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1.
Journal of Southern Medical University ; (12): 952-963, 2023.
Artículo en Chino | WPRIM | ID: wpr-987008

RESUMEN

OBJECTIVE@#To compare the performance of machine learning models and traditional Cox regression model in predicting postoperative outcomes of patients with esophagogastric junction adenocarcinoma (AEG).@*METHODS@#This study was conducted among 203 AEG patients with complete clinical and follow-up data, who were treated in our hospital between September, 2015 and October, 2020. The clinicopathological data of the patients were processed for analysis using R language package and divided into training and validation datasets at the ratio of 3:1. The Cox proportional hazards regression model and 4 machine learning models were constructed for analyzing the datasets. ROC curves, calibration curves and clinical decision curves (DCA) were plotted. Internal validation of the machine learning models was performed to assess their predictive efficacy. The predictive performance of each model was evaluated by calculating the area under the curve (AUC), and the model fitting was assessed using the calibration curve.@*RESULTS@#For predicting 3-year survival based on the validation dataset, the AUC was 0.870 for Cox proportional hazard regression model, 0.901 for eXtreme Gradient Boosting (XGBoost), 0.791 for random forest, 0.832 for support vector machine, and 0.725 for multilayer perceptron; For predicting 5-year survival, the AUCs of these models were 0.915, 0.916, 0.758, 0.905, and 0.737, respectively. For internal validation, the AUCs of the 4 machine learning models decreased in the order of XGBoost (0.818), random forest (0.758), support vector machine (0.0.804), and multilayer perceptron (0.745).@*CONCLUSION@#The machine learning models show better predictive efficacy for survival outcomes of patients with AEG than Cox proportional hazard regression model, especially when proportional odds assumption or linear regression models are not applicable. XGBoost models have better performance than the other machine learning models, and the multi-layer perception model may have poor fitting results for a limited data volume.


Asunto(s)
Humanos , Adenocarcinoma , Pronóstico , Aprendizaje Automático , Unión Esofagogástrica
2.
Belo Horizonte; s.n; 2023. 131 p. ilus, tab.
Tesis en Portugués | LILACS, BDENF | ID: biblio-1427028

RESUMEN

Introdução: As doenças cardiovasculares são o principal problema de saúde pública em todo o mundo. Portanto, a avaliação do risco cardiovascular, com a identificação de seus fatores de risco e de proteção e de suas trajetórias ao longo do tempo são importantes para a proposição, a consolidação e a implementação de medidas de prevenção da ocorrência de doenças cardiovasculares. Objetivo geral: Analisar a trajetória e os determinantes do alto risco cardiovascular de 30 anos em participantes da Coorte de Universidades Mineiras (Estudo CUME). Métodos: Inicialmente, foi realizada uma revisão integrativa da literatura e, em seguida, dois estudos de coorte prospectiva. A) Artigo 1 ­ revisão integrativa da literatura sobre a estimação do alto risco cardiovascular e seus fatores associados, realizada nas bases Medical Literature Analysis and Retrievel System Online, Web of Science, Excerpta Medica Database, Cumulative Index to Nursing and Allied Health Literature e no portal Biblioteca Virtual de Saúde; B) Artigo 2 ­ Coorte aberta prospectiva desenvolvida com 2.854 participantes do Estudo CUME, que é uma pesquisa multicêntrica conduzida com egressos de sete instituições públicas federais de ensino superior do Estado de Minas Gerais desde 2016. A incidência do alto risco cardiovascular de 30 anos foi calculada usando o escore de Framingham e seus determinantes foram estimados usando análise multivariada hierárquica pela técnica de regressão de Cox; C) Artigo 3 ­ Estudo prospectivo fechado desenvolvido com 1.286 participantes da CUME, que responderam ao questionário da linha de base em 2016, aos questionários de seguimento de dois anos (2018) e de quatro anos (2020). O risco cardiovascular foi avaliado com o escore de Framingham de 30 anos. A identificação das trajetórias do risco cardiovascular foi realizada com a técnica de modelagem de crescimento de classe latente com o uso do modelo normal censurado. A análise dos fatores independentemente associados a cada uma das trajetórias foi conduzida com a técnica de regressão logística multinominal. Resultados: Artigo 1 ­ foram selecionados 13 artigos com um ou mais fatores associados ao alto risco cardiovascular, segundo o escore de Framingham de 10 anos. Nenhum artigo investigou os fatores associados ao alto risco cardiovascular de 30 anos. Artigo 2 ­ após média de 2,62 anos de seguimento, a incidência do alto risco cardiovascular de 30 anos foi 8,1 casos/1.000 pessoas-ano no sexo feminino e 20,2 casos/1.000 pessoas-ano no sexo masculino. Sexo masculino (Hazard Ratio ­ HR: 2,34; IC 95%: 1,58 - 3,46), trabalhar (HR: 2,13; IC 95%: 1,13 - 3,99), alto consumo de alimentos processados (HR: 2,44; 95% CI: 1,21 - 4,90) e ser ativo fisicamente (HR: 0,63; IC 95%: 0,41 - 0,98) se associaram independentemente ao alto risco cardiovascular de 30 anos; Artigo 3 - Três trajetórias de risco cardiovascular de 30 anos foram identificadas: Baixo-Baixo (68,3%), Médio-Médio (26,2%) e Alto-Alto (5,5%). Ao longo do tempo, o risco cardiovascular apresentou discreto aumento para a trajetória Baixo-Baixo (2,9%), moderado aumento para a trajetória Médio-Médio (7,6%) e elevado aumento para a trajetória Alto-Alto (13%). O sexo masculino, viver em união estável, ter consumos moderado e alto de alimentos ultraprocessados se associaram positivamente às trajetórias de risco cardiovascular Médio-Médio e Alto-Alto. Ainda, ter formação profissional fora da área da saúde e estar trabalhando se associaram positivamente à trajetória de risco cardiovascular Médio-Médio, enquanto ser ativo fisicamente se associou negativamente à trajetória de risco cardiovascular Alto-Alto. Conclusão: Poucos estudos foram conduzidos para avaliar o alto risco cardiovascular de 30 anos, sendo que em nenhum deles foram estimados fatores associados ao desfecho. Nossos achados científicos indicaram que praticar atividade física reduz a incidência do alto risco cardiovascular de 30 anos. Homens, pessoas que trabalham e com consumo elevado de alimentos processados devem ser monitorados com maior cautela, pois apresentaram maior susceptibilidade de ocorrência do alto risco cardiovascular de 30 anos. Adultos jovens e com melhor situação socioeconômica possuem uma trajetória de baixo risco cardiovascular de 30 anos, entretanto, há uma tendência de piora desta trajetória ao longo do tempo devido aos maus hábitos de vida. Dessa forma, é essencial a implementação de estratégias de prevenção para evitar o adoecimento cardiovascular.


