Demonstrating the Performance of Accelerated Failure Time Model over Cox-PH Model of Survival Data Analysis with Application to HIV-Infected Patients under HAART

2019 ◽  
Author(s):  
Getnet Begashaw
Keyword(s):  
Marital Status ◽  
Functional Status ◽  
Survival Data ◽  
Logistic Model ◽  
Clinical Stage ◽  
Survival Model ◽  
Cd4 Count ◽  
Cd4 Cells ◽  
Time To Event ◽  
Significant Difference

Abstract Background: Human Immunodeficiency Virus (HIV) is a virus that kills CD4 cells. These CD4 cells are white blood cells that fight infection. CD4 count is like a snapshot of how well our immune system is functioning. Studying the way of CD4+ count over time provides an insight to the disease evolution. Methods: This study was considering the data of HIV/AIDS patients who were undergoing Antiretroviral Therapy in the ART clinic of Menellik II Referral Hospital, Addis Ababa, Ethiopia, during the period 1st January 2014 to 31st December 2017. The data was analyzed in separate survival models i.e non parametric, semi parametric (Cox PH) and parametric survival model (AFT models). For the purpose of model diagnosis cox-snail residual analysis were incorporated. Results: For separate survival model log-logistic model is more appropriate for the survival data than other parametric models. Therefore; functional status and regimen class are significant covariates in determining the hazard function patients. . In the Log-logistic model, among the covariates we have included in the survival model: functional status (working subgroup) and regimen class (all subgroup) were significant at 5% level of significance. But, sex, age, baseCD4, marital status and WHO-clinical stage are not significance at 5% significance level. Using cox-snail residual shows proportionality not satisfied for these WHO stage, regimen class and marital status. Conclusions: Log rank and Wilcoxon tests showed that the significant difference in survival situation among the categorical variables selected for this study sex, marital status, functional status, WHO-clinical stages and regimen class subgroups. But, there was no significant difference in the time-to-event between subgroups of sex, Marital Status and WHO clinical Stage, while, Regimen Class and Functional Status there was a significant difference in the time-to-event between subgroups.

scholarly journals Factors Affect the Survival Status of HIV Infected Patients under ART: The Case of Wolisso Catholic Hospital, Wolisso, Ethiopia, 2016.

2020 ◽  
Author(s):  
Alemayehu Siffir Argawu
Keyword(s):  
Substance Abuse ◽  
Condom Use ◽  
Regression Model ◽  
Functional Status ◽  
Survival Time ◽  
Clinical Stage ◽  
Cd4 Count ◽  
Survival Status ◽  
Risk Of Death ◽  
Significant Difference

Abstract INTRODUCTION: Monitoring the length of survival after diagnosis is, therefore, an important component of the surveillance of AIDS. It provides a basis for evaluating individual prognostic factors. The survival of patients with AIDS may depend on a variety of factors that are socio-demographic and clinical factors. The study is designed to identify factors that affect the survival status of HIV infected patients under ART in Wolisso, Ethiopia. METHODS: This is a retrospective study based on cases of HIV infected patients of age 15 years and above who have started ART from September 2010 to August 2013 and followed until February 30th, 2014. To analyze the data descriptive statistics, univariate and multivariate analyses were used. The descriptive analysis indicates that out of the total of 658 HIV-infected patients, 533(81%) are censored and 125(19%) are uncensored in the study. And, from 125 uncensored patients, 60(9.1%) patients have died and 65(9.9%) are dropped out cases. The overall mean estimated survival time of patients under the study was 33.76(95% CI: 32.6-34.9) months.RESULTS: The Kaplan Meier method was used to estimate the survival time and Cox’s regression model was employed to identify the covariates that have a statistically significant effect on the survival of HIV-infected patients. Based on the log-rank test, there was a significant difference in survival experience between the various categories of gender, marital status, work type, duration of pre-ART, regimen type, functional status, TB type, WHO clinical stage, condom use, and substance abuse (like smoking or alcoholic). And, the multivariate analysis of the Cox regression model gives that CD4 count, functional status, TB type, WHO clinical stage, condom use, and substance abuse are significant risk factors for survival of HIV-infected patients. CONCLUSION: The patients with low CD4 count, WHO stage III or IV, being ambulatory or bedridden, extra-pulmonary, not used condom, and substance abuse were associated with a high risk of death or dropped out the ART of the patients. Therefore, it is recommended that these at-risk patients need careful monitoring to improve their survival times by the concerned bodies.

