analysis showed that higher sCD137 (OR=1.038, 95%CI: 1.009-1.069), aspartate aminotransferase, (OR=1.029, 95%CI: 1.009-1.050) and lower albumin (OR=0.829, 95%CI: 0.703-0.829) before surgery were independent risk factors of IRI (P<0.05). Receiver operating characteristic curve showed that the area under the curve of sCD137 was 0.672 (95%CI: 0.574-0.770, P=0.002) for the prediction of IRI, the best cut-off value was 28.43×10^-3 μg/L with sensitivity of 95.2% and specificity of 48.6%. Conclusion: The significantly increased level of sCD137 in acute STEMI patients is positively correlated with reperfusion injury, which is an independent risk factor of IRI and may be related to the prognosis of patients with IRI.

[Prevalence of hyperkalemia and its effects on mortality in hospitalized patients: a single center 10-year retrospective analysis]

Objective: To investigate the prevalence of hyperkalemia in hospitalized patients, and analyze the effects of different serum potassium levels and change rates of serum potassium on the mortality of hospitalized patients. Methods: The clinical data of 944 446 hospitalized patients in Sichuan Provincial People's Hospital from January 2009 to December 2018 were retrospectively analyzed. Hyperkalemia is defined as serum potassium ≥ 5.5 mmol/L. The effects of serum potassium level and its change rate on hospitalized mortality were analyzed. Results: There were 15 771 patients with hyperkalemia, and the prevalence of hyperkalemia was 1.7% (15 771/944 446). However, the discharge diagnosis rate was only 11.0% (1 735/15 771), and the missed diagnosis rate was 89.0% (14 036/15 771). Cox regression analysis showed that serum potassium<3.5 mmol/L (HR=1.338, 95%CI: 1.164-1.537, P<0.001) or ≥ 6.5 mmol/L (HR=1.421, 95%CI: 1.158-1.744, P=0.001) increased the risk of hospitalized mortality compared with patients with normal serum potassium. Compared with the increased rate of serum potassium by 0.01-0.10 mmol/d, patients who reached the peak of serum potassium at admission (HR=1.251, 95%CI: 1.077-1.453, P=0.003), increased rate of serum potassium by 0.11-0.51 mmol/d (HR=1.499, 95%CI: 1.315-1.709, P<0.001) or >0.51 mmol/d (HR=2.431, 95%CI: 2.105-2.807, P<0.001) increased the risk of mortality. Of patients with hyperkalemia, those who did not repeat the serum potassium test had a higher risk of mortality (HR=1.656, 95%CI: 1.434-1.914, P<0.001). Conclusions: The prevalence of hyperkalemia in hospitalized patients was 1.7%, and the missed diagnosis rate was high at discharge. Patients who had hypokalemia at admission, severe hyperkalemia, rapid increased serum potassium, or failed to repeat serum potassium test during hospitalization, had higher risk of mortality.

[Deep learning reconstruction algorithm for coronary CT angiography in assessing obstructive coronary artery disease caused by calcified lesions: the clinical application value]

Objective: To investigate the image quality of coronary CT angiography (CCTA) subjected to deep learning-based reconstruction algorithm (DLR) method and its diagnostic performance for stenosis caused by coronary calcified lesions. Methods: We enrolled 33 consecutive patients with known or suspected coronary artery disease (CAD) who underwent CCTA and subsequently invasive coronary angiography (ICA) within 1 month in the department of radiology, Peking Union Medical College Hospital between February 2020 and February 2021. Among them, there are 26 males and 7 females, age range from 45 to 86 (61.9±9.0) years. The CCTA images were reconstructed with DLR and hybrid iterative reconstruction (HIR). Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated on the aorta root, left main artery, proximal left anterior descending, left circumflex, and right coronary artery of the CCTA images and were used to evaluate the objective image quality (IQ). Subjective IQ score was graded using Likert four-point scale (1 for excellent and 4 for poor). The diagnostic performance of obstructive coronary artery disease caused by calcified lesions on CCTA subjected to DLR and HIR methods were evaluated using ICA as the reference standard. Results: A total of 123 lesions in 33 patients were included in the analysis. Image noise of DLR image was significantly lower than that on HIR image(defined as the standard deviation of the attenuation values in the aortic root: 18.12±3.66 vs 24.19±5.71, P<0.001), CNR and SNR of DLR image in the aortic root were higher (CNR:43.83±23.73 vs 26.38±9.69, P<0.001,SNR:26.66±7.83 vs 21.23±8.65, P<0.001). Subjective scores of DLR was better than HIR image (1.12±0.41 vs 1.46±0.60,P<0.001). The sensitivity, specificity and accuracy of DLR and HIR images for diagnosing obstructive coronary artery disease caused by calcified lesions were 100.0%, 77.4%, 78.9% and 100.0%, 63.5%, 65.9%%, respectively. The number of false positive cases on DLR image decreased by 38% compared with HIR. Conclusions: Artificial intelligence based DLR can significantly reduce the image noise and improve the image quality of CCTA. DLR helps to improve the diagnostic performance of CCTA in assessing obstructive coronary artery disease caused by calcified lesions, which may have good clinical application value.