Introduction: Cardiovascular diseases are the main public health problem worldwide. Therefore, the assessment of cardiovascular risk, with the identification of its risk and protection factors and their trajectories over time, are important for proposing, consolidating and implementing measures to prevent the occurrence of cardiovascular diseases. General objective: To analyze the 30-year trajectory and determinants of high cardiovascular risk in participants of the Cohort of Universities of Minas Gerais (CUME Study). Methods: Initially, an integrative literature review was performed, followed by two prospective cohort studies. A) Article 1 ­ integrative review of the literature on the estimation of high cardiovascular risk and its associated factors, carried out in the databases Medical Literature Analysis and Retrievel System Online, Web of Science, Excerpta Medica Database, Cumulative Index to Nursing and Allied Health Literature and the Virtual Health Library portal; B) Article 2 ­ Prospective open cohort developed with 2,854 participants of the CUME Study, which is a multicenter research conducted with graduates from seven federal public institutions of higher education in the State of Minas Gerais since 2016. The incidence of high cardiovascular risk at 30 years was calculated using the Framingham score and its determinants were estimated using hierarchical multivariate analysis by the Cox regression technique; C) Article 3 ­ Prospective closed study developed with 1,286 participants from CUME, who answered the baseline questionnaire in 2016, the two-year follow-up questionnaire in 2018 and the four-year follow-up questionnaire in 2020. The risk Cardiovascular was assessed using the 30-year Framingham score. The identification of cardiovascular risk trajectories was performed using the latent class growth modeling technique using the normal censored model. The analysis of the factors independently associated with each of the trajectories was conducted using the multinomial logistic regression technique. Results: Article 1 ­ 13 articles were selected with one or more factors associated with high cardiovascular risk, according to the Framingham score over 10 years. No article investigated the factors associated with 30-year high cardiovascular risk. Article 2 ­ After an average of 2.62 years of follow-up, the incidence of high cardiovascular risk at 30 years was 8.1 cases/1,000 person-years in females and 20.2 cases/1,000 person-years in males. Male sex (Hazard Ratio ­ HR: 2.34; 95% CI: 1.58 - 3.46), work (HR: 2.13; 95% CI: 1.13 - 3.99), high food intake processed foods (HR: 2.44; 95% CI: 1.21 - 4.90) and being physically active (HR: 0.63; 95% CI: 0.41 - 0.98) were independently associated with high cardiovascular risk 30 years old; Article 3 - Three 30-year cardiovascular risk trajectories were identified: Low-Low (68.3%), Medium-Medium (26.2%) and High-High (5.5%). Over time, cardiovascular risk showed a slight increase for the Low-Low trajectory (2.9%), a moderate increase for the Medium-Medium trajectory (7.6%) and a high increase for the High-High trajectory (13%). Being male, living in a stable relationship, having moderate and high consumption of ultra-processed foods were positively associated with Medium-Medium and High-High cardiovascular risk trajectories. Also, having professional training outside the health area and being working were positively associated with the Medium-Medium cardiovascular risk trajectory, while being physically active was negatively associated with the High-High cardiovascular risk trajectory. Conclusion: Few studies were conducted to assess the 30-year high cardiovascular risk, and none of them estimated factors associated with the outcome. Our scientific findings indicated that practicing physical activity reduces the incidence of 30-year high cardiovascular risk. Men, people who work and with a high consumption of processed foods should be monitored with greater caution, as they were more susceptible to the occurrence of the high cardiovascular risk of 30 years. Young adults with better socioeconomic status have a 30-year trajectory of low cardiovascular risk, however, there is a tendency for this trajectory to worsen over time due to bad lifestyle habits. Thus, it is essential to implement prevention strategies to avoid cardiovascular disease.


