scholarly journals 813. The Reduction of the acquisition rate of carbapenem resistant Acinetobacter baumannii after room privatization in the intensive care unit

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S448-S449
Author(s):  
Jongtak Jung ◽  
Pyoeng Gyun Choe ◽  
Chang Kyung Kang ◽  
Kyung Ho Song ◽  
Wan Beom Park ◽  
...  
Keyword(s):  
Regression Model ◽  
Acinetobacter Baumannii ◽  
Cox Regression ◽  
Univariate Analysis ◽  
Intervention Group ◽  
Feeding Tube ◽  
Control Group ◽  
Cox Regression Model ◽  
Carbapenem Resistant ◽  
Hospital Acquired

Abstract Background Acinetobacter baumannii is one of the major pathogens of hospital-acquired infection recently and hospital outbreaks have been reported worldwide. On September 2017, New intensive care unit(ICU) with only single rooms, remodeling from old ICU with multibed bay rooms, was opened in an acute-care tertiary hospital in Seoul, Korea. We investigated the effect of room privatization in the ICU on the acquisition of carbapenem-resistant Acinetobacter baumannii(CRAB). Methods We retrospectively reviewed medical records of patients who admitted to the medical ICU in a tertiary care university-affiliated 1,800-bed hospital from 1 January 2015 to 1 January 2019. Patients admitted to the medical ICU before the remodeling of the ICU were designated as the control group, and those who admitted to the medical ICU after the remodeling were designated as the intervention group. Then we compared the acquisition rate of CRAB between the control and intervention groups. Patients colonized with CRAB or patients with CRAB identified in screening tests were excluded from the study population. The multivariable Cox regression model was performed using variables with p-values of less than 0.1 in the univariate analysis. Results A total of 1,105 cases admitted to the ICU during the study period were analyzed. CRAB was isolated from 110 cases in the control group(n=687), and 16 cases in the intervention group(n=418). In univariate analysis, room privatization, prior exposure to antibiotics (carbapenem, vancomycin, fluoroquinolone), mechanical ventilation, central venous catheter, tracheostomy, the presence of feeding tube(Levin tube or percutaneous gastrostomy) and the length of ICU stay were significant risk factors for the acquisition of CRAB (p< 0.05). In the multivariable Cox regression model, the presence of feeding tube(Hazard ratio(HR) 4.815, 95% Confidence interval(CI) 1.94-11.96, p=0.001) and room privatization(HR 0.024, 95% CI 0.127-0.396, p=0.000) were independent risk factors. Table 1. Univariate analysis of Carbapenem-resistant Acinetobacter baumannii Table 2. Multivariable Cox regression model of the acquisition of Carbapenem-resistant Acinetobacter baumannii Conclusion In the present study, room privatization of the ICU was correlated with the reduction of CRAB acquisition independently. Remodeling of the ICU to the single room would be an efficient strategy for preventing the spreading of multidrug-resistant organisms and hospital-acquired infection. Disclosures All Authors: No reported disclosures

scholarly journals An Investigation Into the Beneficial Effects of High-Dose Interferon beta 1-a, Compared to Low-Dose Interferon Beta 1-a (the base therapeutic regimen) in moderate to severe COVID-19

2021 ◽  
Author(s):  
Ilad Alavi Darazam ◽  
Firouze Hatami ◽  
Mohammad Mahdi Rabiei ◽  
Mohamad Amin Pourhoseingholi ◽  
Minoosh Shabani ◽  
...  
Keyword(s):  
Regression Model ◽  
Low Dose ◽  
Interferon Beta ◽  
Cox Regression ◽  
Intervention Group ◽  
Control Group ◽  
P Value ◽  
High Dose ◽  
Cox Regression Model ◽  
Subcutaneous Injections