Probing Gluon Spin-Momentum Correlations in Transversely Polarized Protons through Midrapidity Isolated Direct Photons in p^{↑}+p Collisions at sqrt[s]=200 GeV

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200  GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

Plasma metabolite changes in anestrous dairy cows with negative energy balance identified using 1H NMR technology

ABSTRACT The objective of the present study was to investigate the different plasma metabolites between anestrus and estrus postpartum dairy cows and to provide a theoretical basis for prevention of anestrus in dairy farm cows. In the experiment, one hundred and sixty-seven Holstein dairy cows were selected with similar age and parity. According to the concentration of β-hydroxybutyric acid, non-esterified fatty acids and glucose in plasma during 14 to 21 days in milk, all dairy cows were determined as having a status of energy balance. According to the results of clinical symptom, rectal and B ultrasound examination at 60 to 90 days postpartum, these cows were divided into twenty estrus and twenty-four anestrus group, other dairy cows were removed. 1H nuclear magnetic resonance technology was utilized to detect the plasma metabolites changes and screen different plasma metabolites between anestrus and estrus cows. Ten different metabolites including alanine, glutamic acid, asparagine, creatine, choline, phosphocholine, glycerophosphocholine, low-density lipoprotein, and very-low-density lipoprotein were significantly decreased in anestrous cows compared with estrous cows. Metabolic pathway analyses indicated that differential metabolites were primarily involved in amino acid and glycerophospholipid metabolism. These metabolites and their enrichment pathways indicate that reduced steroid hormone synthesis precursors result in lower levels of estradiol and progesterone and cause anestrus in negative energy balance. These data provide a better understanding of the changes that may affect estrus of postpartum dairy cows at NEB status and lay the ground for further research.

Taraxasterol inhibits TGF-β1-induced epithelial-to-mesenchymal transition in papillary thyroid cancer cells through regulating the Wnt/β-catenin signaling

Taraxasterol (TAR) is a kind of active compound extracted from dandelion and its molecular structure resembles steroid hormones. Recently, TAR has been reported to show an anti-tumor activity. However, the specific role of TAR in papillary thyroid cancer (PTC) has not been clarified. In this study, we investigated the effect of TAR on PTC cell migration, invasion and epithelial-to-mesenchymal transition (EMT) induced by TGF-β1. PTC cells were exposed to TGF-β1 (5 ng/mL) and then treated with different concentrations of TAR. We found that TAR showed no obvious cytotoxicity below 10 μg/mL but notably reduced migration and invasion of TGF-β1-treated PTC cells. Moreover, TAR treatment decreased MMP-2 and MMP-9 levels, and obviously affected the expression of EMT markers. We also observed that Wnt3a and β-catenin levels were significantly increased in TGF-β1-treated PTC cells while TAR inhibited these effects in a concentration-dependent manner. Additionally, activation of the Wnt pathway by LiCl attenuated the suppressive effect of TAR on TGF-β1-induced migration, invasion and EMT in PTC cells. Taken together, we highlighted that TAR could significantly suppress TGF-β1-regulated migration and invasion by reversing the EMT process via the Wnt/β-catenin pathway, suggesting that TAR may be a potential anti-cancer agent for PTC treatment.

A Bibliometric Analysis and Visualization of Current Research Trends in the Treatment of Cervical Spondylotic Myelopathy

STUDY DESIGN

Bibliometric analysis.

OBJECTIVE

Cervical spondylotic myelopathy (CSM) has become the most common cause of spinal cord dysfunction. Many topics of CSM still remain controversial. This study aimed to illustrate the overall knowledge structure and development trends of CSM.

METHODS

Research data sets were acquired from the Web of Science database and the time span was defined as "2000 to 2019." VOS viewer and Citespace software was used to analyze the data and generate visualization knowledge maps. Annual trends of publications, distribution, H-index status, co-authorship status, and research hotspots were analyzed.

RESULTS

A total of 2367 publications met the requirement. The largest number of articles was from the United States, followed by Japan, China, Canada, and India. The highest H-index was found for articles from the United States. The highest number of articles was published in Spine. The cooperation between the countries, institutes, and authors were relatively weak. Cervical sagittal alignment, predictive factor, diffusion tensor imaging, and the natural history of CSM may become a frontier in this research field.