scholarly journals Incidence and determinants of mortality among HIV infected adult patients on antiretroviral therapy in Ethiopia: A systematic review and Meta-analysis

2020 ◽  
Author(s):  
Habtamu Lijalem ◽  
Shimelash Bitew Workie ◽  
Mohammed Suleiman ◽  
Muluken Gunta Gutulo ◽  
Takele Tadesse
Keyword(s):  
Body Weight ◽  
Medication Adherence ◽  
Antiretroviral Therapy ◽  
Functional Status ◽  
Clinical Stage ◽  
Hemoglobin Level ◽  
Older Age ◽  
Cochrane Library ◽  
Cd4 Cells ◽  
Comprehensive Service

Abstract Background Antiretroviral therapy has been highly associated with reduction in the incidence of mortality in HIV/AIDS patients over time. However, there is a regional variation in the extent of reducing the incidence of mortality in many developing countries including Ethiopia. Hence, this study was conducted to generate summary evidences-based data for incidence of mortality and determinants of mortality. Methods Articles were comprehensively searched on Pub Med, Google Scholar, Cochrane library, Scopus, and DOAJ databases using Boolean operators. A Dersimonian and Laird methods of random effect model was used to estimate incidence and determinants of mortality. Heterogeneity, publication bias and quality of each study were checked. Subgroup analysis was employed. Relevant data from each study were extracted. STATA software version 14 was used for all statistical analysis. Result A total of 21 articles were finally reviewed and analyzed. Incidence of mortality was found to be 5/100-person year of observation (95% CI: 4–5/100pyo). Most of the death (67%) occurred during the first year of HAART initiation. Baseline Advanced WHO clinical stage (PHR (Pooled Hazard Rate) 2.88; 95%CI: 2.2–3.8), low CD4 cells count (PHR 1.88; 95% CI: 1.5–2.4), low body weight (PHR 1.6; 95% CI: 1.2–2.2), low hemoglobin level (PHR 2.4; 95% CI: 1.7–3.4), presence of TB infection (PHR 2.9; 95% CI: 2.13–4.61), non – working functional status (PHR 3.9; 95% CI: 2.8–5.4), bad medication adherence (PHR 4.8; 95% CI: 3.2–7.2), lack of cotrimoxazole preventive therapy (PHR 1.5; 95% CI: 1.2–2.0), being male (PHR 1.4; 95% CI: 1.2–1.8) and older age (PHR 1.2; 95% CI: 1.04–1.41) were significantly associated with increased mortality in this study. Conclusion Incidence of mortality was high particularly early in the course of therapy. Advanced WHO clinical stage, CD4 cells count low body weight, low hemoglobin level presence of TB infection, bad medication adherence older age and non-working functional status were significant determinants of incidence of mortality. Comprehensive service and strict follow up should be given to avert this high rate of mortality.

scholarly journals Incidence and determinants of mortality among HIV infected adult patients on antiretroviral therapy in Ethiopia: A systematic review and Meta-analysis

2020 ◽  
Author(s):  
Shimelash Bitew Workie ◽  
Habtamu Lijalem ◽  
Mohammed Suleiman ◽  
Takele Tadesse Adafrie
Keyword(s):  
Body Weight ◽  
Medication Adherence ◽  
Antiretroviral Therapy ◽  
Functional Status ◽  
Clinical Stage ◽  
Hemoglobin Level ◽  
Older Age ◽  
Cochrane Library ◽  
Cd4 Cells ◽  
Comprehensive Service