Asunto(s)
Modelos de Riesgos Proporcionales , Estudios Longitudinales , Factores de Riesgo de Enfermedad Cardiaca , Estudios de Cohortes , Tesis Académica , Perspectiva del Curso de la Vida
3.
Journal of Sun Yat-sen University(Medical Sciences) ; (6): 224-231, 2023.
Artículo en Chino | WPRIM | ID: wpr-965837

RESUMEN

ObjectiveTo understand the composition of related characteristics of HIV/AIDS cases in Lanzhou and analyze the influencing factors of AIDS-related deaths. MethodsThe information of HIV/AIDS cases reported in Lanzhou from 2011 to 2019 was collected, the method of survival was used analysis and Bayesian Cox Proportional Hazard Regression Model was constructed to analyze the related factors of death. ResultsA total of 2 312 HIV/AIDS patients were selected in this study, including 45 AIDS-related deaths. The results of multivariate regression showed that the older the patients were, the higher the risk of death was; the risk of death of AIDS patients at the time of diagnosis was 13.91 times higher than that of HIV-infected patients; Patients who received CD4 testing had a lower risk of death than those who did not; The risk of death was 0.22 times higher among those who received antiretroviral therapy than those who did not receive antiretroviral therapy. ConclusionsAge at diagnosis, course of disease, antiviral therapy were the influencing factors of AIDS-related death in HIV/AIDS patients in Lanzhou. Therefore, it is necessary to strengthen health education for AIDS-related groups, advocate early detection, early diagnosis, and early treatment, expand the coverage of AIDS testing and treatment, prolong the survival time of AIDS patients.

4.
Ethiopian Journal of Health Sciences ; 32(5): 937-946, 5 September 2022. Tables
Artículo en Inglés | AIM | ID: biblio-1398385

RESUMEN

Diabetic retinopathy is a complication of diabetes, caused by high blood sugar levels damaging the eye. Globally, diabetic retinopathy affects more than 103.12 million people. Diabetic retinopathy is among the leading causes of vision loss at the global level, including in Ethiopia. Therefore, the study aimed to assess the time to develop diabetic retinopathy and identify factors associated with diabetic retinopathy among diabetes patients. METHODS: A retrospective study was conducted from September 1, 2021, to January 30, 2022. Data was collected using semi structured questionnaire. The Cox proportional hazard model were used to determine the median time to develop diabetic retinopathy and identify predictors of diabetic retinopathy. Data was analyzed using R software. RESULTS: A total of 373 diabetes patients were included in this study. The prevalence of diabetic retinopathy was 41.3%. The median time was 41 months, ranging from 39 to 73 months. Elder age (HR=3.17, 95%CI: 1.53, 6.58), being male (HR=2.34, 95%CI: 1.35,6.15), previous family history of diabetes (HR=4.16, 95%CI: 2.19, 8.37), longer duration of diabetes (HR=2.86, 95%CI: 1.41, 5.31) received only insulin therapy (HR=3.91, 95%CI: 1.36, 7.94), and high systolic blood pressure (HR=2.32; 95%CI: 1.12, 4.39) were statistically significant factors related to development of diabetes retinopathy. CONCLUSIONS: More than half of diabetic patinets in this study were developed retinopathy diabetes within a few months of being diagnosed. As a result, we advocate that the best way to preserve our vision from diabetic retinopathy is to maintain our diabetes under control, and the high-risk population receive early screening for diabetes


Asunto(s)
Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Retinopatía Diabética , Neuropatía Mediana , Complicaciones de la Diabetes , Hipertensión
5.
Journal of Preventive Medicine ; (12): 762-767, 2021.
Artículo en Chino | WPRIM | ID: wpr-886491

RESUMEN

Objective@#To compare the effects of Cox proportional hazard regression model (Cox model) and extreme gradient boosting model ( XGBoost model ) on the prediction of the mortality of acute paraquat poisoning (APP).@*Methods@#The APP cases admitted to Qingdao Eighth People's Hospital and Shandong Provincial Hospital from January 1st of 2018 to December 1st of 2020 was recruited and divided into a training group and a verification group by a random number table. The Cox model and XGBoost model were established to select the predictors for APP mortality. Receiver operating characteristic ( ROC ) curve was drawn to analyze the predictive power of the two models, and the calibration was evaluated using Hosmer-Lemeshow test.@*Results@#Totally 150 APP cases were recruited. There were 75 cases each in the training group and in the verification group, with 52 and 55 cases died respectively, accounting for 69.33% and 73.33%. The Cox model showed that paraquat intake, the time from taking poison to seeing a doctor, the time for the first perfusion, the time for the first vomiting, aspartate aminotransferase, alanine aminotransferase, serum creatinine, blood urea nitrogen, white blood cell, lactic acid, creatine kinase isoenzymes, glucose, serum calcium and serum potassium were the predictors of APP mortality ( all P<0.05 ). The XGboost model showed that the predictive power of the factors in a descending order were the time from taking poison to seeing a doctor, the time for the first vomiting, the time for the first perfusion, lactic acid, white blood cell, paraquat intake, serum creatinine, serum potassium, serum calcium, creatine kinase isoenzymes, glucose, aspartate aminotransferase, blood urea nitrogen and alanine aminotransferase. The area under curve ( AUC ) of the XGBoost model for predicting was 0.972, which was greater than 0.921 of the Cox model ( P<0.05 ). The predicted results of the Cox model and XGBoost model were consistent with the actual situation ( P>0.05 ). @*Conclusion@#The Cox model and XGBoost model are consistent in predicting the mortality of APP, but the latter is better.

