Identification of Prognostic Factors Related to Survival Time: Cox Proportional Hazards Model

e15213 Background: Until recently, few post-D treatment options existed for mCRPC patients (pts). In pts taken off of first-line D for reasons other than progressive disease (PD), retreatment with D at the time of PD was a commonly used strategy. While several prognostic nomograms have been developed for mCRPC patients, none have exclusively examined prognostic factors in D retreated patients. In the present study, we aimed to characterize baseline clinical factors associated with OS outcomes in D retreated mCRPC pts. Methods: Between 1/2007 and 10/2010, all mCRPC pts seen in the Indiana University Simon Cancer Center oncology clinics were approached for recruitment to the IRB approved biorepository protocol. Participants completed a demographic and clinical questionnaire and provided a blood sample. Only mCRPC pts retreated with D with confirmed dates for D first-line completion, D retreatment, and OS were included in this analysis. At D retreatment, patient age, Gleason Grade (GG), presence of pain, time to progression after first-line D therapy, visceral metastases, ECOG performance status, PSA, and PSA doubling time (PSAdt) were examined by Cox proportional hazards model for significant associations (p < 0.05) with OS outcomes. Results: 30 mCRPC pts retreated with D were identified. Complete data were available on 22 pts which formed the analysis cohort. Demographics included: mean age – 69.1 yrs, Caucasian/African-American – 21/1, median GG 8, 55% pain present at baseline, median time from first-line D – 8.6 mo., 30% visceral mets, ECOG 0/1/2 – 3/17/2, mean baseline PSA – 536 ng/ml, mean baseline PSAdt – 2.7 mo. By Cox proportional hazards model, baseline PSA (p = 0.006) was significantly associated with D-retreatment OS with a trend toward significance in patients with pain at baseline (p = 0.059). No other significant associations were identified. Conclusions: Baseline PSA levels were significantly associated with OS outcomes in mCRPC pts retreated with D. Validation and examination of additional clinical variables is warranted in larger datasets.

Download Full-text

Cox Proportional Hazards Model for Identification of the Prognostic Factors in the Survival of Acute Liver Failure Patients in India

Nepalese Journal of Statistics ◽

10.3126/njs.v2i0.21155 ◽

2018 ◽

Vol 2 ◽

pp. 53-74

Author(s):

Shankar Prasad Khanal ◽

V. Sreenivas ◽

S.K. Acharya

Keyword(s):

Survival Analysis ◽

Prognostic Factors ◽

Liver Failure ◽

Cerebral Edema ◽

Goodness Of Fit ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Hazards Model

Background: Acute Liver Failure (ALF) is a kind of dangerous rare liver injury among all liver diseases. Different statistical methods such as Logistic regression, Kaplan-Meier estimate of survival function followed by Log-rank test and semi-parametric approaches of survival analysis has been applied in order to identify the significant risk factors of ALF patients. In most of the studies, regression models used in this setup has not been evaluated by model assumptions and their goodness of fit tests.Objective: To apply appropriate survival analysis technique to identify the prognostic factors in the survival of ALF patients, to develop prognostic index, and to predict survival probability for different scenario.Materials and Methods: The study is based on the retrospective cohort study design with altogether 1099 ALF patients taken from the liver clinic, All India Institute of Medical Sciences, New Delhi India. Cox regression has been considered as the suitable model for handling this time to event data, and the assumptions of the model, goodness of fit of the model was assessed and survival probabilities were predicted.Results: This study has identified six prognostic factors namely age, prothrombin time, cerebral edema, total serum bilirubin, serum creatinine and etiology for ALF patients. The hazards of mortality [HR: 2.38; 95% C.I.: (1.99, 2.85), p < 0.001] is the highest for cerebral edema among all these prognostic factors. Nearly 9%, 26%, 39%, 50%, 59% and 63% of ALF patients with a PI of 1, 3, 5, 7, 9 and 10 respectively die by 3 days of hospital stay.Conclusion: The developed Cox Proportional Hazards model with six prognostic factors has satisfied the model assumptions and goodness of fit tests. The risk score and the predicted survival probabilities will be immensely helpful to the hepatologists to make a quick decision regarding the likely prognosis of a patient at admission and helpful in triaging the ALF patients for liver transplant.Nepalese Journal of Statistics, Vol. 2, 53-74

