scholarly journals Cox proportion hazard model for patients with hepatitis disease in Iraq

2009 ◽  
Vol 6 (3) ◽  
pp. 612-617
Author(s):  
Baghdad Science Journal

Cox regression model have been used to estimate proportion hazard model for patients with hepatitis disease recorded in Gastrointestinal and Hepatic diseases Hospital in Iraq for (2002 -2005). Data consists of (age, gender, survival time terminal stat). A Kaplan-Meier method has been applied to estimate survival function and hazerd function.

2021 ◽  
pp. 1-8
Author(s):  
Fatma Bugdayci Basal ◽  
Cengiz Karacin ◽  
Irem Bilgetekin ◽  
Omur Berna Oksuzoglu

Introduction: The aim of the study was to evaluate impact of the systemic immune-inflammation index (SII) on prognosis and survival within the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) score groups. Methods: The records of 187 patients with metastatic renal cell carcinoma (RCC) were reviewed retrospectively. The SII was calculated as follows: SII = Neutrophil × Platelet/Lymphocyte. The patients were categorized into 2 groups based on a median SII of 730 (×109 per 1 L) as SII low (<730) and SII high (≥730). The Kaplan-Meier method was used for survival analysis and a Cox regression model was utilized to determine independent predictors of survival. Results: The median age was 61 years (range: 34–86 years). Kaplan-Meier tests revealed significant differences in survival between the SII-low and SII-high levels (27.0 vs. 12.0 months, respectively, p < 0.001). The Cox regression model revealed that SII was an independent prognostic factor. The implementation of the log-rank test in the IMDC groups according to the SII level provided the distinction of survival in the favorable group (SII low 49.0 months vs. SII high 11.0 months, p < 0.001), in the intermediate group (SII low 26.0 vs. SII high 15.0 months, p = 0.007), and in the poor group (SII low 19.0 vs. SII high 6.0 months, p = 0.019). Conclusion: The SII was an independent prognostic factor and provided significant differences in survival for the favorable, intermediate, and poor IMDC groups. Thus, the SII added to the IMDC score may be clinically beneficial in predicting survival.


2021 ◽  
Vol 8 (Supplement_1) ◽  
pp. S378-S379
Author(s):  
Guillermo Rodriguez-Nava ◽  
Goar Egoryan ◽  
Daniela Patricia Trelles-Garcia ◽  
Maria Adriana Yanez-Bello ◽  
Qishuo Zhang ◽  
...  