Abstract Introduction: Coronavirus disease 2019 (COVID-19) has been a serious obstacle in front of public health. Interferon-beta 1a (IFN-β 1a) has been used to treat patients with COVID-19. We aimed to compare the effectiveness of high dose IFN-β 1a compared to low dose IFN-β 1a (the base therapeutic regimen) in moderate to severe COVID-19 cases.Methods: In this randomized, controlled, and clinical trial, eligible patients with confirmed SARS-CoV-2 infections were randomly assigned to receive one of the two following therapeutic regimens: The intervention group was treated with high dose IFN-β 1a (Recigen) (Subcutaneous injections of 88μg (24,000 IU) on days 1, 3, 6) + lopinavir /ritonavir (Kaletra) and the control group was treated with low dose IFN-β 1a (Recigen) (Subcutaneous injections of 44μg (12,000 IU) on days 1, 3, 6) + lopinavir /ritonavir (Kaletra) (400mg/100 mg twice a day for 10 days, orally, in all two groups). Result:A total of 168 COVID- 19 confirmed patients underwent randomization; 83 were assigned to the intervention group and 85 were assigned to the control group. Median Time To Clinical Improvement (TTIC) for cases treated with low dose of IFN-β1a was shorter than that for cases treated with high dose of IFN-β1a (6 vs10 days; P=0.018). Hazard Ratio for TTCI in the Cox regression model was 1.56 (95% CI: 1.05-2.30, P-value=0.026). Due to differences between some baseline clinical factors between intervention and control group, we; therefore, performed an adjusted analysis by including spo2, D-dimer and CRP in Cox regression model. The model failed to reach a significant difference between two groups. The adjusted HR was 1.37 (95% CI: 0.88-2.12, P-value=0.16). No difference was observed in terms of mortality between two groups. ConclusionThe use of high-dose IFN-β 1a did not improve TTCI in hospitalized patients with moderate to severe COVID-19. Also, it has not any significant effect in mortality reduction compared with treating with low-dose IFN-β 1a.Trial registration: The trial was confirmed by the Ethics in Medical Research Committee of the Shahid Beheshti University of Medical Sciences. signed informed consents were obtained from all the participants or their legally authorized representatives. This trial has been registered as ClinicalTrials.gov, NCT04521400.

scholarly journals Serum miRNAs, a potential prognosis marker of loco-regionally advanced nasopharyngeal carcinoma patients treated with CCRT

2019 ◽  
Author(s):  
Zhimin Zhang ◽  
Ge Wang ◽  
Feng Jin ◽  
Jijun Zheng ◽  
He Xiao ◽  
...  
Keyword(s):  
Regression Model ◽  
Distant Metastasis ◽  
Clinical Remission ◽  
Cox Regression ◽  
Rank Test ◽  
Control Group ◽  
Cox Regression Model ◽  
Serum Mirnas ◽  
Significant Difference ◽  
Before And After

Abstract Background: Serum miRNA was once found as potential disease survival index,thus we investigated the role of miRNA in predicting prognosis in loco-regionally advanced NPC patients treated with CCRT. Methods: This study included two phases: (i) We enrolled 3 NPC patients with recurrence or distant metastasis (experimental group, EG) and 3 NPC patients in clinical remission (control group, CG) , who were treated with CCRT within 5 years.The paired serum was collected before and after treatment and biomarkers were discovered by TaqMan Human MicroRNA Arrays. (ii) we used the bioinformatic analysis, marker selection and an independent validation by qRT-PCR to analyse the serums of 29 NPC patients with recurrent disease or distant metastasis and 19 NPC patients in clinical remission treated with CCRT. We used the Kaplan-Meier method, log-rank test and Cox regression model to estimate the accuracy of the miRNAs to predict PFS and OS, and identified factors significantly associated with prognosis, respectively. Results: Using fold change≥2.0 or ≤0.5 and p≤0.05 as cutoff levels, we identified 1 up-regulated and 9 down-regulated miRNAs, 1 up-regulated and 6 down-regulated miRNAs in EG versus CG before and after CCRT, respectively. After significantly down-regulated miRNAs from EG versus CG were removed, only 9 different miRNAs were significantly reduced. In the serum samples of 48 NPC patients, there were no significant difference in the expression of miRNA-26b, miRNA-29a and miRNA-125b before CCRT, and the expression of miRNA-143 and miRNA-29b after CCRT. We calculated a risk score with the expression of miRNA-26b、miRNA-29a、miRNA-125b、miRNA-29b、miRNA-143 and then classified patients as high or low risk group. Cox regression model suggested that combining miRNA-29a and miRNA-125b before CCRT with miRNA-26b after CCRT was independent prognostic factors for PFS (HR=3.149, 95%CI:1.018-9.115, p=0.034), whereas combining the former two is independent for OS (HR=5.146, 95%CI:1.674-15.817, p=004）. Conclusions: For loco-regionally advanced NPC patients treated with CCRT, especially high-risk patients- serum miRNAs such as miRNA-29a, miRNA-125b and miRNA-26b etc, play an important role in predicting prognosis factors for PFS and OS, which will contribute to the strategic direction of future research.