Abstract Background Antiretroviral therapy has been highly associated with reduction in the incidence of mortality in HIV/AIDS patients over time. However, there is a regional variation in the extent of reducing the incidence of mortality in many developing countries including Ethiopia. Hence, this study was conducted to generate summary evidences-based data for incidence of mortality and determinants of mortality. Methods Articles were comprehensively searched on Pub Med, Google Scholar, Cochrane library, Scopus, and DOAJ databases using Boolean operators. A Dersimonian and Laird methods of random effect model was used to estimate incidence and determinants of mortality. Heterogeneity, publication bias and quality of each study were checked. Subgroup analysis was employed. Relevant data from each study were extracted. STATA software version 14 was used for all statistical analysis. ResultA total of 21 articles were finally reviewed and analyzed. Incidence of mortality was found to be 5/100-person year of observation (95% CI: 4 – 5/100pyo). Most of the death (67%) occurred during the first year of HAART initiation. Baseline Advanced WHO clinical stage (PHR (Pooled Hazard Rate) 2.88; 95%CI: 2.2 – 3.8), low CD4 cells count (PHR 1.88; 95% CI: 1.5 – 2.4), low body weight (PHR 1.6; 95% CI: 1.2 – 2.2), low hemoglobin level (PHR 2.4; 95% CI: 1.7 – 3.4), presence of TB infection (PHR 2.9; 95% CI: 2.13 – 4.61), non – working functional status (PHR 3.9; 95% CI: 2.8 – 5.4), bad medication adherence (PHR 4.8; 95% CI: 3.2 – 7.2), lack of cotrimoxazole preventive therapy (PHR 1.5; 95% CI: 1.2 – 2.0), being male (PHR 1.4; 95% CI: 1.2 – 1.8) and older age (PHR 1.2; 95% CI: 1.04 – 1.41) were significantly associated with increased mortality in this study. ConclusionIncidence of mortality was high particularly early in the course of therapy. Advanced WHO clinical stage, CD4 cells count low body weight, low hemoglobin level presence of TB infection, bad medication adherence older age and non-working functional status were significant determinants of incidence of mortality. Comprehensive service and strict follow up should be given to avert this high rate of mortality.

scholarly journals PNS293 FITTING AN AIC-BASED AVERAGING SURVIVAL MODEL TO TIME-TO-EVENT DATA – A CASE STUDY USING PUBLISHED OVERALL SURVIVAL DATA

2019 ◽  
Vol 22 ◽  
pp. S813
Author(s):  
J. Meng ◽  
P. Pierzchala ◽  
M. Nikodem ◽  
V. Appah-Gyamenah ◽  
J. Lister
Keyword(s):  
Overall Survival ◽  
Survival Data ◽  
Survival Model ◽  
Event Data ◽  
Time To Event ◽  
Time To Event Data

scholarly journals Survival Advantage Following TAG-72 Antigen-Directed Cancer Surgery in Patients With Colorectal Carcinoma: Proposed Mechanisms of Action

2021 ◽  
Vol 11 ◽  
Author(s):  
Charles L. Hitchcock ◽  
Stephen P. Povoski ◽  
Cathy M. Mojzisik ◽  
Edward W. Martin
Keyword(s):  
Immune Response ◽  
Overall Survival ◽  
Monoclonal Antibodies ◽  
Colorectal Carcinoma ◽  
Survival Data ◽  
Clinical Stage ◽  
Critical Role ◽  
Surgical Removal ◽  
Curative Intent ◽  
Significant Difference

Patients with colorectal carcinoma (CRC) continue to have variable clinical outcomes despite undergoing the same surgical procedure with curative intent and having the same pathologic and clinical stage. This problem suggests the need for better techniques to assess the extent of disease during surgery. We began to address this problem 35 years ago by injecting patients with either primary or recurrent CRC with 125I-labeled murine monoclonal antibodies against the tumor-associated glycoprotein-72 (TAG-72) and using a handheld gamma-detecting probe (HGDP) for intraoperative detection and removal of radioactive, i.e., TAG-72-positive, tissue. Data from these studies demonstrated a significant difference in overall survival data (p < 0.005 or better) when no TAG-72-positive tissue remained compared to when TAG-72-positive tissue remained at the completion of surgery. Recent publications indicate that aberrant glycosylation of mucins and their critical role in suppressing tumor-associated immune response help to explain the cellular mechanisms underlying our results. We propose that monoclonal antibodies to TAG-72 recognize and bind to antigenic epitopes on mucins that suppress the tumor-associated immune response in both the tumor and tumor-draining lymph nodes. Complete surgical removal of all TAG-72-positive tissue serves to reverse the escape phase of immunoediting, allowing a resetting of this response that leads to improved overall survival of the patients with either primary or recurrent CRC. Thus, the status of TAG-72 positivity after resection has a significant impact on patient survival.

THE EMPATHY LEVELS OF WOMEN PLAYING IN BASKETBALL LEAGUES

2020 ◽  
Vol 6 (25) ◽  
pp. 760-768
Author(s):  
Nida Gencer ÖZKAN ◽  
◽  
Tülin ATAN
Keyword(s):  
Marital Status ◽  
Leadership Style ◽  
Female Athletes ◽  
Educational Status ◽  
Basketball Players ◽  
Coaching Behaviors ◽  
Significant Difference ◽  
Women's Basketball ◽  
Coaching Behavior ◽  
And Behavior

