A single-index threshold Cox proportional hazard model for identifying a treatment-sensitive subset based on multiple biomarkers

2018 ◽  
Vol 37 (23) ◽  
pp. 3267-3279 ◽  
Author(s):  
Ye He ◽  
Huazhen Lin ◽  
Dongsheng Tu
Keyword(s):  
Hazard Model ◽  
Cox Proportional Hazard Model ◽  
Proportional Hazard ◽  
Proportional Hazard Model ◽  
Single Index ◽  
Cox Proportional Hazard ◽  
Multiple Biomarkers

scholarly journals A Study of Factors Affecting the Length of Hospital Stay of COVID-19 Patients by Cox-Proportional Hazard Model in a South Indian Tertiary Care Hospital

2021 ◽  
Vol 12 ◽  
pp. 215013272110002
Author(s):  
Gayathri Thiruvengadam ◽  
Marappa Lakshmi ◽  
Ravanan Ramanujam
Keyword(s):  
Hospital Stay ◽  
Tertiary Care ◽  
Length Of Hospital Stay ◽  
Hazard Model ◽  
Cox Proportional Hazard Model ◽  
Care Hospital ◽  
Proportional Hazard ◽  
Proportional Hazard Model ◽  
Cox Proportional Hazard ◽  
South Indian

Background: The objective of the study was to identify the factors that alter the length of hospital stay of COVID-19 patients so we have an estimate of the duration of hospitalization of patients. To achieve this, we used a time to event analysis to arrive at factors that could alter the length of hospital stay, aiding in planning additional beds for any future rise in cases. Methods: Information about COVID-19 patients was collected between June and August 2020. The response variable was the time from admission to discharge of patients. Cox proportional hazard model was used to identify the factors that were associated with the length of hospital stay. Results: A total of 730 COVID-19 patients were included, of which 675 (92.5%) recovered and 55 (7.5%) were considered to be right-censored, that is, the patient died or was discharged against medical advice. The median length of hospital stay of COVID-19 patients who were hospitalized was found to be 7 days by the Kaplan Meier curve. The covariates that prolonged the length of hospital stay were found to be abnormalities in oxygen saturation (HR = 0.446, P < .001), neutrophil-lymphocyte ratio (HR = 0.742, P = .003), levels of D-dimer (HR = 0.60, P = .002), lactate dehydrogenase (HR = 0.717, P = .002), and ferritin (HR = 0.763, P = .037). Also, patients who had more than 2 chronic diseases had a significantly longer length of stay (HR = 0.586, P = .008) compared to those with no comorbidities. Conclusion: Factors that are associated with prolonged length of hospital stay of patients need to be considered in planning bed strength on a contingency basis.

scholarly journals SMOKING STATUS AFFECTING SURVIVAL OF ADENOCARCINOMA LUNG CANCER PATIENTS IN KUALA LUMPUR, MALAYSIA

2017 ◽  
Vol 10 (9) ◽  
pp. 312
Author(s):  
Nida Sajid Ali Bangash ◽  
Natasha Hashim ◽  
Nahlah Elkudssiah Ismail
Keyword(s):  
Lung Cancer ◽  
Prognostic Significance ◽  
Hazard Model ◽  
Rank Test ◽  
Cox Proportional Hazard Model ◽  
Proportional Hazard ◽  
Kuala Lumpur ◽  
Proportional Hazard Model ◽  
Cox Proportional Hazard ◽  
Survival Difference

  Objective: Adenocarcinoma (AC) of the lung is now the most common histologic type of non-small cell lung cancer (NSCLC) worldwide since the past 20 years. This study was conducted to investigate survival difference among smoker and non-smoker lung AC patients.Methods: A retrospective observational study was conducted for 81 advanced NSCLC adult Malaysian patients in Radiotherapy and Oncology Clinic at Hospital Kuala Lumpur, Malaysia. A total of adult 30 Malaysian smokers and 51 non-smokers with lung AC were included. Ex-smokers were not included in the study. Demographic and clinical data were collected and described. For survival analysis, Kaplan–Meier test and log-rank test were used to calculate overall survival (OS) and analyse the difference in the survival curve. Cox proportional hazard model was used to identify prognostic significance of smoking status.Results: Non-smokers showed a significant association with female gender and Stage IV NSCLC. The median OS was higher for non-smokers (493 days) as compared to smokers (230 days). The Cox proportional hazard model showed higher hazard ratio for smokers.Conclusion: Non-smoking is an independent positive prognostic factor in lung AC.

scholarly journals Introduction of Two-Dose Mumps-Containing Vaccine into Routine Immunization Schedule in Quzhou, China, Using Cox-Proportional Hazard Model