6.
Chinese Journal of Cancer Biotherapy ; (6): 55-59, 2021.
Artículo en Chino | WPRIM | ID: wpr-872636

RESUMEN

@#[Abstract] Objective: To investigate the expression of zinc-α2-glycoprotein 1 (AZGP1) in osteosarcoma tissue and its relationship with clinicopathological features and prognosis of patients. Methods: A total of 62 pairs of cancer tissue and adjacent normal tissue samples from patients with osteosarcoma treated in the Department of Orthopedics, Second People's Hospital of Nanyang City were collected from August 2012 to August 2014. The expressions of AZGP1 in osteosarcoma tissues and adjacent tissues were detected by using immunohistochemical staining. All patients were followed up on the second day after the operation. The deadline was August 31, 2019. All patients were followed up for 5 years, with death as the end event. The number of end events within 5 years and overall survival (OS) time of the patients were recorded. Kaplan-Meier method was used for survival analysis, and Cox proportional hazard model was used for multivariate analysis of factors affecting patients’ survival. Results: The positive expression rate of AZGP1 in the osteosarcoma tissues was significantly higher than that in the adjacent tissues (77.42% vs 32.26%, P<0.01). There were significant differences in the positive expression rates of AZGP1 in patients with different Eneeking stages, soft tissue infiltration or not and lung metastasis conditions (all P<0.05). Kaplan-Meier survival analysis showed that the average OS time and 5-year OS rate of patients in the AZGP1 positive expression group were significantly lower than those in the negative expression group [(24.19±2.68) months vs (43.07±3.70) months, P<0.01; 18.75% vs 64.29%, P<0.01]. The lung metastasis and positive expression of AZGP1 were risk factors affecting the prognosis of patients with osteosarcoma (HR=3.407, 3.647, all P<0.05). Conclusion: AZGP1 is highly expressed in osteosarcoma tissues, and it is related to the malignant indicators and prognosis of patients. It may be a potential marker for evaluating the prognosis of osteosarcoma patients.

7.
Chinese Journal of Cancer Biotherapy ; (6): 1378-1382, 2020.
Artículo en Chino | WPRIM | ID: wpr-862246

RESUMEN

@#[Abstract] Objective: To investigate the expression and clinical significance of long non-coding RNA (lncRNA) HOTTIP in tissues of patients with endometrial carcinoma. Methods: A total of 109 cases of patients with endometrial carcinoma who underwent surgery in Xingxiang Central Hospital from April 2012 to April 2014 were selected. The endometrial carcinoma tissue and its corresponding adjacent tissue (more than 5 cm from the cancer margin) were obtained. The expressions of HOTTIP in endometrial carcinoma and adjacent tissues were detected by qRT-PCR. All patients were followed up from the first postoperative day. The follow-up deadline was April 30, 2019. The end-point event was death and the patient's survival time was recorded. Results: The relative expression level of HOTTIP in endometrial carcinoma tissues was (2.55±0.21), which was higher than that in the adjacent tissue (1.03±0.16) (t=60.631, P<0.01). The differences of the relative expression levels of HOTTIP in endometrial carcinoma tissues between different FIGO stage, histological grade, depth of myometrial invasion, lymphatic vascular infiltration status and lymph node metastasis were statistically significant (all P<0.05). Kaplan-Meier survival analysis showed that the 5-year survival rate and the survival time in the low expression group were higher than those in the high expression group [78.57% vs 37.04%, (70.67±4.94) months vs (42.14±3.65) months], the difference was statistically significant (χ2=12.839, P<0.01). Cox proportional hazards regression model analysis showed that the FIGO stage [HR=2.248 (95%CI: 1.034-4.887)], myometrial invasion depth [HR=3.055 (95%CI: 1.668-5.592)], lymph node metastasis [HR=3.811 (95%CI: 1.786-8.131)] and the expression of HOTTIP [HR=2.649 (95%CI: 1.026-6.842)] were all independent influence factors for the prognosis of patients with endometrial carcinoma. Conclusion: lncRNA HOTTIP is highly expressed in endometrial carcinoma tissues and associated with malignant progression of patients. It is an independent influencing factor for patients’ prognosis.

8.
Korean Journal of Anesthesiology ; : 441-457, 2019.
Artículo en Inglés | WPRIM | ID: wpr-759568

RESUMEN

As a follow-up to a previous article, this review provides several in-depth concepts regarding a survival analysis. Also, several codes for specific survival analysis are listed to enhance the understanding of such an analysis and to provide an applicable survival analysis method. A proportional hazard assumption is an important concept in survival analysis. Validation of this assumption is crucial for survival analysis. For this purpose, a graphical analysis method and a goodness-of-fit test are introduced along with detailed codes and examples. In the case of a violated proportional hazard assumption, the extended models of a Cox regression are required. Simplified concepts of a stratified Cox proportional hazard model and time-dependent Cox regression are also described. The source code for an actual analysis using an available statistical package with a detailed interpretation of the results can enable the realization of survival analysis with personal data. To enhance the statistical power of survival analysis, an evaluation of the basic assumptions and the interaction between variables and time is important. In doing so, survival analysis can provide reliable scientific results with a high level of confidence.


