Sieve estimation of Cox models with latent structures

Biometrics ◽  
2016 ◽  
Vol 72 (4) ◽  
pp. 1086-1097
Author(s):  
Yongxiu Cao ◽  
Jian Huang ◽  
Yanyan Liu ◽  
Xingqiu Zhao
2020 ◽  
Vol 17 (1) ◽  
pp. 87-94
Author(s):  
Ibrahim A. Naguib ◽  
Fatma F. Abdallah ◽  
Aml A. Emam ◽  
Eglal A. Abdelaleem

: Quantitative determination of pyridostigmine bromide in the presence of its two related substances; impurity A and impurity B was considered as a case study to construct the comparison. Introduction: Novel manipulations of the well-known classical least squares multivariate calibration model were explained in detail as a comparative analytical study in this research work. In addition to the application of plain classical least squares model, two preprocessing steps were tried, where prior to modeling with classical least squares, first derivatization and orthogonal projection to latent structures were applied to produce two novel manipulations of the classical least square-based model. Moreover, spectral residual augmented classical least squares model is included in the present comparative study. Methods: 3 factor 4 level design was implemented constructing a training set of 16 mixtures with different concentrations of the studied components. To investigate the predictive ability of the studied models; a test set consisting of 9 mixtures was constructed. Results: The key performance indicator of this comparative study was the root mean square error of prediction for the independent test set mixtures, where it was found 1.367 when classical least squares applied with no preprocessing method, 1.352 when first derivative data was implemented, 0.2100 when orthogonal projection to latent structures preprocessing method was applied and 0.2747 when spectral residual augmented classical least squares was performed. Conclusion: Coupling of classical least squares model with orthogonal projection to latent structures preprocessing method produced significant improvement of the predictive ability of it.


2020 ◽  
Author(s):  
Annemarie Uhlig ◽  
Johannes Uhlig ◽  
Lutz Trojan ◽  
Michael Woike ◽  
Marianne Leitsmann ◽  
...  

The aim of this study was to evaluate the association between axitinib, sunitinib and temsirolimus toxicities and patient survival in metastatic renal cell cancer patients. Overall survival (OS) and progression-free survival (PFS) of metastatic renal cell cancer patients from the prospective multicenter STAR-TOR study were assessed using multivariable Cox models. A total of 1195 patients were included (n = 149 axitinib; n = 546 sunitinib; n = 500 temsirolimus). The following toxicities significantly predicted outcomes: hand–foot skin reaction (hazard ratio [HR] = 0.29) for PFS with axitinib; stomatitis (HR = 0.62) and pneumonitis (HR = 0.23) for PFS with temsirolimus; stomatitis (HR = 0.52) and thrombocytopenia (HR = 0.6) for OS with temsirolimus; fatigue (HR = 0.71) for PFS with sunitinib; hand–foot skin reaction (HR = 0.56) and fatigue (HR = 0.58) for OS with sunitinib. In conclusion, in metastatic renal cell cancer, axitinib, sunitinib and temsirolimus demonstrate specific toxicities that are protective OS/PFS predictors.


2019 ◽  
Vol 30 (1) ◽  
pp. 56-61
Author(s):  
Giorgio Bogani ◽  
Maria Grazia Tibiletti ◽  
Maria Teresa Ricci ◽  
Ileana Carnevali ◽  
Viola Liberale ◽  
...  

ObjectiveWomen with Lynch syndrome have a risk up to 40–60% of developing endometrial cancer, which is higher than their risk of developing colorectal or ovarian cancer. To date, no data on the outcomes of patients with Lynch syndrome diagnosed with non-endometrioid endometrial cancer are available. The goal of this study was to evaluate the outcome of patients with Lynch syndrome diagnosed with non-endometrioid endometrial cancer.MethodsData from consecutive patients diagnosed with Lynch syndrome and with a histological diagnosis of non-endometrioid endometrial cancer were retrospectively collected in two referral institutes in Italy. A case–control comparison (applying a propensity matching algorithm) was performed in order to compare patients with proven Lynch syndrome and controls. Inclusion criteria were: (a) histologically-proven endometrial cancer; (b) detection of a germline pathogenic variant in one of the MMR genes; (c) adequate follow-up. Only carriers of pathogenic or likely pathogenic variants (ie, class 5 and 4 according to the InSiGHT classification) were included in the study. Survival outcomes were assessed using KaplanMeier and Cox models.ResultsOverall, 137 patients with Lynch syndrome were collected. Mean patient age was 49.2 (10.9) years. Genes involved in the Lynch syndrome included MLH1, MSH2, and MSH6 in 43%, 39%, and 18% of cases, respectively. The study population included 27 patients with non-endometrioid endometrial cancer, who were matched 1:2 with patients with sporadic cancers using a propensity matching algorithm. After a median follow-up of 134 months (range 1–295), 2 (7.4%) of the 27 patients developed recurrent disease (3 and 36 months) and subsequently died of disease (7 and 91 months). Patients diagnosed with Lynch syndrome experienced better disease-free survival (HR 7.86 (95% CI 1.79 to 34.5); p=0.006) and overall survival (HR 5.33 (95% CI 1.18 to 23.9); p=0.029) than controls.ConclusionsNon-endometrioid endometrial cancer occurring in patients with Lynch syndrome might be associated with improved oncologic outcomes compared with controls. Genetic/molecular profiling should be investigated in order to better understand the mechanism underlying the prognosis.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
E Calero ◽  
E Hidalgo ◽  
R Marin ◽  
L Rosenfeld ◽  
I Fernandez ◽  
...  