The aim of this study was to investigate the basketball players’, active in Turkey Women’s Basketball Super and 1st Leagues, empathy levels according to their marital status, educational status in addition to age and marital status of their coach; and to evaluate leadership characteristics and behavior of their coaches according to athlete’s perception. Another aim was to analyze the relation between empathy levels of the athletes and athletes’ perception of coaching behavior. 264 (age; 24.61±5.53 year) female athletes playing in Turkey Women’s Basketball Super and 1st Leagues participated in this study. Leadership Scale for Sports (LSS)-version of Athletes’ Perception of Coaching Behavior that developed by Chelladurai and Saleh, and adapted by Tiryaki and Toros in 2006 was used as data collection tool. Athletes’ perceptions of leadership style and behavior of their coach were evaluated in five different factors. A five-factor solution with 40 items describing the most salient dimensions of coaching behavior was selected as the most meaningful. Empathy levels of the athletes were determined by using Emphatic Tendency Scale which was developed by Dökmen (1988) and composed of 20 items. Empathy levels of the athletes showed no statistically significant difference in terms of any variable (p>0.05). There was no statistically significant difference in athletes’ perceptions of coaching behaviors in terms of marital status of the athlete and age of their coach (p>0.05). In terms of educational status of athletes and marital status of their coach, there were statistically significant differences in athletes’ perceptions of coaching behaviors (p<0.05 and p<0.01). Positive and meaningful correlation was found between empathy scores of the athletes and training and instruction behavior (r=.172**) and autocratic behavior (r=.154*) of the coach (p<0.05 and p<0.01). Educational status of the athletes and marital status of their coach are influental in athletes’ evaluation of their perceptions of coaching behavior. Empathy levels of the athletes are related to their perceptions of coaching behavior.

Increse of newly - detected in situ cancers in non-palpable breast lesions

2006 ◽  
Vol 53 (1) ◽  
pp. 73-75
Author(s):  
N. Miletic ◽  
D. Stojiljkovic ◽  
M. Inic ◽  
M. Prekajski ◽  
A. Celebic ◽  
...  
Keyword(s):  
Breast Tissue ◽  
Malignant Disease ◽  
Clinical Stage ◽  
Diagnostic Procedures ◽  
Basal Membrane ◽  
Needle Aspiration ◽  
Screening Mammography ◽  
Significant Difference ◽  
Malignant Lesions

Great importance in detecting cancer in the phase of in situ lays in the fact that the epithelial layer is deprived of blood and lymph vessels, so metastases may develop only when basal membrane has been broken. This paper includes 46 operated women in whom it preoperatively had been verified suspect non-palpable lesion. The preoperative diagnostics included use of high- resolution mammography, aimed mammography, palpatory examination, as well as fine-needle aspiration (FNA), biopsy and cytologic analysis of the sample. The methodology of this work implies the use of stereotaxic marking, specimen mammography and ex-tempore pathohistology analysis. Out of 46 investigated patients in clinical stage T0N0M0, in whom there were no signs of malignant disease, and according to suspect lesion of initial screening mammography, malignant lesions of breast tissue were diagnosed in 19 patients (41%) intraoperatively. Three of these lesions (15,8%) were histopathologically verified as in situ. Comparing our results with data of the Institute of oncology and radiology of Serbia hospital registry (IORS) for the year 2001, from 1173 patients registered with malignant lesions, only 16 ones (1,4%) had in situ cancer, operated on the basis of the suspect mammography of clinical stage T0N0M0. Statistically significant difference was found related to the number of detected cancers in this early phase of the breast malignant disease. This limits surgical intervention to tumorectomy, with preservation of the remaining breast tissue, what brings to healing, justifying in that way, screening examinations and routine application of the most contemporary diagnostic procedures.

scholarly journals Sampling strategies to evaluate the prognostic value of a new biomarker on a time-to-event end-point

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Francesca Graziano ◽  
Maria Grazia Valsecchi ◽  
Paola Rebora
Keyword(s):  
Survival Data ◽  
Prognostic Value ◽  
Cox Model ◽  
Lymphoblastic Leukemia ◽  
Fixed Ratio ◽  
Case Control ◽  
Time To Event ◽  
Full Cohort ◽  
Number Of Patients ◽  
Nested Case Control