Asunto(s)
Humanos , Estudios de Seguimiento , Métodos , Modelos de Riesgos Proporcionales , Estadística como Asunto , Análisis de Supervivencia
9.
Korean Journal of Family Practice ; (6): 366-372, 2019.
Artículo en Coreano | WPRIM | ID: wpr-787479

RESUMEN

BACKGROUND: To investigate the impact of national health screening on all-cause mortality risk, aged over 45.METHODS: Data from Korean Longitudinal Study of Aging 2006–2014 were assessed. A total of 10,254 participants were included at baseline, and survival rate was assessed biennially. Using cox proportional hazards model, the effect of health screening on mortality risk was investigated. Covariates were gender, depression, education, marital status, co-habitants, house income, social engagement, economic satisfaction, private health insurance, residence location, chronic diseases, and health behaviors (smoking, alcohol intake, regular exercise).RESULTS: At baseline 2006, 54.4% of participants didn't undergo health screening. A hazard ratio (HR) for mortality risk of non-participants were 1.36 (95% confidence interval [CI], 1.21–1.53) after adjusting age and gender. Adding marital status and co-habitants to model 1 as covariates, HR was 1.34 (95% CI, 1.18–1.50) (model 2). Adding depression scores and socioeconomic vulnerabilities to model 2, HR was 1.29 s (95% CI, 1.14–1.45) (model 3). Adding chronic diseases to model 3, HR was 1.26 (95% CI, 1.14–1.48) (model 4). Finally, health behaviors have been added to model 4, HR was 1.24 (95% CI, 1.10–1.40) (model 5). In addition, the mortality risk increased as the cumulative number of missing health screenig increased accordingly.CONCLUSION: Health screening was an independent factor to reduce mortality risk. Therefore, active encouragement to participate the health screening should be implemented to reduce all-cause mortality.


Asunto(s)
Envejecimiento , Enfermedad Crónica , Depresión , Educación , Conductas Relacionadas con la Salud , Seguro de Salud , Corea (Geográfico) , Estudios Longitudinales , Estado Civil , Tamizaje Masivo , Mortalidad , Modelos de Riesgos Proporcionales , Tasa de Supervivencia
10.
China Oncology ; (12): 134-139, 2018.
Artículo en Chino | WPRIM | ID: wpr-701064

RESUMEN

Background and purpose: Osteosarcoma is a tumor originated from mesenchymal tissue, which often occurs in teenagers. It often occurs in long bones, rarely in maxillofacial regions. The present treatment is mainly in surgery followed by chemotherapy and radiation. It is an infrequent disease and hardly reported. In this study, we compared clinical differences in 32 maxillofacial osteosarcoma patients and identified the prognostic factors in the disease. Methods: The clinical data of 32 osteosarcoma patients were retrospectively reviewed. The data covered the period from Jan. 2010 to Jan. 2017, and included sex, age, tumor site. The mean follow-up time was 75 months (ranging from 7 to 90 months). The Kaplan-Meier method was used to measure the overall survival rate. A log-rank univariate analysis was used to determine the prognostic factors related to the survival rate. The Cox model multivariate analysis was used to identify independent prognostic factors. Results: The median survival time of 32 patients in the present study was (47.6±8.4) months (95%CI: 31.1-64.1). The 1-and 2-year cumulative survival rates were 84% and 72%, respectively. The 5-year cumulative survival rate was 44%. Log-rank univariate analysis showed that the significant factors were size, surgical margin and frequency of adjuvant chemotherapy. Surgical margin and frequency of adjuvant chemotherapy were closely related to recurrence. Cox regression analysis revealed that surgical margin and frequency of adjuvant chemotherapy were the prognostic factors. Conclusions: Maxillofacial osteosarcoma has unique features and prognosis. Surgical margin and frequency of adjuvant chemotherapy were the prognostic factors in osteosarcoma.

11.
Ciênc. Saúde Colet. (Impr.) ; 22(11): 3743-3754, Nov. 2017. tab, graf
Artículo en Portugués | LILACS | ID: biblio-890211

RESUMEN

Resumo O objetivo deste estudo foi estimar os efeitos de fatores prognósticos na sobrevida do câncer de mama, como idade, estadiamento e extensão do tumor, utilizando modelos de riscos proporcionais de Cox e de riscos competitivos de Fine-Gray. É um estudo de coorte retrospectiva de base-populacional referente a 524 mulheres diagnosticadas com câncer de mama no período de 1993 a 1995, acompanhadas até 2011, residentes no município de Campinas, São Paulo, Brasil. O ponto de corte (cutoff) da variável idade foi definido utilizando-se modelos simples de Cox. Nos ajustes de modelos simples e múltiplo de Fine-Gray, a idade não foi significativa na presença de riscos competitivos e nem nos modelos de Cox, considerando-se, para ambas as modelagens, óbito por câncer de mama como desfecho de interesse. As curvas de sobrevidas estimadas por Kaplan-Meier evidenciaram diferenças expressivas para óbitos por câncer de mama e por riscos competitivos. As curvas de sobrevida por câncer de mama não apresentaram diferenças significativas quando comparados os grupos de idades, segundo teste de log rank. Os modelos de Cox e de Fine-Gray identificaram os mesmos fatores prognósticos que influenciavam na sobrevida do câncer de mama.