scholarly journals Impact of Non-synchronous Diagnostic Ureteroscopy on Intravesical Recurrence in Patients Underwent Radical Nephroureterectomy for Upper Tract Urothelial Carcinoma: A Propensity-Score Matched Analysis

2019 ◽  
Author(s):  
Huamao Ye ◽  
Xiang Feng ◽  
Yang Wang ◽  
Rui Chen ◽  
Meimian Hua ◽  
...  
Keyword(s):  
Propensity Score ◽  
Regression Model ◽  
Urothelial Carcinoma ◽  
Cox Regression ◽  
Upper Tract Urothelial Carcinoma ◽  
Control Group ◽  
Radical Nephroureterectomy ◽  
Cox Regression Model ◽  
Upper Tract ◽  
The Impact

Abstract Background: The effect of diagnostic ureteroscopy (DURS) on intravesical recurrence (IVR) after radical nephroureterectomy (RNU) were controversial. To investigate the impact of DURS, we carried out this single-center retrospective study by applying propensity-score matching (PSM) and Cox regression model. Patients and Methods: The data of 160 patients with pTa-pT3 upper tract urothelial carcinoma (UTUC) were analyzed. Eighty-six patients underwent DURS (DURS group) and 74 patients without DURS (control group). The DURS group was further sub-grouped into synchronous DURS group (DURS followed by immediate RNU, n=45) and non-synchronous DURS group (DURS followed by delayed RNU, n=41). Baseline confounders were corrected by PSM. The impact of DURS on IVR was assessed by Kaplan-Meier analysis in PSM cohort and by Cox regression model in the full data set. Results: The median follow-up time was 40.4 months. No difference of the 3-year IVRFS between DURS group and control group (72.6% vs. 65.3%, p=0.263). In subgroup analysis, the 3-year IVR-free survival of non-synchronous DURS group (51.4%) was significantly lower than that of synchronous DURS (78.3%) or control group (72.6%) (p=0.027). Further Cox regression analysis showed that non-synchronous DURS (HR 1.481, 95% CI 1.031-2.127, p=0.034) was independent risk factors for postoperative IVR. Conclusions: Non-synchronous DURS was not recommended for the diagnosis and preoperative evaluation of UTUC, because it could raise the risk of IVR after RNU. For UTUC patients in need of DURS, synchronous DURS could be a safer choice than the non-synchronous DURS in terms of lowering the IVR risk.

Prognostic Significance of Elevated Endothelin-1 Levels in Patients with Colorectal Cancer

2004 ◽  
Vol 19 (1) ◽  
pp. 32-37 ◽  
Author(s):  
C. Arun ◽  
N.J.M. London ◽  
D.M. Hemingway
Keyword(s):  
Colorectal Cancer ◽  
Overall Survival ◽  
High Risk ◽  
Adjuvant Therapy ◽  
Regression Model ◽  
Cox Regression ◽  
Univariate Analysis ◽  
Prognostic Significance ◽  
Cox Regression Model ◽  
Endothelin 1