Abstract Background Growing evidence supports the use of remdesivir and tocilizumab for the treatment of hospitalized patients with severe COVID-19. The purpose of this study was to evaluate the use of remdesivir and tocilizumab for the treatment of severe COVID-19 in a community hospital setting. Methods We used a de-identified dataset of hospitalized adults with severe COVID-19 according to the National Institutes of Health definition (SpO2 &lt; 94% on room air, a PaO2/FiO2 &lt; 300 mm Hg, respiratory frequency &gt; 30/min, or lung infiltrates &gt; 50%) admitted to our community hospital located in Evanston Illinois, between March 1, 2020, and March 1, 2021. We performed a Cox proportional hazards regression model to examine the relationship between the use of remdesivir and tocilizumab and inpatient mortality. To minimize confounders, we adjusted for age, qSOFA score, noninvasive positive-pressure ventilation, invasive mechanical ventilation, and steroids, forcing these variables into the model. We implemented a sensitivity analysis calculating the E-value (with the lower confidence limit) for the obtained point estimates to assess the potential effect of unmeasured confounding. Figure 1. Kaplan–Meier survival curves for in-hospital death among patients treated with and without steroids The hazard ratio was derived from a bivariable Cox regression model. The survival curves were compared with a log-rank test, where a two-sided P value of less than 0.05 was considered statistically significant. Figure 2. Kaplan–Meier survival curves for in-hospital death among patients treated with and without remdesivir The hazard ratio was derived from a bivariable Cox regression model. The survival curves were compared with a log-rank test, where a two-sided P value of less than 0.05 was considered statistically significant. Results A total of 549 patients were included. The median age was 69 years (interquartile range, 59 – 80 years), 333 (59.6%) were male, 231 were White (41.3%), and 235 (42%) were admitted from long-term care facilities. 394 (70.5%) received steroids, 192 (34.3%) received remdesivir, and 49 (8.8%) received tocilizumab. By the cutoff date for data analysis, 389 (69.6%) patients survived, and 170 (30.4%) had died. The bivariable Cox regression models showed decreased hazard of in-hospital death associated with the administration of steroids (Figure 1), remdesivir (Figure 2), and tocilizumab (Figure 3). This association persisted in the multivariable Cox regression controlling for other predictors (Figure 4). The E value for the multivariable Cox regression point estimates and the lower confidence intervals are shown in Table 1. Figure 3. Kaplan–Meier survival curves for in-hospital death among patients treated with and without tocilizumab The hazard ratio was derived from a bivariable Cox regression model. The survival curves were compared with a log-rank test, where a two-sided P value of less than 0.05 was considered statistically significant. Figure 4. Forest plot on effect estimates and confidence intervals for treatments The hazard ratios were derived from a multivariable Cox regression model adjusting for age as a continuous variable, qSOFA score, noninvasive positive-pressure ventilation, and invasive mechanical ventilation. Table 1. Sensitivity analysis of unmeasured confounding using E-values CI, confidence interval. Point estimate from multivariable Cox regression model. The E value is defined as the minimum strength of association on the risk ratio scale that an unmeasured confounder would need to have with both the exposure and the outcome, conditional on the measured covariates, to explain away a specific exposure-outcome association fully: i.e., a confounder not included in the multivariable Cox regression model associated with remdesivir or tocilizumab use and in-hospital death in patients with severe COVID-19 by a hazard ratio of 1.64-fold or 1.54-fold each, respectively, could explain away the lower confidence limit, but weaker confounding could not. Conclusion For patients with severe COVID-19 admitted to our community hospital, the use of steroids, remdesivir, and tocilizumab were significantly associated with a slower progression to in-hospital death while controlling for other predictors included in the models. Disclosures All Authors: No reported disclosures


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
M J Arocena ◽  
G Vanerio

Abstract Background Oral anticoagulants are the cornerstone for the management of atrial fibrillation (AF) to reduce cardioembolic stroke Randomized controlled trials of anticoagulants have shown non-inferiority of direct oral anticoagulants (DOACs) compared to warfarin Most DOACs represent an advance in therapeutic safety when compared to warfarin for prevention of thromboembolism in patients with AF. Objectives Determine long term survival, total mortality rates and mortality cause between patients with non-valvular atrial fibrillation (AF) receiving anticoagulants (warfarin, dabigatran and rivaroxaban) Methods Retrospective analysis of consecutive patients with AF receiving anticoagulants in two Hospitals in Montevideo, using electronic registries. Demographics, co-morbidities, CHA2DS2VASc scores and mortality cause were annotated. Follow-up started on Jan 2011 and finished on Dec 2017. Anticoagulation quality was expressed as the standard deviation of INRs (SD-INRs). We performed global mortality and mortality cause analysis on patients with anti-VitK versus direct anticoagulants. Statistical analysis: Survival analysis was performed using Kaplan-Meier (log rank) and Cox regression model. All differences between groups were considered significant if the p value was <0.001. Results We studied 4501 pts., 3627 patients were on warfarin (80.6%), 456 (10.1%) were on dabigatran and 418 (9.3%) on rivaroxaban. Those receiving direct anticoagulants were older, 79±9 vs 77±11 years, (p=0.0001), 51.3% were female, with a significantly higher prevalence of HTN; 93.7% vs 88.8% and a CHA2DS2VASc score ≥2 (96% vs 91%), and a lower prevalence of CHD (5.8% vs 10.4%), CHF (3.7% vs 9.5%) and CKD (2.3% vs 6.3%).Total mortality was 818 (18%); patients receiving warfarin had significantly higher mortality rates, 727 (20.1%) vs 91 (10.4%); 63 and 28 (13.8%, 6.7% dabigatran and rivaroxaban respectively) Kaplan-Meier curves were significantly different (Figure 1) showing higher survival rates for those on DOACs. The SD-INRs were 0.85±0.47 (n=1726 alive) vs 1.05±0.46 (n=548 dead), mean difference 0.2 (99% CI 0.14–0.26). Mortality could be analysed in 759 patients (92,7%). The most important cause of death was cardiovascular disease in 26.5%. We could not find significant differences in the cause of death between groups. Using Cox regression model, variables with significant increased mortality were HTN, CHD, CHF, CKD and history of previous CVA. The only variable with a significant decrease in mortality was the use of dabigatran or rivaroxaban; HR 0.55 (95% CI 0.44–0.69) Figure 1 Conclusions In this large cohort of patients, those receiving warfarin have significantly higher mortality rates. Mortality differences were not related to stroke or major bleeding but could be explained by a higher prevalence of CHD, CHF and CKD in the warfarin group despite a significant lower CHA2DS2VASc score.