Abstract This study aimed to estimate the effects of prognostic factors on breast cancer survival, such as age, staging, and extension of the tumor, using proportional hazards and competing risks models proposed by Cox and Fine-Gray, respectively. This is a retrospective cohort study, based on a population of 524 women, who were diagnosed with breast cancer in the period from 1993 to 1995 and monitored until 2011, residents in the city of Campinas, São Paulo, Brazil. The cutoff points for the variable of age were defined with Cox simple models. In the settings of simple and multiple Fine-Gray models, age was not significant to the presence of competing risks, neither it was in Cox models. For both models, death by breast cancer was the event of interest. The survival functions, estimated by Kaplan-Meier, showed significant differences for deaths by breast cancer and by competing risks. Survival functions by breast cancer did not show significant differences when comparing the age groups, according to log-rank test. Cox and Fine-Gray models identified the same prognostic factors that influenced in breast cancer survival.


Asunto(s)
Humanos , Femenino , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Modelos Estadísticos , Pronóstico , Brasil/epidemiología , Neoplasias de la Mama/epidemiología , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Estudios Retrospectivos , Factores de Riesgo , Estudios de Cohortes , Factores de Edad , Persona de Mediana Edad , Estadificación de Neoplasias
12.
Rev. adm. pública (Online) ; 51(5): 708-733, set.-out. 2017. tab, graf
Artículo en Portugués | LILACS | ID: biblio-897242

RESUMEN

Resumo Neste artigo utilizamos microdados do Cadastro Único combinados com dados da Relação Anual de Informações Sociais (Rais) para examinar a duração do emprego entre indivíduos de famílias beneficiárias do Programa Bolsa Família. Para tanto, estimamos modelos de riscos proporcionais de Cox para comparar a duração no emprego entre beneficiários e não beneficiários do programa utilizando uma base de dados com mais de três milhões de indivíduos pertencentes a famílias de baixa renda. Os resultados sugerem que o risco de desligamento do emprego para os beneficiários do Programa Bolsa Família é entre 7% e 10% menor do que para os não beneficiários. Modelos paramétricos também foram ajustados para verificação de robustez, produzindo resultados equivalentes aos do modelo de Cox. Em todos os casos, a participação no programa foi observada por meio de uma covariável variando no tempo, extraída diretamente das folhas de pagamento do programa.


Resumen En este artículo utilizamos microdatos del registro nacional de personas pobres (Cadastro Único) combinados con datos de la Relación Anual de Informaciones Sociales (Rais) para examinar la duración del empleo entre individuos de familias beneficiadas por el Programa Bolsa Família. Por lo tanto, se estima un modelo de riesgos proporcionales de Cox para comparar la duración del empleo entre beneficiarios y no beneficiarios del programa, utilizando una base de datos con más de tres millones de individuos pertenecientes a familias de bajos recursos. Los resultados sugieren que el riesgo de extinción de empleo para los beneficiarios del Programa Bolsa Família es entre un 7% y un 10% inferior a la de los no usuarios. Modelos paramétricos también fueron ajustados para verificación de robustez, produciendo resultados equivalentes a los del modelo de Cox. En todos los casos, la participación en el programa fue observada a través de una covariable variando en el tiempo, extraída directamente de la nómina del programa.


Abstract This article uses microdata from the Unified Registry of Social Programs (CadUnico) and the Annual Social Information Report (Rais) to examine the duration of employment for families receiving benefits from the Bolsa Família Program. To achieve this goal, Cox proportional hazard models were used to estimate the job duration for beneficiaries and non-beneficiaries of the program using a database of more than three million people. The findings indicate that the risk of leaving work among beneficiaries of the Bolsa Família Program is 7% to 10% lower than the risk for non-beneficiaries. Parametric models were also adjusted to verify robustness, producing results equivalent to those of the Cox model. In all cases, participation in the program was observed through a covariate that varies over time, extracted directly from the program's payment records.


Asunto(s)
Pobreza , Familia , Riesgo , Empleo , Programas Sociales , Renta
13.
Chinese Journal of Epidemiology ; (12): 737-740, 2016.
Artículo en Chino | WPRIM | ID: wpr-736023

RESUMEN

Conditional logistic regression analysis and unconditional logistic regression analysis are commonly used in case control study,but Cox proportional hazard model is often used in survival data analysis.Most literature only refer to main effect model,however,generalized linear model differs from general linear model,and the interaction was composed of multiplicative interaction and additive interaction.The former is only statistical significant,but the latter has biological significance.In this paper,macros was written by using SAS 9.4 and the contrast ratio,attributable proportion due to interaction and synergy index were calculated while calculating the items of logistic and Cox regression interactions,and the confidence intervals of Wald,delta and profile likelihood were used to evaluate additive interaction for the reference in big data analysis in clinical epidemiology and in analysis of genetic multiplicative and additive interactions.

14.
Chinese Journal of Epidemiology ; (12): 737-740, 2016.
Artículo en Chino | WPRIM | ID: wpr-737491

RESUMEN

Conditional logistic regression analysis and unconditional logistic regression analysis are commonly used in case control study,but Cox proportional hazard model is often used in survival data analysis.Most literature only refer to main effect model,however,generalized linear model differs from general linear model,and the interaction was composed of multiplicative interaction and additive interaction.The former is only statistical significant,but the latter has biological significance.In this paper,macros was written by using SAS 9.4 and the contrast ratio,attributable proportion due to interaction and synergy index were calculated while calculating the items of logistic and Cox regression interactions,and the confidence intervals of Wald,delta and profile likelihood were used to evaluate additive interaction for the reference in big data analysis in clinical epidemiology and in analysis of genetic multiplicative and additive interactions.