CONCLUSION

The number of publications showed an upward trend with a stable rise. Most of the publications are limited to a few countries and institutions with relatively weak interaction. The United States, Canada, Japan, China, and India have made significant contributions to the field of CSM. The United States is the country with the highest productivity, not only in quality but also in quantity. Cervical sagittal alignment, predictive factor, diffusion tensor imaging, and the natural history of CSM are the research hotspots in the recent years.

[Establishment of a 3D ultrasound imaging system based on pulse-triggered image acquisition]

OBJECTIVE

To establish a 3D ultrasound imaging system based on pulse-triggered image acquisition using the linear probe on the Verasonics^TM vantage 128 platform and evaluate its performance in scanning standard phantom and human carotid artery.

OBJECTIVE

The 3D ultrasound imaging system included 3 modules for probe motion control, image acquisition and storage, and 3D image reconstruction and display. To improve the precision of image acquisition, we used fixed frequency pulses to control the external trigger function combined with mechanical scanning. Voxel-based 3D reconstruction was used for image reconstruction and display. The user interface was designed to allow direct operations of the platform. We carried out scanning tests of standard ultrasound phantom and human carotid artery to evaluate the performance of this imaging system.

OBJECTIVE

We successfully constructed a 3D ultrasound imaging system based on pulse-triggered image acquisition. The results of standard phantom and human carotid scanning tests showed that each module of the system was fully functional. The self-designed user interface of this ultrasound imaging system allowed full control of the system functions for original image acquisition, 3D image reconstruction, and display of cross-sections in 3 different views.

OBJECTIVE

This 3D ultrasound imaging system achieves high-quality 3D ultrasound imaging and provides the basis for further study and clinical application of 3D ultrasound imaging.

Comparison of SDSG and CARDS classifications for L5/S1 lumbar degenerative spondylolisthesis: an independent inter- and intra-observer agreement study

BACKGROUND

Lumbar degenerative spondylolisthesis (DS) has been a common disease that makes increasing patients to suffer from different degrees of low back pain and radicular symptoms. The Spinal Deformity Study Group (SDSG) and the Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) systems are commonly used to classify the disease, and help to make a more detailed treatment plan. The objective of this study is to compare the reliability and reproducibility of SDSG and CARDS classifications, and to explore their clinical application value.

METHODS/DESIGN

All 117 patients with L5/S1 lumbar DS were enrolled. Five experienced spine surgeons were selected to assess DS with SDSG and CARDS systems. Kappa (K) value was used to check the coefficient consistency for multi-factor and assess the inter- and intra-observer agreement. After 12 weeks, the analysis was repeated.

RESULTS

The inter-observer reliability and intra-observer reproducibility of SDSG system were substantial with K values of 0.704 and 0.861, while those of CARDS system were substantial with values of 0.620 and 0.878.

CONCLUSION

SDSG system had better inter-observer reliability in comparison with CARDS system, and though CARDS system is more intuitive and simpler, it is more likely to produce deviations when using it. Both SDSG and CARDS systems show substantial agreement and have great significance in surgical strategy of L5/S1 lumbar DS, they can be widely used in clinical practice.

POS0219 EFFECT OF LOW-DOSE METHOTREXATE ON ESTIMATED GLOMERULAR FILTRATION RATE AND KIDNEY ADVERSE EVENTS IN THE CARDIOVASCULAR INFLAMMATION REDUCTION TRIAL

Background:

Low-dose methotrexate (LD-MTX) is a common first-line treatment for systemic rheumatic diseases, and its use is contraindicated in advanced chronic kidney disease (CKD) because it is primarily excreted by the kidneys. Among patients with preserved kidney function, the safety of LD-MTX on estimated glomerular filtration rate (eGFR) and kidney adverse events (AEs) has not been established.

Objectives:

To investigate the effect of LD-MTX on eGFR and kidney AEs using data from a randomized clinical trial.

Methods:

We performed a secondary analysis for eGFR and kidney AEs using the randomized double-blind, placebo-controlled Cardiovascular Inflammation Reduction Trial. Adults with known cardiovascular disease and diabetes and/or metabolic syndrome were randomly allocated to oral LD-MTX (target dose 15-20 mg/week) or placebo. All participants took folic acid 1 mg six days/week. Exclusion criteria included systemic inflammatory disease and creatinine clearance <40 mL/min (by Cockcroft-Gault). eGFR was calculated using the CKD-EPI formula. Clinical kidney AEs were blindly adjudicated. The least-squares mean change of eGFR from baseline was calculated at each study visit; the difference in eGFR slopes between LD-MTX and placebo was compared using a modified intention-to-treat approach. We also compared rates of kidney AEs for LD-MTX versus placebo using Cox proportional hazards models.