Author(s):  
Rezki Elisafitri ◽  
A. Arsunan Arsin ◽  
Atjo Wahyu

Leukemia Limfoblastik Akut (LLA) merupakan salah satu keganasan hematologi yang paling banyak dideritaoleh anak-anak. Tolak ukur keberhasilan pengobatan pada pasien leukemia dapat dilihat berdasarkan angkakesintasan. Penelitian ini bertujuan mengetahui proporsi kesintasan pasien LLA pada anak di RSUP Dr.WahidinSudirohusodo dan faktor prognosis yang mempengaruhinya. Penelitian ini menggunakan desain studiobservasional analitik dengan rancangan kohort retrospektif. Sampel pada penelitian ini adalah pasien LLA yangdidiagnosis tahun 2014-2017 di RSUP Dr.Wahidin Sudirohusodo. Sebanyak 109 pasien dipilih secara simplerandom sampling. Data penelitian dikumpulkan dengan melakukan penelusuran rekam medik pasien. Datadianalisis menggunakan analisis Kaplan-Meier dan Cox Regression. Hasil penelitian menunjukkan bahwaproporsi kesintasan 48 bulan pasien LLA pada anak di RSUP Dr. Wahidin Sudirohusodo Makassar sebesar 26%.Faktor prognosis yang berhubungan secara statistik dengan kesintasan pasien LLA adalah status gizi (p=0,028),sedangkan umur dan jenis kelamin tidak berhubungan dengan kesintasan pasien LLA (p>0,05). Berdasarkananalisis multivariat dengan cox regression model interaksi, faktor prognosis yang paling berpengaruh terhadapkesintasan pasien LLA adalah status gizi (p=0,040; HR=1,739 CI 95% 1,024-2,952). Pasien LLA dengan statusgizi abnormal memiliki risiko kematian 1,739 kali lebih tinggi dibandingkan pasien LLA dengan status gizinormal.


2021 ◽  
Vol 50 (Supplement_1) ◽  
Author(s):  
Yangyang Liu ◽  
Jingjing Zhang ◽  
Toshiharu Mitsuhashi ◽  
Toshihiko Matsuo ◽  
Takashi Yorifuji ◽  
...  