Download Full-text

Factors Predicting Survival for Cancer of the Ethmoid Sinus

American Journal of Rhinology ◽

10.1177/194589240201600512 ◽

2002 ◽

Vol 16 (5) ◽

pp. 281-286 ◽

Cited By ~ 26

Author(s):

Neil Bhattacharyya

Keyword(s):

Radiation Therapy ◽

Prognostic Factors ◽

Survival Data ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Ethmoid Sinus ◽

Cox Proportional Hazards Model ◽

T Stage ◽

Hazards Model

Objective The aim of this study was to determine survival and prognostic factors for ethmoid sinus cancer. Methods From the Surveillance, Epidemiology, and End Results database for the time period 1988–1998, all cases of ethmoid sinus malignancy were extracted. Demographic, staging, treatment, and survival data were computed. Survival analysis was conducted with the Kaplan-Meier method. Clinical factors influencing survival were determined with the Cox proportional hazards model. Results After excluding patients with metastatic disease on presentation (8.9%) and patients with missing data for T stage, a total of 180 cases were identified. Average age was 60.2 years. Squamous cell carcinoma was the most common tumor (27.8%), followed by adenocarcinoma (12.8%). Overall mean survival was 57 months (median, 38 months) with a 5-year survival of 40.3%. The percentage of patients presenting with T4 lesions was 45.6%, which had a notably lower mean survival of 38 months (median, 18 months). Only 2.3% of patients had positive nodal disease. Increasing age, T stage, and absence of radiation therapy predicted poorer survival in the multivariate model. Adenocarcinoma, adenoid cystic carcinoma, esthesioneuroblastoma, and melanoma showed more favorable survival than other tumor types. Conclusions T stage and tumor histology are the most important prognostic factors in ethmoid sinus carcinoma. Survival for T4 lesions is markedly worse than survival for T1-T3 lesions. Radiation therapy offers a survival benefit in ethmoid sinus malignancy.

Download Full-text

Longevity of Crown Margin Repairs Using Glass Ionomer Cement: A Retrospective Study

Operative Dentistry ◽

10.2341/20-062-c ◽

2021 ◽

Author(s):

JI Watson ◽

JS Patel ◽

MB Ramya ◽

O Capin ◽

KE Diefenderfer ◽

...

Keyword(s):

Survival Time ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Permanent Teeth ◽

Glass Ionomer Cements ◽

Glass Ionomer ◽

Hazards Model ◽

Tooth Type

Clinical Relevance Repairing defective crown margins can extend the functional life of existing crowns. SUMMARY Objective: The objective of this study was to determine the survival time of crown margin repairs (CMRs) with glass ionomer and resin-modified glass ionomer cements on permanent teeth using electronic dental record (EDR) data. Methods: We queried a database of EDR (axiUm; Exan Group, Coquitlam, BC, Canada) in the Indiana University School of Dentistry (IUSD), Indianapolis, IN, USA, for records of patients who underwent CMRs of permanent teeth at the Graduate Operative Dentistry Clinic. Two examiners developed guidelines for reviewing the records and manually reviewed the clinical notes of patient records to confirm for CMRs. Only records that were confirmed with the presence of CMRs were retained in the final dataset for survival analysis. Survival time was calculated by Kaplan-Meier statistics, and a Cox proportional hazards model was performed to assess the influence of age, gender, and tooth type on survival time (a<0.05). Results: A total of 214 teeth (115 patients) with CMR were evaluated. Patient average age was 69.4 ± 11.7 years old. Posterior teeth accounted for 78.5% (n=168) of teeth treated. CMRs using glass ionomer cements had a 5-year survival rate of 62.9% and an annual failure rate (AFR) of 8.9%. Cox proportional-hazards model revealed that none of the factors examined (age, gender, tooth type) affected time to failure. Conclusion: The results indicate the potential of CMRs for extending the functional life of crowns with defective margins, thus reducing provider and patient burden of replacing an indirect restoration. We recommend future studies with a larger population who received CMR to extend the generalizability of our findings and to determine the influence of factors such as caries risk and severity of defects on survival time.

Download Full-text

Therapeutic effect of cranial radiotherapy with or without anlotinib treatment for lung cancer patients with brain metastasis and non-EGFR/ALK-TKIs indication

10.21203/rs.3.rs-44047/v1 ◽

2020 ◽

Author(s):

Zelai He ◽

Jia Liu ◽

Hongwei Li ◽

Jing Qian ◽

Zhen Cui ◽

...