Abstract Background The availability of large epidemiological or clinical data storing biological samples allow to study the prognostic value of novel biomarkers, but efficient designs are needed to select a subsample on which to measure them, for parsimony and economical reasons. Two-phase stratified sampling is a flexible approach to perform such sub-sampling, but literature on stratification variables to be used in the sampling and power evaluation is lacking especially for survival data. Methods We compared the performance of different sampling designs to assess the prognostic value of a new biomarker on a time-to-event endpoint, applying a Cox model weighted by the inverse of the empirical inclusion probability. Results Our simulation results suggest that case-control stratified (or post stratified) by a surrogate variable of the marker can yield higher performances than simple random, probability proportional to size, and case-control sampling. In the presence of high censoring rate, results showed an advantage of nested case-control and counter-matching designs in term of design effect, although the use of a fixed ratio between cases and controls might be disadvantageous. On real data on childhood acute lymphoblastic leukemia, we found that optimal sampling using pilot data is greatly efficient. Conclusions Our study suggests that, in our sample, case-control stratified by surrogate and nested case-control yield estimates and power comparable to estimates obtained in the full cohort while strongly decreasing the number of patients required. We recommend to plan the sample size and using sampling designs for exploration of novel biomarker in clinical cohort data.

scholarly journals Is It Definitely Clear That Long-Term Survival after Breast Cancer Surgery Is Not Affected by Anaesthetics?

Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3390
Author(s):  
Mats Enlund
Keyword(s):  
Breast Cancer ◽  
Survival Data ◽  
Retrospective Studies ◽  
Breast Cancer Surgery ◽  
Breast Cancer Patients ◽  
Term Survival ◽  
Long Term Survival ◽  
Significant Difference ◽  
One Year

Retrospective studies indicate that cancer survival may be affected by the anaesthetic technique. Propofol seems to be a better choice than volatile anaesthetics, such as sevoflurane. The first two retrospective studies suggested better long-term survival with propofol, but not for breast cancer. Subsequent retrospective studies from Asia indicated the same. When data from seven Swedish hospitals were analysed, including 6305 breast cancer patients, different analyses gave different results, from a non-significant difference in survival to a remarkably large difference in favour of propofol, an illustration of the innate weakness in the retrospective design. The largest randomised clinical trial, registered on clinicaltrial.gov, with survival as an outcome is the Cancer and Anesthesia study. Patients are here randomised to propofol or sevoflurane. The inclusion of patients with breast cancer was completed in autumn 2017. Delayed by the pandemic, one-year survival data for the cohort were presented in November 2020. Due to the extremely good short-term survival for breast cancer, one-year survival is of less interest for this disease. As the inclusions took almost five years, there was also a trend to observe. Unsurprisingly, no difference was found in one-year survival between the two groups, and the trend indicated no difference either.

scholarly journals L-Asparaginase, Doxorubicin, Vincristine, and Prednisolone (LHOP) Chemotherapy as a First-Line Treatment for Dogs with Multicentric Lymphoma

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2199
Author(s):  
Jih-Jong Lee ◽  
Albert Taiching Liao ◽  
Shang-Lin Wang
Keyword(s):  
Clinical Stage ◽  
Progression Free Survival ◽  
Cell Phenotype ◽  
Chop Chemotherapy ◽  
First Line ◽  
Canine Lymphoma ◽  
Free Survival ◽  
Significant Difference ◽  
Multicentric Lymphoma ◽  
First Line Treatment

Cyclophosphamide exhibits the weakest therapeutic effect compared with vincristine and doxorubicin in the CHOP (C, cyclophosphamide; H, doxorubicin; O, vincristine; and P, prednisolone) chemotherapeutic protocol for the treatment of canine lymphoma. Twenty dogs with multicentric lymphoma were treated using the LHOP protocol, which used l-asparaginase in place of cyclophosphamide, and the outcomes were historically compared with those of dogs that received CHOP chemotherapy in the same institution. No significant differences were found in age (p = 0.107), body weight (p = 0.051), sex (p = 0.453), clinical stage V (p = 1), substage b (p = 0.573), T-cell phenotype (p = 0.340), overall response (p = 1), and hypercalcaemia status (p = 1) between the LHOP and CHOP groups. The adverse effects of l-asparaginase were well tolerated and self-limiting. The median PFS (progression-free survival) and median ST (survival time) in the LHOP group were 344 days (range: 28–940 days) and 344 days (range: 70–940 days), respectively. The median PFS and median ST in the CHOP group were 234 days (range: 49–1822 days) and 314 days (range: 50–1822 days), respectively. The dogs that received LHOP chemotherapy had a significantly longer PFS than the dogs that received CHOP chemotherapy (p = 0.001). No significant difference was observed in ST between the LHOP and CHOP groups (p = 0.131). Our study findings thus indicate that the LHOP protocol can be used as a first-line chemotherapeutic protocol in canine multicentric lymphoma.

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