Abstract Background Many previous methodological studies suggested to use age as time scale in Cox regression model, and some statistical analyses directly applied this conclusion. In the present study, we explain why age is not a more appropriate time scale compared to the time-on-study time scale. Methods We address this argument based on five aspects: Cox regression model, conditional likelihood estimation, dataset of left-truncation or right-censoring, algorithms and software for Cox model, and inferring survival function. Furthermore, logical and algorithmic errors arise in the procedure of parameter inference with age time scale, and that certain evaluation indicators proposed by previous studies are inappropriate. Results The function of time scale is mainly a sampling method for maximum likelihood estimation to infer coefficient of Cox regression model, and the method defined by the age time scale is incorrect in logics and algorithms. Furthermore, age as time scale creates new problems, such as the omission of covariates, loss of information as a continuous variable, increase in dropout, and inability to obtain the survival function. Conclusions For the Cox regression model, the classic time-on-study time scale is more appropriate compared to age as time scale. Key messages It is an important discussion because using age as time scale was first proposed decades ago, meaning that lots of turnovers in researchers, newbies tend to accept the assumptions of their predecessors, but the suitability has never been rigorously verified.


2009 ◽  
Vol 53 (11) ◽  
pp. 4772-4777 ◽  
Author(s):  
Juan C. Martínez-Pastor ◽  
Ernesto Muñoz-Mahamud ◽  
Félix Vilchez ◽  
Sebastián García-Ramiro ◽  
Guillem Bori ◽  
...  

ABSTRACT The aim of our study was to evaluate the outcome of acute prosthetic joint infections (PJIs) due to gram-negative bacilli (GNB) treated without implant removal. Patients with an acute PJI due to GNB diagnosed from 2000 to 2007 were prospectively registered. Demographics, comorbidity, type of implant, microbiology data, surgical treatment, antimicrobial therapy, and outcome were recorded. Classification and regression tree analysis, the Kaplan-Meier survival method, and the Cox regression model were applied. Forty-seven patients were included. The mean age was 70.7 years, and there were 15 hip prostheses and 32 knee prostheses. The median number of days from the time of arthroplasty was 20. The most frequent pathogens were members of the Enterobacteriaceae family in 41 cases and Pseudomonas spp. in 20 cases. Among the Enterobacteriaceae, 14 were resistant to ciprofloxacin, while all Pseudomonas aeruginosa isolates were susceptible to ciprofloxacin. The median durations of intravenous and oral antibiotic treatment were 14 and 64 days, respectively. A total of 35 (74.5%) patients were in remission after a median follow-up of 463 days (interquartile range, 344 to 704) days. By use of the Kaplan-Meier survival curve, a C-reactive protein (CRP) concentration of ≤15 mg/dl (P = 0.03) and receipt of a fluoroquinolone, when all GNB isolated were susceptible (P = 0.0009), were associated with a better outcome. By use of a Cox regression model, a CRP concentration of ≤15 mg/dl (odds ratio [OR], 3.57; 95% confidence interval [CI], 1.05 to 12.5; P = 0.043) and receipt of a fluoroquinolone (OR, 9.09; 95% CI, 1.96 to 50; P = 0.005) were independently associated with better outcomes. Open debridement without removal of the implant had a success rate of 74.5%, and the factors associated with good prognosis were a CRP concentration at the time of diagnosis ≤15 mg/dl and treatment with a fluoroquinolone.


2020 ◽  
Vol 16 (6) ◽  
pp. 209-217
Author(s):  
Huijun Chen ◽  
Shenghua Song ◽  
Liqing Zhang ◽  
Weida Dong ◽  
Xi Chen ◽  
...  

Aim: To evaluate the impact of preoperative platelet–lymphocyte ratio (PLR), neutrophil–lymphocyte ratio (NLR), derived NLR (dNLR) and lymphocyte–monocyte ratio (LMR) on the prognosis of laryngeal squamous cell carcinoma. Materials & methods: Overall survival and recurrence-free survival (RFS) were analyzed using Kaplan–Meier estimates. Multivariable Cox regression model was used to evaluate the independent prognostic significance of variables. Results: High PLR (>103.96), NLR (>1.96) and dNLR (>1.70) predicted lower RFS according to Kaplan–Meier method. In COX regression model, patients with high PLR had poor RFS estimates compared with those with lower PLR (p < 0.001). Conclusion: Preoperative PLR was a more valuable prognostic factor than NLR, dNLR and LMR for the recurrence of laryngeal squamous cell carcinoma.


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