15.
Artículo en Inglés | IMSEAR | ID: sea-176339

RESUMEN

Background & objectives: Persistent infections with high-risk (HR) human papillomaviruses such as HPV 16, 18, 31, 33 and 45 have been identified as the major aetiological factor for cervical cancer. The clinical outcome of the disease is often determined by viral factors such as viral load, physical status and oncogene expression. The aim of the present study was to evaluate the impact of such factors on clinical outcome in HPV16 positive, locally advanced cervical cancer cases. Methods: One hundred and thirty two pretreatment cervical tumour biopsies were selected from patients undergoing radiotherapy alone (n=63) or concomitant chemo-radiation (n=69). All the samples were positive for HPV 16. Quantitative real time-PCR was carried out to determine viral load and oncogene expression. Physical status of the virus was determined for all the samples by the ratio of E2copies/E7copies; while in 73 cases, the status was reanalyzed by more sensitive APOT (amplification of papillomavirus oncogene transcripts) assay. Univariate analysis of recurrence free survival was carried out using Kaplan-Meier method and for multivariate analysis the Cox proportional hazard model was used. Results: The median viral load was 19.4 (IQR, 1.9- 69.3), with viral integration observed in 86 per cent cases by combination of the two methodologies. Both univariate and multivariate analyses identified viral physical status as a good predictor of clinical outcome following radiation treatment, with episomal form being associated with increased recurrence free survival. Interpretation & conclusions: The present study results showed that viral physical status might act as an important prognostic factor in cervical cancer.

16.
Chinese Journal of Applied Clinical Pediatrics ; (24): 1476-1478, 2015.
Artículo en Chino | WPRIM | ID: wpr-478998

RESUMEN

Objective To study the prognosis of gastroesophageal reflux disease ( GERD) in children, and explore the factors which impacts on the prognosis of GERD. Methods One hundred and thirteen children with GERD were enrolled on the basis of positive result of 24-hour pH-monitoring between January 2007 and November 2011. The number of patients who were followed up was 87,and the parents of children were contacted with the telephone. The prognosis was evaluated by comparing the degree of patients′symptom relief,and the cumulative symptom relief rate was calculated by Kaplan-meier product limit method. The univariate Log-rank test and the COX proportional hazardmodel multivariate analysis were applied to detect the factors impacting on the prognosis,including age,gender,the regularity of treatment,reflux index,and Boix-Ochoa standard score,with esophageal hiatal hernia or without,receiving surgical treatment or not,the diet and lifestyle improved or not,receiving anti-acid treatment or not,as well as with allergies his-tory or without. Results At last,76 out of 87 children had symptom relieved. Survival curve showed the cumulative symptom relief rate at different time points,the median cumulative symptom relief rate reached 6 months,the final relief rate was close to 90. 0%,and the continuous treatment time was 44 months. The study showed that 14. 9% (13/87 ca-ses) of children′s growth and development were affected and the life and learning in 16. 1% (14/87 cases) of children were impacted. Age (P=0. 012,Wald=6. 376) and the regularity of treatment (P=0. 000,Wald=13. 059) were the risk factors in the prognosis of GERD. Conclusions Age and the treatment regularity were the factors in the prognosis. The children aged more than 1-year old have poor prognosis compared with those less than 1-year old,and the irregular treatment is the risk factor in the prognosis.

17.
Journal of Preventive Medicine and Public Health ; : 216-224, 2015.
Artículo en Inglés | WPRIM | ID: wpr-211243

RESUMEN

OBJECTIVES: Decreased fertility and impaired health owing to early menopause are significant health issues. Smoking is a modifiable health-related behavior that influences menopausal age. We investigated the effects of smoking-associated characteristics on menopausal age in Korean women. METHODS: This study used data from the Korea National Health and Nutrition Examination Survey from 2007 to 2012. Menopausal age in relation to smoking was analyzed as a Kaplan-Meier survival curve for 11 510 women (aged 30 to 65 years). The risk of entering menopause and experiencing early menopause (before age 48) related to smoking were assessed using a Cox proportional hazards model. RESULTS: The menopausal age among smokers was 0.75 years lower than that among non-smokers (p<0.001). The results of the Cox proportional hazards model showed pre-correction and post-correction risk ratios for entering menopause related to smoking of 1.26 (95% confidence interval [CI], 1.09 to 1.46) and 1.27 (95% CI, 1.10 to 1.47), respectively, and pre-correction and post-correction risk ratios for experiencing early menopause related to smoking of 1.36 (95% CI, 1.03 to 1.80) and 1.40 (95% CI, 1.05 to 1.85), respectively. CONCLUSIONS: Smokers reached menopause earlier than non-smokers, and their risk for experiencing early menopause was higher.