Background Prognostic factors from clinical, laboratory and pathological data of patients with colorectal cancer are essential to identify high-risk groups to whom beneficial adjuvant therapy could be given. Endothelin-1, a growth factor, has been associated with the development and spread of solid tumours. This prospective study was performed to determine whether preoperative plasma big ET-1 levels might be useful as a prognostic indicator in patients with colorectal carcinoma. Method Sixty-five consecutive patients with colorectal cancer confirmed by biopsy were included prospectively into this study over a 12-month period. Plasma samples from a peripheral vein were obtained prior to surgery. Univariate analysis of survival using age (< or > 70 years), sex, Dukes’ stage (A&B versus C), tumour size (< or > 50 mm), vascular invasion and plasma big ET-1 levels was performed and significant factors were then analysed with the Cox regression model. Results Three variables, age, Dukes’ tumour stage and plasma big ET-1 levels, were found to have prognostic significance (p<0.05). Factors associated with a poorer prognosis were age >70 years (p=0.02), Dukes’ C tumours (p=0.04) and plasma big ET-1 levels >4.2 pg/mL (p=0.02). The Cox regression model identified the same three variables as having independent prognostic value for overall survival. Conclusion Preoperative plasma big ET-1 levels may be useful in predicting overall survival in patients with colorectal cancer. Plasma big ET-1 levels may be useful in the selection of high-risk lymph node-negative patients with colorectal cancer for adjuvant therapy.

scholarly journals Risk of tumor recurrence in intracranial meningiomas: comparative analyses of the predictive value of the postoperative tumor volume and the Simpson classification

2020 ◽  
pp. 1-8 ◽  
Author(s):  
Dorothee Cäcilia Spille ◽  
Katharina Hess ◽  
Eike Bormann ◽  
Cristina Sauerland ◽  
Caroline Brokinkel ◽  
...  
Keyword(s):  
Regression Model ◽  
Predictive Value ◽  
Tumor Volume ◽  
Cox Regression ◽  
Univariate Analysis ◽  
Residual Tumor ◽  
Intracranial Meningioma ◽  
Cox Regression Model ◽  
Postoperative Imaging ◽  
Simpson Grade

OBJECTIVEIn meningiomas, the Simpson grading system is applied to estimate the risk of postoperative recurrence, but might suffer from bias and limited overview of the resection cavity. In contrast, the value of the postoperative tumor volume as an objective predictor of recurrence is largely unexplored. The objective of this study was to compare the predictive value of residual tumor volume with the intraoperatively assessed extent of resection (EOR).METHODSThe Simpson grade was determined in 939 patients after surgery for initially diagnosed intracranial meningioma. Tumor volume was measured on initial postoperative MRI within 6 months after surgery. Correlation between both variables and recurrence was compared using a tree-structured Cox regression model.RESULTSRecurrence correlated with Simpson grading (p = 0.003). In 423 patients (45%) with available imaging, residual tumor volume covered a broad range (0–78.5 cm3). MRI revealed tumor remnants in 8% after gross-total resection (Simpson grade I–III, range 0.12–33.5 cm3) with a Cohen’s kappa coefficient of 0.7153. Postoperative tumor volume was correlated with recurrence in univariate analysis (HR 1.05 per cm3, 95% CI 1.02–1.08 per cm3, p < 0.001). A tree-structured Cox regression model revealed any postoperative tumor volume > 0 cm3 as a critical cutoff value for the prediction of relapse. Multivariate analysis confirmed the postoperative tumor volume (HR 1.05, p < 0.001) but not the Simpson grading (p = 0.398) as a predictor for recurrence.CONCLUSIONSEOR according to Simpson grading was overrated in 8% of tumors compared to postoperative imaging. Because the predictive value of postoperative imaging is superior to the Simpson grade, any residual tumor should be carefully considered during postoperative care of meningioma patients.

scholarly journals Serum miRNAs, a potential prognosis marker of loco-regionally advanced nasopharyngeal carcinoma patients treated with CCRT