Results:

A total of 2,391 subjects were randomized to LD-MTX and 2,395 to placebo. At baseline, mean age was 66 years, 19% were female, mean eGFR was 80.0 mL/min/1.73m2, and 18% had stage 3 CKD or worse. Median follow-up duration was 23 months, and median LD-MTX dose was 16 mg/week. Those randomized to LD-MTX had less decline in eGFR over the entire follow-up compared to placebo (slope difference 1.12, 95%CI 0.59-1.65, p<0.001, Figure 1). Those with CKD stage 3 or worse on LD-MTX saw less eGFR decline than those with CKD stage 2 or better (slope difference among CKD stage 3 or worse: 2.46, 95%CI 1.10-3.82, p<0.001; p for interaction 0.02). The LD-MTX group had higher eGFR than placebo over the first 24 months of study follow-up (p<0.05 at each visit). On safety laboratory monitoring, there were 159 acute kidney injury AEs in the LD-MTX group and 187 in the placebo group (HR 0.83, 95%CI 0.67-1.02, Table 1). There were 37 clinical kidney AEs in the LD-MTX group and 42 in the placebo group (0.87, 95%CI 0.56-1.36). One subject began dialysis in the LD-MTX group compared to 3 in the placebo group.

Table 1.

Rates and hazard ratios for kidney adverse events per random assignment of low-dose methotrexate or placebo in the Cardiovascular Inflammation Reduction Trial (n=4,786).

Low-dose methotrexate (n=2,391)Placebo (n=2,395) (reference)HR (95%CI)EventsRate per 100 person-years (95%CI)EventsRate per 100 person-years (95%CI)SCr collected at safety visitsAny event*1593.42 (2.93, 3.98)1874.06 (3.53, 4.67)0.83 (0.67, 1.02)Mild (SCr 1.5-1.9x baseline)1543.47 (2.97, 4.06)1774.06 (3.51, 4.69)0.85 (0.68, 1.06)Moderate (SCr 2-2.9x baseline)190.41 (0.26, 0.64)240.52 (0.35, 0.78)0.78 (0.43, 1.43)Severe (SCr ≥3x baseline)20.04 (0.01, 0.17)50.11 (0.05, 0.26)0.40 (0.08, 2.04)Adjudicated clinical kidney adverse eventsAny event*370.80 (0.58, 1.11)420.92 (0.68, 1.24)0.87 (0.56, 1.36)Mild240.52 (0.35, 0.77)250.55 (0.37, 0.81)0.95 (0.55, 1.67)Moderate110.24 (0.13, 0.43)110.24 (0.13, 0.43)1.00 (0.43, 2.29)Severe40.09 (0.03, 0.23)80.17 (0.09, 0.35)0.50 (0.15, 1.64)New dialysis10.02 (0.00, 0.15)30.17 (0.09, 0.35)0.34 (0.04, 3.17)

*Acute kidney injury presence and severity was defined by KDIGO (Kidney Disease: Improving Global Outcomes) classification.

CI, confidence interval; HR, hazard ratio; SCr, serum creatinine.

Conclusion:

These results demonstrate the kidney safety of LD-MTX among patients without advanced CKD at baseline. We observed a possible beneficial effect of LD-MTX on preserving kidney function, suggesting that inflammation may be involved in the pathogenesis of CKD in this population.

Disclosure of Interests:

Jeffrey Sparks Consultant of: Dr. J Sparks has performed consultancy for Bristol-Myers Squibb, Gilead, Inova Diagnostics, Optum, and Pfizer unrelated to this work., Grant/research support from: Dr. J Sparks has received research support from Bristol-Myers Squibb., Kathleen Vanni: None declared, Matthew Sparks: None declared, Chang Xu: None declared, Leah Santacroce: None declared, Robert Glynn Grant/research support from: Dr. Glynn has received grant support unrelated to the present research from AstraZeneca, Kowa, Pfizer, and Novartis., Paul Ridker Consultant of: Dr. Ridker has served as a consultant to Corvidia, Inflazome, and CiviBioPharm., Grant/research support from: Dr. Ridker receives research support unrelated to the present study from Kowa, Novartis, and Amarin., Daniel Solomon Grant/research support from: Dr. Solomon receives research support unrelated to the present study from Abbvie, Amgen, Corrona, Genentech, Janssen, and Pfizer.