Keyword(s):

Lung Cancer ◽

Prognostic Factors ◽

Brain Metastasis ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Small Cell ◽

Cox Proportional Hazards Model ◽

Cranial Radiotherapy ◽

Hazards Model

Abstract Background: Cranial radiotherapy (CRT) is the main treatment for lung malignant tumor with brain metastasis (BM) and lacking EGFR/ALK-TKIs indication. For non-small cell lung cancer with BM, anlotinib can improve progression free survival (PFS). We retrospectively analyzed the clinical effects of anlotinib + CRT versus CRT alone.Methods: In patients with lung cancer (adenocarcinoma, squamous carcinoma, or small cell carcinoma) with BM and non-EGFR/ALK-TKIs indication, the overall survival (OS) and PFS of anlotinib + CRT treatment versus CRT treatment alone were separately calculated and compared. The Cox proportional hazards model was used to analyze the independent prognostic factors for intracranial PFS (iPFS) and OS. All confounding factors were adjusted, including age, gender, Karnofsky Performance Status (KPS) score, smoking history, physiological characteristics, T/N stage, histology, metastases, and pathological characteristics. Subgroup analysis for iPFS and OS was performed to assess the effects on BM of treatment pattern.Results: The study included 100 patients with BM at baseline and the follow-up data. Of the 100 patients, 67 patients received CRT treatment alone and 33 patients received CRT + anlotinib treatment. The overall response rates of the CRT + anlotinib group and the CRT alone group were 90.91% and 83.58%, respectively. There was significantly more iPFS in the CRT + anlotinib group compared to CRT alone (median iPFS [miPFS]: 9.0 vs 3.0 months; hazard ratio [HR] 1.59; 95% confidence interval [CI] 1.01-2.52; p = 0.038). The OS, extracranial PFS (ePFS), and systematic PFS (sPFS) of CRT + anlotinib group were longer than those of the CRT alone group, but there was no significant statistical difference (median OS [mOS]: 9.0 vs 7.0 months, HR 1.17, 95% CI 0.74-1.85; median ePFS [mePFS]: 9.0 vs 7.0 months, HR 1.23, 95% CI 0.72-2.11; median sPFS [msPFS]: 7.0 vs 4.0 months, HR 1.37, 95% CI 0.82-2.30). The Cox proportional hazards model analysis revealed that age was an independent prognostic factor of iPFS (HR 1.65, 95% CI 1.05-2.59, p = 0.03). Age (HR 1.74, 95% CI 1.09-2.77, p = 0.02) and KPS score (HR 1.88, 95% CI 1.17-3.01, p = 0.01) were identified as independent prognostic factors of OS. Further subgroup analysis of iPFS showed that when the number of BM in the CRT + anlotinib group was less than or equal to three lesions (≤ 3), the miPFS (12.0 months) was significantly longer than that for CRT alone (> 3) (3.0 months), for CRT alone (≤ 3) (3.0 months), and for CRT + anlotinib (> 3) (7.0 months) (p = 0.014). The OS of the CRT + anlotinib group (≤ 3) (mOS 37.0 months) was much longer than that in CRT alone (> 3) (mOS 6.0 months), CRT alone (≤ 3) (mOS 7.5 months), and CRT + anlotinib (> 3) (mOS 8.5 months) groups, but this difference was not statistically significant (p = 0.051).Conclusion: Anlotinib can improve the survival of patients with lung cancer BM, with better efficacy of a combined treatment of anlotinib + CRT compared to that of CRT alone, especially for the iPFS of patients with BM ≤ 3.

Download Full-text

IMPACT OF IGNORING PROGNOSTIC FACTORS ON THE ESTIMATE OF TREATMENT EFFECT USING COX PROPORTIONAL HAZARDS MODEL.