2019 ◽  
Author(s):  
Zhimin Zhang ◽  
jiangbiao Huang ◽  
Ge Wang ◽  
Feng Jin ◽  
Jijun Zheng ◽  
...  
Keyword(s):  
Regression Model ◽  
Distant Metastasis ◽  
Clinical Remission ◽  
Cox Regression ◽  
Rank Test ◽  
Control Group ◽  
Cox Regression Model ◽  
Serum Mirnas ◽  
Significant Difference ◽  
Before And After

Abstract Background: Serum miRNA was once found as potential disease survival index,thus we investigated the role of miRNA in predicting prognosis in loco-regionally advanced NPC patients treated with CCRT. Methods: This study included two phases: (i) We enrolled 3 NPC patients with recurrence or distant metastasis (experimental group, EG) and 3 NPC patients in clinical remission (control group, CG),who were treated with CCRT within 5 years.The paired serum was collected before and after treatment and biomarkers were discovered by LNA-TaqMan Human MicroRNA Arrays. (ii) we used the bioinformatic analysis, marker selection and an independent validation by qRT-PCR to analyse the serums of 29 NPC patients with recurrent disease or distant metastasis and 19 NPC patients in clinical remission treated with CCRT. Using the Kaplan-Meier method, log-rank test and Cox regression model to estimate the accuracy of the miRNAs to predict PFS and OS, and identified factors significantly associated with prognosis, respectively. Results: Using fold change≥2.0 or ≤0.5 and p≤0.05 as cutoff levels, we identified 1 up-regulated and 6 down-regulated miRNAs, 1 up-regulated and 9 down-regulated miRNAs in EG versus CG before and after CCRT, respectively. After these down-regulated miRNAs were dealed with bioinformatics analysis and normalization, only 5 different miRNAs were significantly reduced, which there were no significant difference in the expression of miRNA-26b, miRNA-29a and miRNA-125b before CCRT, and the expression of miRNA-143 and miRNA-29b after CCRT in the serum samples of 48 NPC patients. Based on this, we calculated a risk score with the expression of miRNA-26b、miRNA-29a、miRNA-125b、miRNA-29b、miRNA-143 and then classified patients as high or low risk group. Cox regression model suggested that combining miRNA-29a and miRNA-125b before CCRT with miRNA-26b after CCRT was independent prognostic factors for PFS (HR=3.149, 95%CI:1.018-9.115, p=0.034), whereas combining the former two is independent for OS (HR=5.146, 95%CI:1.674-15.817, p=0.04). Conclusions : For loco-regionally advanced NPC patients treated with CCRT, especially high-risk patients- serum miRNAs, such as miRNA-29a, miRNA-125b and miRNA-26b etc., play an important role in predicting prognosis factors of PFS and OS, which will contribute to the strategic direction for future research.

scholarly journals Testing the proportional hazards assumption in cox regression and dealing with possible non-proportionality in total joint arthroplasty research: methodological perspectives and review

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ilari Kuitunen ◽  
Ville T. Ponkilainen ◽  
Mikko M. Uimonen ◽  
Antti Eskelinen ◽  
Aleksi Reito
Keyword(s):  
Survival Analysis ◽  
Regression Model ◽  
Total Joint Arthroplasty ◽  
Full Text ◽  
Proportional Hazards ◽  
Cox Regression ◽  
Joint Arthroplasty ◽  
Central Research ◽  
Cox Regression Model ◽  
Pubmed Database