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Zhiying Yin ◽  
Canjie Zheng ◽  
Quanjun Fang ◽  
Xiaoying Gong ◽  
Guoping Cao ◽  
...  
Keyword(s):  
Hazard Model ◽  
Routine Immunization ◽  
Cox Proportional Hazard Model ◽  
Proportional Hazard ◽  
Immunization Schedule ◽  
Proportional Hazard Model ◽  
Cox Proportional Hazard ◽  
Kaplan Meier ◽  
Routine Immunization Schedule ◽  
Different Doses

Mumps is a vaccine-preventable disease caused by the mumps virus, but the incidence of mumps has increased among the children who were vaccinated with one-dose measles-mumps-rubella (MMR) in recent years. In this study, we analyzed the influence of different doses of mumps-containing vaccine (MuCV) against mumps using Cox-proportional hazard model. We collected 909 mumps cases of children who were born from 2006 to 2010 and vaccinated with different doses of MuCV in Quzhou during 2006-2018, which were all clinically diagnosed. Kaplan-Meier survival methods and Cox-proportional hazard model were used to estimate the hazard probabilities. Kaplan–Meier curves showed that the cumulative hazard of male and female has no difference; lower hazards were detected among those who were vaccinated with two-dose MuCV, born in 2006, and infected after supplementary immunization activities (SIA). Cox-proportional hazard regression suggested that onset after SIA, born in 2006, and vaccinated with two-dose MuCV were protective factors against infection even after adjusting for potential confounding effects. Our study showed that it was necessary to revise the diagnostic criteria of mumps and identify RT-PCR as the standard for mumps diagnosis in China. We suggested that routine immunization schedule should introduce two doses of MMR and prevaccination screening should be performed before booster immunization in vaccinated populations.

Impact of timing of adjuvant chemotherapy initiation on survival in pancreatic adenocarcinoma.

2017 ◽  
Vol 35 (4_suppl) ◽  
pp. 355-355 ◽  
Author(s):  
Sofia Palacio ◽  
Caroline Ripat ◽  
Heather Stuart ◽  
Danny Yakoub ◽  
Nipun B. Merchant
Keyword(s):  
Adjuvant Chemotherapy ◽  
Adjuvant Therapy ◽  
Pancreatic Adenocarcinoma ◽  
Surgical Resection ◽  
Hazard Model ◽  
Disease Stage ◽  
Cox Proportional Hazard Model ◽  
Proportional Hazard ◽  
Proportional Hazard Model ◽  
Cox Proportional Hazard

355 Background: Pancreatic adenocarcinoma (PDAC) is now the third leading cause of cancer death. Surgical resection followed by adjuvant chemotherapy has been the standard of care. Due to the significant risk of morbidity following pancreatic surgery, initiation of adjuvant chemotherapy is often delayed. Prior prospective adjuvant trials have suggested that adjuvant therapy can be initiated as late as 12 weeks without detriment, but data regarding the effectiveness of beginning adjuvant therapy beyond that time remains unknown. Methods: We retrospectivelyreviewed data from the National Cancer Data Base (2004-2014) and included adult patients (pts) with PDAC with pathologic stage I-IIB who underwent surgical resection with curative intent. The primary outcome was overall survival (OS) based on time to adjuvant chemotherapy post-surgery as defined by postoperative weeks. Data were analyzed using Cox proportional hazard model and Kaplan-Meier survival curves. Results: 5279 pts. had surgery alone and 4,537 pts. received adjuvant chemotherapy. The median age was 64 years. 52% were male, 88% were white, 46% were treated at comprehensive community cancer centers. The primary surgical approach was whipple procedure in 61% of pts. 63% pts. received single agent chemotherapy and the mean time from surgery to chemotherapy was 61 days. Adjuvant chemotherapy was associated with improved OS irrespective of disease stage compared to those undergoing surgery alone (median OS for surgery alone 14 months vs adjuvant chemotherapy 21 months, p < 0.001). Cox proportional hazard model controlling for stage, surgical technique, lymph node dissection and margin status revealed improved OS in pts. receiving adjuvant chemotherapy. No significant differences in OS were seen for pts. starting adjuvant chemotherapy at 3, 6, 9, 12, 16, 20 or 24 weeks after surgical resection. Conclusions: Current guidelines recommend initiation of adjuvant chemotherapy prior to 12 weeks after pancreatic resection. Initiating adjuvant chemotherapy even up to six months post-operatively improves OS compared to those undergoing surgery alone. Our data supports the use of adjuvant chemotherapy if indicated regardless of time of surgery.

Sign in / Sign up

Export Citation Format

Share Document