Transplantation Journal ◽

10.1097/00007890-200607152-02281 ◽

2006 ◽

Vol 82 (Suppl 2) ◽

pp. 823

Author(s):

&NA;

Keyword(s):

Prognostic Factors ◽

Treatment Effect ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Hazards Model

Download Full-text

Risk factors associated with major adverse cardiac and cerebrovascular events following percutaneous coronary intervention: a 10-year follow-up comparing random survival forest and Cox proportional-hazards model

BMC Cardiovascular Disorders ◽

10.1186/s12872-020-01834-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Maryam Farhadian ◽

Sahar Dehdar Karsidani ◽

Azadeh Mozayanimonfared ◽

Hossein Mahjub

Keyword(s):

Proportional Hazards ◽

Proportional Hazards Model ◽

Coronary Intervention ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Hazards Model ◽

Cerebrovascular Events ◽

Long Term Follow Up ◽

Stent Length

Abstract Background Due to the limited number of studies with long term follow-up of patients undergoing Percutaneous Coronary Intervention (PCI), we investigated the occurrence of Major Adverse Cardiac and Cerebrovascular Events (MACCE) during 10 years of follow-up after coronary angioplasty using Random Survival Forest (RSF) and Cox proportional hazards models. Methods The current retrospective cohort study was performed on 220 patients (69 women and 151 men) undergoing coronary angioplasty from March 2009 to March 2012 in Farchshian Medical Center in Hamadan city, Iran. Survival time (month) as the response variable was considered from the date of angioplasty to the main endpoint or the end of the follow-up period (September 2019). To identify the factors influencing the occurrence of MACCE, the performance of Cox and RSF models were investigated in terms of C index, Integrated Brier Score (IBS) and prediction error criteria. Results Ninety-six patients (43.7%) experienced MACCE by the end of the follow-up period, and the median survival time was estimated to be 98 months. Survival decreased from 99% during the first year to 39% at 10 years' follow-up. By applying the Cox model, the predictors were identified as follows: age (HR = 1.03, 95% CI 1.01–1.05), diabetes (HR = 2.17, 95% CI 1.29–3.66), smoking (HR = 2.41, 95% CI 1.46–3.98), and stent length (HR = 1.74, 95% CI 1.11–2.75). The predictive performance was slightly better by the RSF model (IBS of 0.124 vs. 0.135, C index of 0.648 vs. 0.626 and out-of-bag error rate of 0.352 vs. 0.374 for RSF). In addition to age, diabetes, smoking, and stent length, RSF also included coronary artery disease (acute or chronic) and hyperlipidemia as the most important variables. Conclusion Machine-learning prediction models such as RSF showed better performance than the Cox proportional hazards model for the prediction of MACCE during long-term follow-up after PCI.

Download Full-text

Elevated plasma growth and differentiation factor 15 predicts incident anemia in older adults aged 60 years and older

The Journals of Gerontology Series A ◽

10.1093/gerona/glaa324 ◽

2020 ◽

Author(s):

Yuko Yamaguchi ◽

Marta Zampino ◽

Toshiko Tanaka ◽

Stefania Bandinelli ◽

Yusuke Osawa ◽

...

Keyword(s):

Older Adults ◽

Proportional Hazards ◽

Proportional Hazards Model ◽

Cox Proportional Hazards ◽

Cox Proportional Hazards Model ◽

Differentiation Factor ◽

Hazards Model ◽

Increased Risk ◽

The Relationship

Abstract Background Anemia is common in older adults and associated with greater morbidity and mortality. The causes of anemia in older adults have not been completely characterized. Although elevated circulating growth and differentiation factor 15 (GDF-15) has been associated with anemia in older adults, it is not known whether elevated GDF-15 predicts the development of anemia. Methods We examined the relationship between plasma GDF-15 concentrations at baseline in 708 non-anemic adults, aged 60 years and older, with incident anemia during 15 years of follow-up among participants in the Invecchiare in Chianti (InCHIANTI) Study. Results During follow-up, 179 (25.3%) participants developed anemia. The proportion of participants who developed anemia from the lowest to highest quartile of plasma GDF-15 was 12.9%, 20.1%, 21.2%, and 45.8%, respectively. Adults in the highest quartile of plasma GDF-15 had an increased risk of developing anemia (Hazards Ratio 1.15, 95% Confidence Interval 1.09, 1.21, P<.0001) compared to those in the lower three quartiles in a multivariable Cox proportional hazards model adjusting for age, sex, serum iron, soluble transferrin receptor, ferritin, vitamin B12, congestive heart failure, diabetes mellitus, and cancer. Conclusions Circulating GDF-15 is an independent predictor for the development of anemia in older adults.

Download Full-text