Abstract Background Survival analysis and effect of covariates on survival time is a central research interest. Cox proportional hazards regression remains as a gold standard in the survival analysis. The Cox model relies on the assumption of proportional hazards (PH) across different covariates. PH assumptions should be assessed and handled if violated. Our aim was to investigate the reporting of the Cox regression model details and testing of the PH assumption in survival analysis in total joint arthroplasty (TJA) studies. Methods We conducted a review in the PubMed database on 28th August 2019. A total of 1154 studies were identified. The abstracts of these studies were screened for words “cox and “hazard*” and if either was found the abstract was read. The abstract had to fulfill the following criteria to be included in the full-text phase: topic was knee or hip TJA surgery; survival analysis was used, and hazard ratio reported. If all the presented criteria were met, the full-text version of the article was then read. The full-text was included if Cox method was used to analyze TJA survival. After accessing the full-texts 318 articles were included in final analysis. Results The PH assumption was mentioned in 114 of the included studies (36%). KM analysis was used in 281 (88%) studies and the KM curves were presented graphically in 243 of these (87%). In 110 (45%) studies, the KM survival curves crossed in at least one of the presented figures. The most common way to test the PH assumption was to inspect the log-minus-log plots (n = 59). The time-axis division method was the most used corrected model (n = 30) in cox analysis. Of the 318 included studies only 63 (20%) met the following criteria: PH assumption mentioned, PH assumption tested, testing method of the PH assumption named, the result of the testing mentioned, and the Cox regression model corrected, if required. Conclusions Reporting and testing of the PH assumption and dealing with non-proportionality in hip and knee TJA studies was limited. More awareness and education regarding the assumptions behind the used statistical models among researchers, reviewers and editors are needed to improve the quality of TJA research. This could be achieved by better collaboration with methodologists and statisticians and introducing more specific reporting guidelines for TJA studies. Neglecting obvious non-proportionality undermines the overall research efforts since causes of non-proportionality, such as possible underlying pathomechanisms, are not considered and discussed.

scholarly journals FRI0181 ORGAN DAMAGE FREE SURVIVAL IN SOUTHERN CHINESE PATIENTS WITH ACTIVE LUPUS NEPHRITIS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 674.1-674
Author(s):  
C. C. Mok ◽  
C. S. Sin ◽  
K. C. Hau ◽  
T. H. Kwan
Keyword(s):  
Lupus Nephritis ◽  
Regression Model ◽  
Cox Regression ◽  
Organ Damage ◽  
Renal Survival ◽  
Cox Regression Model ◽  
Free Survival ◽  
Renal Response

Background:The goals of treatment of lupus nephritis (LN) are to induce remission, retard the progression of chronic kidney disease, prevent organ complications and ultimately reduce mortality. Previous cohort studies of LN have mainly focused on the risk of mortality and development of end stage renal failure (ESRF) (renal survival). The cumulative frequency of LN patients who survive without organ damage, which correlates better with the balance between treatment efficacy and toxicity, as well as quality of life, has not been well studied.Objectives:To study the organ damage free survival and its predictive factors in patients with active LN.Methods:Consecutive patients who fulfilled ≥4 ACR/SLICC criteria for SLE and with biopsy proven active LN between 2003 and 2018 were retrospectivey analyzed. Those with organ damage before LN onset were excluded. Data on renal parameters and treatment regimens were collected. Complete renal response (CR) was defined as normalization of serum creatinine (SCr), urine P/Cr (uPCR) <0.5 and inactive urinary sediments. Partial renal response (PR) was defined as ≥50% reduction in uPCR and <25% increase in SCr. Organ damage of SLE was assessed by the ACR/SLICC damage index (SDI). The cumulative risk of having any organ damage or mortality since LN was studied by Kaplan-Meier’s analysis. Factors associated with a poor outcome were studied by a forward stepwise Cox regression model, with entry of covariates with p<0.05 and removal with p>0.10.Results:273 LN patients were identified but 64 were excluded (organ damage before LN onset). 211 LN patients were studied (92% women; age at SLE 30.4±13.5 years; SLE duration at LN 1.9±3.1years). 47 (22%) patients had nephrotic syndrome and 60 (29%) were hypertensive. Histological LN classes was: III/IV±V (75.1%), I/II (7.8%) and pure V (17.1%) (histologic activity and chronicity score 7.0±4.2 and 1.8±1.5, respectively). Induction regimens were: prednisolone (33.1±17.5mg/day) in combination with intravenous cyclophosphamide (CYC) (21.4%; 1.0±0.2g per pulse), oral CYC (8.6%; 96.4±37.8mg/day), azathioprine (AZA) (14.3%; 78.6±25.2mg/day), mycophenolate mofetil (MMF) (22.8%; 1.9±0.43g/day) and tacrolimus (TAC) (17.1%; 4.3±1.1mg/day). After a follow-up of 8.6±5.4 years, 94(45%) patient developed organ damage (SDI≥1) and 21(10%) patients died. The commonest organ damage was renal (36.3%) and musculoskeletal (17.9%), and the causes of death were: infection (38.1%), malignancy (19.0%), cardiovascular events (9.5%) and ESRF complications (9.5%). At last visit, 114 (55%) patients survived without any organ damage. The cumulative organ damage free survival at 5, 10 and 15 years after renal biopsy was 73.5%, 59.6% and 48.3%, respectively. The 5, 10 and 15-year renal survival rate were 95.2%, 92.0% and 84.1% respectively. In a Cox regression model, nephritic relapse (HR 3.72[1.78-7.77]), proteinuric relapse (HR 2.30[1.07-4.95]) and older age (HR 1.89[1.05-3.37]) were associated with either organ damage or mortality, whereas CR (HR 0.25[0.12-0.50]) at month 12 were associated with organ damage free survival. Baseline SCr, uPCR and histological LN classes were not significantly associated with a poor outcome. Among patients with class III/IV LN, the long-term organ damage free survival were not significantly different in users of MMF (reference) from CYC (IV/oral) (HR 1.45[0.76- 2.75]) or TAC (HR 1.03[0.26-1.62]) as induction therapy.Conclusion:Organ damage free survival is achieved in 55% of patients with active LN upon 9 years of follow-up. CYC/MMF/TAC based induction regimens did not differ for the long-term outcome of LN. Targeting complete renal response and preventing renal relapses remain important goals of LN treatment.Acknowledgments:NILDisclosure of Interests:None declared