Abstract Background Self-care is a crucial factor in the education of patients with heart failure (HF) and directly impacts in the progression of the disease. However, little is published about its major clinical implications as admission or mortality in patients with HF. Aims and methods The aim of the study was to analyze time to admission due to acute heart failure and mortality associated with poor self-care in patients with chronic HF. We prospectively recruited consecutive patients with stable chronic HF referred to a nurse-led HF programme. Selfcare was evaluated at baseline with the 9 item European Heart Failure Self-Care Behavior Scale. Scores were standardized and reversed from 0 (worst selfcare) to 100 (better self care). For the purpose of this study we analyzed the associations of worse self-care (defined as scores below the lower tertile of the scale) with demographic, disease-related (clinical) and psychosocial factors in all patients at baseline. Results We included 1123 patients, mean age 72±11, 639 (60%) were male, mean LVEF 45±17 and 454 (40,4%) were in NYHA class III or IV. Mean score of the 9-item ESCBE was 69±28. Score below 55 (lower tertile) defined impaired selfcare behaviour. Those patients with worse self-care had more ischaemic heart disease, more COPD, and they achieved less distance in the 6 minute walking test. Regarding psychosocial items patients in lower tertile of self-care needed a caregiver more frequently, they present more cognitive impairment, depressive symptoms and worse score in terms of health self-perception. Multivariate Cox Models showed that a score below 55 points in 9-item ESCBE was independently associated with higher readmission due to acute heart failure [HR 1.26 (1.02–1.57), p value=0.034] and with mortality [HR 1.24 CI95% (1.02–1.50), p value=0.028] Conclusion Poor self-care measured with the modified 9-item ESCBE was associated with higher risk of admission due to acute decompensation and higher risk of mortality in patients with chronic heart failure. These results highlight the importance of assessing self-care and provide measures to improve them. Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): Hospital Univesitario de Bellvitge


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 264-264
Author(s):  
Manuel Montero Odasso ◽  
Mark Speechley ◽  
Richard Camicioli ◽  
Nellie Kamkar ◽  
Qu Tian ◽  
...  

Abstract BACKGROUND: The concurrent decline in gait speed and cognition are associated with future dementia. However, the clinical profile of those who present with dual-decline has not yet been described. We aimed to describe the phenotype and risk for incident dementia of individuals who present a dual-decline in comparison with non dual-decliners. METHODS: Prospective cohort of community-dwelling older adults free of dementia at baseline. We evaluated participants’ gait speed, cognition, medical status, functionality, incidence of adverse events, and dementia biannually over 7 years. Gait speed was assessed with a 6-meter electronic-walkway, and global cognition was assessed using the MoCA test. We compared characteristics between dual-decliners and non dual-decliners using t-test, Chi-square, and hierarchical regression models. We estimated incident dementia using Cox models. RESULTS: Among 144 participants (mean age 74.23 ± 6.72 years, 54% women), 17% progressed to dementia. Dual-decliners had a three-fold risk (HR: 3.12, 95%CI:1.23-7.93, p=0.017) of progression to dementia compared with non dual-decliners. Dual-decliners were significantly older with a higher prevalence of hypertension and dyslipidemia (p=0.002). Hierarchical regression models show that age and sex alone explained 3% of the variation in the dual-decliners group, while adding hypertension and dyslipidemia increased the explained variation to 8% and 10 %, respectively. The risk of becoming a dual-decliner was 4-fold if hypertension was present. CONCLUSION: Older adults with concurrent decline in gait speed and cognition represent a group at the highest risk of progression to dementia. These dual-decliners have a distinct phenotype with a higher prevalence of hypertension, a potentially treatable condition.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Feng Jiang ◽  
Chuyan Wu ◽  
Ming Wang ◽  
Ke Wei ◽  
Jimei Wang

AbstractOne of the most frequently identified tumors and a contributing cause of death in women is breast cancer (BC). Many biomarkers associated with survival and prognosis were identified in previous studies through database mining. Nevertheless, the predictive capabilities of single-gene biomarkers are not accurate enough. Genetic signatures can be an enhanced prediction method. This research analyzed data from The Cancer Genome Atlas (TCGA) for the detection of a new genetic signature to predict BC prognosis. Profiling of mRNA expression was carried out in samples of patients with TCGA BC (n = 1222). Gene set enrichment research has been undertaken to classify gene sets that vary greatly between BC tissues and normal tissues. Cox models for additive hazards regression were used to classify genes that were strongly linked to overall survival. A subsequent Cox regression multivariate analysis was used to construct a predictive risk parameter model. Kaplan–Meier survival predictions and log-rank validation have been used to verify the value of risk prediction parameters. Seven genes (PGK1, CACNA1H, IL13RA1, SDC1, AK3, NUP43, SDC3) correlated with glycolysis were shown to be strongly linked to overall survival. Depending on the 7-gene-signature, 1222 BC patients were classified into subgroups of high/low-risk. Certain variables have not impaired the prognostic potential of the seven-gene signature. A seven-gene signature correlated with cellular glycolysis was developed to predict the survival of BC patients. The results include insight into cellular glycolysis mechanisms and the detection of patients with poor BC prognosis.


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