Asunto(s)
Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Factores de Edad , Estudios Transversales , Demografía , Menopausia , Encuestas Nutricionales , Modelos de Riesgos Proporcionales , República de Corea , Factores de Riesgo , Fumar
18.
Artículo en Inglés | IMSEAR | ID: sea-172401

RESUMEN

Incubation period of HIV to AIDS is a vital tool that plays an important role in estimating the longevity or survivability of the HIV infected patients. However, death of AIDS patients when considered as end point becomes meaningful while finding the actual survivability of an individual. The present study is focused in analyzing the data on 343 AIDS patients who were recommended to undergo treatment in the ART centre followed up for a period of 6 years. The study included a cohesive treatment of censored observations based on lost to follow-up, deaths, recovered and alive cases till the end of study as well as uncensored observations. On the basis of diagnosed AIDS cases, the estimates of survivability under various conditions have been obtained. This paper also incorporates the trend of survivability for the reported AIDS patients with respect to age, sex, stages and mode of transmission across these 6 years. Kaplan Meier estimation method and Cox proportional hazard model were applied to determine the effect of various covariates that may be responsible for the death of the AIDS patients, survival pattern.

19.
Indian J Ophthalmol ; 2012 Jan; 60(1): 15-21
Artículo en Inglés | IMSEAR | ID: sea-138783

RESUMEN

Aim: To study the indications, risk factors, postoperative course, and long-term survival of corneal transplants done for optical purposes. Design: Retrospective case series. Materials and Methods: Data were obtained by reviewing the records of 181 patients operated at our institute (H.V. Desai Eye Hospital) between October 2005 and October 2007 for optical penetrating keratoplasty. Patients with less than one year of follow up, pediatric cases, therapeutic, tectonic, and lamellar keratoplasties were excluded. Kaplan Meier survival analysis was used to calculate median survival time of grafts and to see correlation between nine variables viz. age, gender, corneal vascularization, previous failed grafts, previous Herpes Simplex keratitis, post-perforation corneal scars, donor tissue quality, graft size, type of surgery and follow-up. These variables were also used for univariate and multivariate analysis using Cox Proportional Hazard Regression Modeling. Results: Median survival of the cohort was 27 months (95% confidence interval: 20.47-33.52). One- and two-year survival rates were 65% and 52.5%, respectively. Median survival was significantly lower in poor prognosis cases (14 months) than good prognosis cases (27 months, P = 0.0405). Graft survival was lower in vascularized corneas (18.55 months, P = 0.030) and in post-perforation corneal scars (17.96 months, P = 0.09, borderline significance). Multivariate analysis showed that the same factors were predictive of graft failure. Conclusion: Long-term survival of grafts at our center is different from centers in western world. More high-risk cases, paucity of excellent quality donor corneas, and differences in patient profile could be the contributory factors.


Asunto(s)
Enfermedades de la Córnea/patología , Enfermedades de la Córnea/fisiopatología , Enfermedades de la Córnea/cirugía , Femenino , Estudios de Seguimiento , Supervivencia de Injerto/fisiología , Humanos , Incidencia , India/epidemiología , Queratoplastia Penetrante/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Agudeza Visual
20.
Chinese Journal of Infectious Diseases ; (12): 276-281, 2011.
Artículo en Chino | WPRIM | ID: wpr-416406

RESUMEN

Objective To explore the influence factors on hepatitis B virus (HBV) relapse after nucleos(t)ide analogues (NA) withdrawal in the chronic hepatitis B (CHB) patients who met NA cessation criteria. Methods Eighty-one consecutive CHB patients were treated with NA, 38 with lamivudine (LAM), 25 with adefovir dipivoxil (ADV), 12 with entecavir (ETV), 6 with LAM +ADV. Among recruited patients, 40 were hepatitis B virus e antigen (HBeAg) positive, 41 were HBeAg negative, 67 of them were initial treatment, 14 were retreatment due to resistance to NA at baseline. The treatment was discontinued after meeting China therapeutic end-point criteria. HBV DNA, HBV serological markers, alanine aminotransferase (ALT) were measured respectively at baseline, every month before virological response, every 3 months after virological response, every month within first 6 months and every 2 months over 6 months after drugs withdrawal. Twelve probable influence factors on relapse which were sex, age, HBV family history, baseline HBV DNA,baseline HBeAg status, baseline ALT, virological response time, total duration of treatment, duration of additional treatment, the level of hepatitis B virus surface antigen (HBsAg) at cessation therapy,initial treatment or retreatment, drug category were analyzed with univariate, multivariate Cox regression modle and stratified analysis. The cumulative relapse was calculated by the Kaplan-Meier method. Results A total of 36 patients (44. 4%) relapsed within 1 year. Initial treatment or retreatment, HBV family history, virological response time, the level of HBsAg at cessation therapy were independent risk factors. The relapse rate of retreatment was higher than that of initial treatment (78.6% vs 37. 3% , χ2 = 7. 983, P = 0. 005) , those of patients with HBV family history higher than without family history (64. 5% vs 15.0%, χ2 =12. 096,P = 0.002), those of patients obtained virological response within 3 months lower than after 3 months(34. 0% vs 64. 3% , χ2 =6. 823,P=0. 009) , those of patients with HBsAg≤150 μg/L at cessation therapy lower than >150 μg/L(27. 6% vs 53. 8%, χ2=5. 199,P=0. 023). Conclusions Retreatment, HBV family history, later virological response and higher HBsAg level at cessation therapy are risk factors of relapse after NA withdrawal. Such patients should be treated with prolonged duration after meeting end-point criteria to strengthen the efficacy.

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