The effect of censoring on a multivariate cox regression model comparing surgical and medical treatment for aortic disease patients

1998 ◽  
Vol 19 (3) ◽  
pp. S78-S79
Author(s):  
Charles Oprian ◽  
Kwan Hur ◽  
William Henderson ◽  
Bharat Thakkar ◽  
Frederick Masoudi ◽  
...  
Keyword(s):  
Medical Treatment ◽  
Regression Model ◽  
Cox Regression ◽  
Aortic Disease ◽  
Cox Regression Model

scholarly journals Cox regression survival analysis with compositional covariates: Application to modelling mortality risk from 24-h physical activity patterns

2019 ◽  
Vol 29 (5) ◽  
pp. 1447-1465 ◽  
Author(s):  
DE McGregor ◽  
J Palarea-Albaladejo ◽  
PM Dall ◽  
K Hron ◽  
SFM Chastin
Keyword(s):  
Public Health ◽  
Physical Activity ◽  
Survival Analysis ◽  
Regression Model ◽  
Cox Regression ◽  
Public Health Problem ◽  
Sitting Time ◽  
Cox Regression Model ◽  
Log Ratio ◽  
Activity Behaviour

Survival analysis is commonly conducted in medical and public health research to assess the association of an exposure or intervention with a hard end outcome such as mortality. The Cox (proportional hazards) regression model is probably the most popular statistical tool used in this context. However, when the exposure includes compositional covariables (that is, variables representing a relative makeup such as a nutritional or physical activity behaviour composition), some basic assumptions of the Cox regression model and associated significance tests are violated. Compositional variables involve an intrinsic interplay between one another which precludes results and conclusions based on considering them in isolation as is ordinarily done. In this work, we introduce a formulation of the Cox regression model in terms of log-ratio coordinates which suitably deals with the constraints of compositional covariates, facilitates the use of common statistical inference methods, and allows for scientifically meaningful interpretations. We illustrate its practical application to a public health problem: the estimation of the mortality hazard associated with the composition of daily activity behaviour (physical activity, sitting time and sleep) using data from the U.S. National Health and Nutrition Examination Survey (NHANES).

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